taxonID	type	description	language	source
111A5C1AE00DFFE0991748EFFB11ADE4.taxon	description	ethanol) from a local friend (Mr. Ang Wei Ayang in Tang & Liu, 2024). The Chinese species, Scorpiops jendeki Kovařík, 1994, has been informally misidentified as this species (Tang, 2022 c: 14). Chaerilus sp. (cf. herta sp. n.), China, Tibet Autonomous Region, Nyingchi City, Mêdog County, June 2024, 2 ♀ (Figs. 52 – 67), purchased dried specimens from goofish. com, allegedly from a recent expedition to this county, collector unknown. Chaerilus sp. (aff. chubluk), Vietnam, Đ ắk L ắk Province, Buôn Ma Thu ột City, Hòa Khánh Commune, December 2023, 2 ♀ 1 ♂ (alive), 2 juv. ♂ (now preserved in 75 % ethanol), purchased specimens from a local friend; not examined in detail. Abbreviations. Morphology: CAM, carapace anterior margin; CG, carapacial granulation; ChL / W, pedipalp chela length (ChL) to width (ChW) ratio; CPM, centro-posteromedian carina (e); DSC, pedipalp movable finger denticle subrow count (s); EDD, enlarged distal denticle; EPD, enlarged proximal denticle; FL / CaL, pedipalp femur length (FL) to carapace length (CaL) ratio; MIIC, number of carinae on metasoma II; MLMa, mediolateral major ocellus (i); PLMa, posterolateral major ocellus (i); PTC, pectinal tooth count (s); SVII, ventral surface of sternite VII; TL, total length (in mm); VADC, ventral accessory denticle (VAD) count (s) of cheliceral finger (movable / fixed). Others: AC, anonymous collector; ANOVA, analysis of variance; CC, canonical correlation; CDA, canonical discriminant analysis; CV, canonical variables; FAMD, factorial analysis of mixed data; HCA, hierarchical cluster analysis; ISS, incorrect subsequent spelling; KMCA, k-means cluster analysis; KMO, Kaiser-Meyer-Olkin measure; MAE, mean absolute error; MANOVA, multivariate ANOVA; MCA, multiple correspondence analysis; MCS, Monte Carlo simulation; MWU, Mann-Whitney U test; PCA, principal component analysis; PD, principal dimension; PERMANOVA, permutational MANOVA; RMSE, rootmean-square error; SD, standard deviation; SW, Shapiro-Wilk test; UPGMA, unweighted pair group method with arithmetic mean; UV, ultraviolet; WSR, Wilcoxon signed-rank test. Specimen Depositories. FKCP, personal collection of František Kovařík, Prague, Czech Republic (will in future be merged with the collections of the National Museum of Natural History, Prague, Czech Republic); MHBU, Museum of Hebei University, Baoding, China; MNHN, Muséum National d´Histoire Naturelle, Paris, France; MWHU, Museum of Wuhan University, Wuhan, China; NHMUK, Natural History Museum, London, UK; NZSI, National Collection, Zoological Survey of India, Kolkata, India; USTC, University of Science and Technology of China, Hefei, China; VT, personal collection of Victoria Tang, Shanghai, China (will in future be donated to NHMUK); ZMNH, Zoologie des Museums der Natur Hamburg, Hamburg, Germany (formerly known as “ Zoologisches Institut und Zoologisches Museum, Universität Hamburg, Germany ”).	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE002FFE89AF24AF4FB5BAFE9.taxon	description	1 A 10 - 4 ADF-AA 7 A- 24 C 758187 ECB	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE002FFE89AF24AF4FB5BAFE9.taxon	materials_examined	TYPE MATERIAL (Kraepelin, 1913: 144). India, Assam State, 1 ♂, 1 juv. ♀, NZSI. MATERIAL EXAMINED. None.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE002FFE89AF24AF4FB5BAFE9.taxon	diagnosis	DIAGNOSIS. TL ca. 31.5 – 41.5 mm for ♂ and 36.75 mm for ♀. General color reddish to dark brownish; legs pale brown; telson reddish brown. Two pairs of lateral ocelli and one pair of median ocelli. Carapace and tergites granular, stronger in ♀; CAM arched (or weakly concave?) in ♂, straight in ♀; sternite III – VI smooth, VII granular and tetracarinate. Metasoma I – V with carinae 10 - 8 - 8 - 8 - 7. Male telson not strongly elongated. PTC 4 – 5 in both sexes. VADC of cheliceral movable / fixed fingers 4 – 5 / 8 – 10. Pedipalp chela slender in ♂ (?), ChL / W ca. 3.25 in ♂; manus with D 1, D 3 – 5, E, and V 1, 3 present, smooth (?) to granular, I obsolete; D 3 mostly obsolete (?), indicated distally and proximally; DSC of movable finger 7 – 8 (? 9), dorsal edge of movable finger straight. CURRENT ASSESSMENT OF TAXONOMIC VALIDITY. Valid; but its synonymy with C. dibangvalleycus remains dubious.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE002FFE89AF24AF4FB5BAFE9.taxon	discussion	REMARKS. Kraepelin (1913: 144 – 145) roughly characterized C. assamensis based on an adult male (31.5 mm, PTC 5 / 5) and a juvenile female (22 mm, PTC 4 / 4) from Assam, India. He noted that this species differs from all other congeners of the time by a distinctly arched (vs. straight) CAM in the male, which is flatter in the female (“ … einen stärker gekrümmten Kreisbogen bildende Rundung des Stirnrandes … ”; op. cit.: fig. 3 a – b). All carinae on the pedipalp manus were described as developed and almost smooth, except for the “ secondary inner keel ” (= D 5; op. cit.: fig. 2) being somewhat granular (“ … Handkiele alle entwickelt und alle fast glatt, nur der sekundäre Innenrandkiel etwas zackig körnig … ”). This species has never been revised based on any materials since then. Another character later emphasized by Kovařík (2000: 42) was the presence of 7 – 8 subrows of denticles on the pedipalp chela movable finger (Kraepelin, 1913: “ … Schrägreihen des beweglichen Scherenfingers (bezw. der äusseren Seitenkörnchen mit Einschluss des Endkörnchens) nur 7 – 8 … ”, “ … Beweglicher Finger mit sieben Schrägreihen … ”), a count then observed only in C. tryznai from China (now known to occur in several other Chaerilus species). Bastawade (2006: 451) described C. dibangvalleycus based on a number of adult specimens and two juveniles. Although the description was more detailed, several issues hinder a clear understanding of this species. Most importantly, he did not clarify the sex of the specimen illustrated. While the pectines showed 3 teeth (op. cit.: fig. 6), rendering it more likely a female, the presence of a pair of genital papillae (cited in the description) suggests it was a male. However, the author calculated 4 teeth for males and 5 for females. Moreover, he initially mentioned the presence of 4 and 8 – 9 ventral accessory denticles on cheliceral movable and fixed fingers (op. cit.: 451), but then shifted these counts to 5 and 10 in his interspecific comparison (op. cit.: 454). The illustration (op. cit.: fig. 4) showed 9 accessory denticles on the fixed cheliceral finger. Kovařík (in Kovařík & Ojanguren-Affilastro, 2013: 133) synonymized C. dibangvalleycus with C. assamensis based primarily on geographic proximity and identical DSC, albeit examining no specimens. The current investigation further discovered that the descriptions of both species documented sexual dimorphism in the tergal granulation development, where it is weaker in males. Kovařík considered the carapace illustration in Bastawade (2006: 452, fig. 1) pertained to the female paratype, yet the original author did not explicate the sex in either description or figure caption. If one assumes that all depictions were of the male holotype (as that of the pectines), then the male C. dibangvalleycus clearly shows a weakly concave CAM. Another discrepancy between the two species lies in the metasomal carinae. Kraepelin (1913: 144) described the male C. assamensis as lacking inframedian (= median lateral) carinae (“ untere Mediankiele ”) on metasoma I – II. On the contrary, Bastawade (2006: 451) claimed that in C. dibangvalleycus, all carinae on metasoma I are well-developed, but the “ laterals ” on metasoma II – IV are not, suggesting a carina formula of 10 - 8 - 8 - 8 for metasoma I – VI. In addition, Kraepelin (1913: 144) briefly characterized the sternites of C. assamensis as matt and agranular (“ … Bauchplatten matt, ungekrönt … ”), contradicting the granular and carinate sternite VII described for C. dibangvalleycus, though it is unclear if Kraepelin’s qualification applies to all sternites. There was no indication from Kraepelin of a reduction in D 3 on the chela carinae, while the opposite appears to be the case in C. dibangvalleycus (Bastawade, 2006: fig. 14). Kraepelin also did not provide enough metrics, but noted that the pedipalp finger was shorter than the manus in both sexes (“ … F [inger].: H [inter] hand beim ♂ = 3,5: 5, beim ♀ 2,5: 3 … ”) and a length to width ratio of manus for both sexes (“ … Verhältnis von Länge der Hinterhand zur Handbreite beim ♂ = 5: 3, beim ♀ = 3: 2 … ”). He described the chela as “ rather narrow ” (“ … Hand ziemlich schmal … ”) without specifying any difference between sexes, which could suggest either a weak sexual dimorphism (as also indicated by the manus ratio) or an ontogenetic variation (i. e., juvenile female had narrower manus than its adult counterpart). Bastawade, on the other hand, noted that male C. dibangvalleycus are more slender than females. This further suggest that his original figures were more likely depicted for the male holotype, where a narrow chela was illustrated. A crude measurement based on his figure 14 yields a ChL / W of 3.25. In any case, the taxonomic status of both species is currently unclear. Given the morphological incongruence in some aspects between the two species, C. dibangvalleycus may in fact be a valid species. However, whether synonymous or not, the decision largely depends on the reliability of the characters discussed (i. e., whether they are intraspecifically stable in the two species): CAM, pedipalp and metasomal carinae, sternite, and ChL / W. The earliest mentioning of C. assamensis as a member of the scorpiofauna of China appears to be in Di et al. (2009: 132 – 133), who cited Kraepelin (1913: 144) and Kovařík (2000: 42, tab. 2) in the bibliography under this species. This is baffling as neither work considered this species to be distributed in China or Arunachal Pradesh, since only two specimens of this species have been known for the whole time. Chaerilus dibangvalleycus was also included in their Chinese checklist, which was not synonymized with C. assamensis at that time. It is likely that the authors misread the table 2 in Kovařík (op. cit.: 72). This error perpetuated until Di et al. (2013: 52) and Di et al. (2014: 5) corrected it. Di et al. (2013: 55) considered the type locality of C. dibangvalleycus to be located in Mêdog County. According to the 2023 version administrative division map of Nyingchi City provided by the Department of Natural Resources of the Xizang Autonomous Region, the Dibang Valley District covers both Mêdog and Zayü counties. Approximated coordinates based on Bastawade (2006: map 1) place the type locality within Zayü (Fig. 1), though rather near the border with Mêdog. It, however, would not be surprising that this species occurs in both counties. On iNaturalist, one observation record (obs. ID = 219229842) from Mêdog (28 ° 50 ' 12.0 '' N 95 ° 52 ' 25.9 '' E) featured an apparently young adult male Chaerilus species, close to the type locality of C. dibangvalleycus (ca. 8 km). The specimen matches Bastawade’s description for the coloration, as well as a narrow chela with obsolete D 3. A weakly concave CAM can also be observed from the fourth photograph. To secure the record, photographs are reproduced with permission in Figs. 2 – 4. Another observation (obs. ID = 258985048) was recently uploaded for the same record (same date and coordinate). Di et al. (2013: 57) also noted that “ … Both sexes of C. conchiformus, C. dibangvalleycus and C. tryznai have anterior margin truncated, but only females of C. mainlingensis have same anterior margin of carapace as C. dibangvalleycus … ”, which is bewildering. Only one sex (presumably male) of C. dibangvalleycus has been illustrated, which shows a weakly concave CAM, not “ truncated ” (= straight). Chaerilus mainlingensis is known only from females, and the original authors (with the senior author being Z. - Y. Di, who made the above statement) also described its CAM as “ weakly concave ” (Di & Zhu, 2009: 98). Therefore, while their second sentence holds true, it contradicts with the first where the CAM was regarded straight for C. dibangvalleycus. In their dichotomous keys, Yin et al. (2015: 49) characterized this species as “ … carapace with anterior margin straight with a median notch … ”, an eccentric description. A notch refers to an abrupt concavity seen in, for example, all Scorpiops species, which is not observable in Bastawade’s illustration. A straight margin with a median notch suggests the concavity is not gradual, but prominent. However, the original depiction shows a smooth inward curvature.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE002FFE89AF24AF4FB5BAFE9.taxon	distribution	DISTRIBUTION. Known only from the type locality; Zayü County (“ Mayodia ”), in Nyingchi City.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE005FFEB991C4E15FCEBADE9.taxon	description	(Figures 12 – 19; Tables 1 – 2) http: // zoobank. org / urn: lsid: zoobank. org: act: 5726 EDCE- 209 E- 42 B 7 - B 2 F 8 - 4075 F 5 D 3 F 8 D 1	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE005FFEB991C4E15FCEBADE9.taxon	materials_examined	TYPE MATERIAL (Zhu et al., 2008: 39) [lost]. China, Tibet Autonomous Region, Nyingchi City, Bayi District, Bayi Town, 29 ° 41 ' N 94 ° 21 ' E (type locality), 1 ♀, MHBU; Nyingchi City, Bayi District, hill behind the Xizang Agricultural and Animal Husbandry University (specified in Di, 2009: 99), 1 juv. ♀; Nyingchi City, Bayi District, Baishuwang Town, 29 ° 34 ' N 94 ° 30 ' E, 6 ♀, MHBU; Nyingchi City, Mainling City, Zhaxiraodeng Township (“ Pai Town ”?), 29 ° 12 ' N 94 ° 06 ' E, 1 ♂, MHBU. OTHER MATERIAL. China, Tibet Autonomous Region, Nyingchi City, Bayi District, Bayi Town, 1 juv., MHBU (Qi et al., 2005: 34); Nyingchi City, Bayi District, Bayi Town, 29 ° 41 ' N 94 ° 21 ' E (= type locality), 1 ♂ 3 ♀, 1 juv. (Di, 2009: 99); Nyingchi City, Bayi District, Bayi Town, hillside north of Xizang Agricultural and Animal Husbandry University, 29 ° 39 ' 50.6 '' N 94 ° 20 ' 35.4 '' E (approximated), 2 ♀, 7 juvs (Di, 2009: 99); Nyingchi City, Mainling City, 1 juv. (Di, 2009: 99). One ♀ reported in Yin et al. (2015: 46). MATERIAL EXAMINED (VT). China, Tibet Autonomous Region, Nyingchi City, Mainling City, Milin Town, 29 ° 12 ' 51.6 '' N 94 ° 12 ' 46.2 '' E, 2936 m a. s. l., 21 st November 2022, 1 ♂, leg. Yiyang Xu (Figs. 12 – 19).	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE005FFEB991C4E15FCEBADE9.taxon	diagnosis	DIAGNOSIS. TL ca. 43.47 mm for ♂ and 32 – 41.04 mm for ♀. General color reddish brown to dark brown. Two pairs of lateral ocelli and one pair of median ocelli. Carapace and tergites granular, stronger in ♀; CAM straight; sternite III – VI smooth, VII subgranular and tetracarinate. Metasoma I – V with carinae 10 - 10 - 8 - 8 - 7. Male telson not strongly elongated. PTC 5 in ♂ and 3 – 4 in ♀. VADC of cheliceral movable / fixed fingers 5 – 6 / 5 – 6 (8?). Pedipalp chela not strongly sexually dimorphic, rounded in both sexes, ChL / W ca. 1.77 in ♂ and 1.6 – 1.9 in ♀; manus with D 1, D 3 – 5, and V 1, 3 present and granular, E and I obsolete; DSC of movable finger 7 – 8, dorsal edge of movable finger straight. CURRENT ASSESSMENT OF TAXONOMIC VALIDITY. Valid, but pending the designation of a neotype.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE005FFEB991C4E15FCEBADE9.taxon	discussion	REMARKS. Qi et al. (2005: 34 – 38) misidentified 1 adult female and 2 juvenile Chaerilus from Bayi Town (in Bayi District) as C. pictus. The same adult female (17 th August 2002) was later used as the holotype for describing C. conchiformus (Zhu et al., 2008: 38 – 39), and one of the juveniles (6 th August 2003) was listed as a female paratype, while the other juvenile (sex not specified; 2 nd August 2002) was neglected from the type series. Qi et al. (2005: 34) used the name “ Bayizhen town ” for the origin of the adult female, which was changed to “ Bayi Town ” in Zhu et al. (2008: 39), in accordance with the two original juveniles. The Pinyin “ zhèn ” (Dz) is semantically synonymous with “ town ” in English, hence this name constitutes a tautological toponym. Zhu et al. (op. cit.) further listed 6 female paratypes (July 2006) from Baishuwang (“ Cypress King ”) Town (in Bayi District) and 1 male paratype (30 th July 2006) from “ Pai Town ” (in Mainling City). However, the coordinates they provided for “ Pai Town ” traces to Zhaxiraodeng Township (in Mainling City) according to Google Maps, located ca. 80 km southwest of Pai Town (29 ° 30 ' 16.0 '' N 94 ° 51 ' 03.9 '' E). Later, in Di’s (2009: 99) dissertation, a total of 1 male, 6 females, and 10 juveniles were reported from Bayi Town; also included was a juvenile (7 th August 2003) from Mainling City. Among the 17 specimens from Bayi, based on the collection date, one was the holotype female. The single male, 1 juvenile, and 3 females were collected by Z. - Y. Di on 12 th July 2008, but they all share exactly the same coordinates with the holotype female (29 ° 41 ' N 94 ° 21 ' E). The name of their locality was given as “ Dabaishu Scenic Spot ” (k 柏树Kã区), which is most likely what is now called “ Baishuwang Scenic Spot ” (柏树王ã区). In the remaining 11 specimens, the neglected juvenile (2 nd August 2002) reappeared. Finally, 2 females and 8 juveniles were collected near Xizang Agricultural and Animal Husbandry University by different collectors on two different dates. However, one of these juveniles appears to be the paratype female (6 th August 2003) chosen from Qi et al. (2005) by Zhu et al. (2008), given the identical date and collector. The other 9 new specimens were collected by Zhu et al. on 2 nd August 2006, with coordinates approximated above (Fig. 1). Additional records are cited from iNaturalist as follows: Nyingchi City, Bayi District, Xianjin Town, 29 ° 47 ' 29.0 '' N 94 ° 22 ' 20.9 '' E (iNaturalist obs. ID = 196900795), 29 ° 39 ' 47.7 '' N 94 ° 20 ' 09.4 '' E (iNaturalist obs. ID = 248548420); Nyingchi City, Mainling City, Milin Town, 29 ° 12 ' 50.7 '' N 94 ° 12 ' 31.0 '' E (iNaturalist obs. ID = 142538526; same collector of the adult male examined herein). While the materials reported for C. conchiformus are puzzling, this species is fairly distinctive within all Chinese congeners due to its strongly dilated and somewhat flattened pedipalp chelae in both sexes, dorsally adorned with conspicuous and subgranular carinae. The pedipalp feature alone renders it unique and easily recognizable. Nevertheless, confusions persist when comparing descriptions by Qi et al. (2005: 34) and Zhu et al. (2008: 39 – 40). All sternites were described as smooth in the earlier work, but Zhu et al. (2008) noticed the subgranular and tetracarinate sternite VII. Qi et al. (2005) documented 10 carinae on metasoma I – VI, with a pair of “ lateral ” (likely “ median lateral ”) carinae gradually fading out on segment II – IV. On the other hand, Zhu et al. (2008) described the metasoma carina formula as 10 - 10 - 8 - 8 for segment I – VI, mentioning the distal reduction of “ lateral carinae ” on segment II, yet without explaining the condition on III – IV. Qi et al. (2005) enumerated a VADC of 8 for both movable and fixed cheliceral fingers, a count decreased to 6 in Zhu et al. (2008), without providing any explanation. It is worth reiterating that both works, which M. - S. Zhu coauthored, were based on the very same female specimen. Perplexity extends to the measurement of this same specimen — all values are virtually different. Zhu et al. (2008) claimed that TL in C. conchiformus is 32 – 41.04 mm in females and 43.47 mm in male. They wrote in their table caption that the metrics pertained to the holotype female (also noted within the table), yet it is apparent that those values correspond to the paratype male. The TL was given as 43.47 mm (≠ 39.89 mm in Qi et al.) and the PTC was given as 5 / 5, contradicting with their female description (3 / 4, op. cit.: 39) but instead matching that of the male (op. cit.: 42). Amusingly, in Di’s (2009: 151) dissertation, his table 5 listed the male paratype as the holotype, while the largest female (41 mm) was degraded to the paratype. In this case, FL / CaL is less than 1 for male C. conchiformus (4.5 / 5.3), and so is the female (3.6 / 4.95). In the dichotomous keys provided by Di et al. (2009: 132), the lower bound of ChL / W of C. conchiformus was declined to 1.6, a value recycled in Di et al. (2013: 88) and Di et al. (2014: 14). This appears to be derived from the “ paratype female ” measured in Di’s dissertation (7.7 / 4.8). In the original description, both holotype female and the single male were given a ChL / W of 1.8; calculation from the table 1 in Zhu et al. (2008) yields a ChL / W of 1.77. This suggests that either the value attributed to the female was erroneous, or this female was not the “ paratype female ” studied by Di (indeed, 41 ≠ 39.89, unless one admits the mensurational inconsistency). These confusions were long overlooked, as the data were all concealed in their Chinese dissertations, which had never been published. In Yin et al. (2015: 46), measurement based on a new female specimen (deposited in USTC, without collection details) increased the upper bound to 1.9 for ChL / W of C. conchiformus. The authors provided a range of 1.6 – 1.9 for female C. conchiformus in their dichotomous keys (op. cit.: 49), yet listing the value as 1.8 – 1.9 in their table 3 (op. cit.: 48), while considering the ChL / W of males unknown. Yin et al. (op. cit.) recorded their new female with a DSC of 7 in table 2, which was then increased to 8 in table 3. This is because they used two different meristics — RN (“ number of granule rows on the movable finger of the pedipalp ”) in table 2, and RF (“ row number of denticles on the fixed and movable fingers of the chelae ”) in table 3 (but why adopting both “ granule ” and “ denticle ”?) — since the target finger considered differed. Clearly, RF represents a larger set ({fixed DSC, movable DSC}) than RN ({movable DSC}), yet the authors entirely ignored their count for the movable finger.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE005FFEB991C4E15FCEBADE9.taxon	distribution	DISTRIBUTION. Bayi District and Mainling City, in Nyingchi City.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE019FFF59AE248F3FE80AEC9.taxon	description	03 B 5 - 4 D 11 - 9167 - 88 BD 35 CE 1 BA 3	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE019FFF59AE248F3FE80AEC9.taxon	description	Di & Zhu (2009) was published on 13 th December, so “ C. mainling ” is not an ISS.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE019FFF59AE248F3FE80AEC9.taxon	materials_examined	TYPE MATERIAL (Di & Zhu, 2009: 97) [lost]. China, Tibet Autonomous Region, Nyingchi City, Mainling City, Milin Town, Gongbuwang Manor, 29 ° 15 ' 30.0 '' N 94 ° 17 ' 54.3 '' E (approximated), 2 ♀, MHBU. MATERIAL EXAMINED. None.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE019FFF59AE248F3FE80AEC9.taxon	diagnosis	DIAGNOSIS. TL ca. 40.36 – 40.72 mm for ♀; ♂ unknown. General color reddish brown to blackish brown. Two pairs of lateral ocelli and one pair of median ocelli. Carapace and tergites granular; CAM weakly concave; sternite III – VI smooth, VII subgranular and tetracarinate. Metasoma I – V with carinae 10 - 8 - 8 - 8 - 7. PTC 3 – 4 in ♀. VADC of cheliceral movable / fixed fingers 7 – 8 / 6. Pedipalp chela ChL / W ca. 2.4 – 2.75 in ♀; manus with D 1, D 4 – 5, and V 1, 3 present and granular, E and I obsolete; D 3 highly obsolete as an unridged dark stripe; DSC of movable finger 7, dorsal edge of movable finger straight. CURRENT ASSESSMENT OF TAXONOMIC VALIDITY. Valid, but pending the designation of a neotype.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE019FFF59AE248F3FE80AEC9.taxon	discussion	REMARKS. The description of this species was based on only two adult females, which remain the sole specimens known to date. Consequently, the available information is largely confined to the original description, and subsequent publications have been predominantly misleading. However, confusions nonetheless present in the original paper itself. Di & Zhu (2009: 98) described the chela of C. mainlingensis as “ … dorsal internal [= D 5], digital [= D 1], dorsal external, ventral internal [= V 3], ventral external [= V 1] carinae with smooth granular, external secondary [= E], external and interomedian [= I] carinae obsolete or vestigial … ”. In a different section on the same page, the authors stated that “ … dorsal secondary carinae [= D 3] of the chela obsolete as a black stripes without ridges … ”, suggesting that the correct description should likely read: “ dorsal secondary [= D 3], external secondary [= E] and interomedian [= I] carinae obsolete or vestigial ”. This leaves their “ dorsal external ” carina as “ dorsal marginal ” carina (= D 4). In contrast, Kovařík & Ojanguren-Affilastro (2013: 138) diagnosed this species with “ 8 granulated carinae ”, and reduced its PTC to 3 (3 – 4 in Di & Zhu (2009: 98 )). In their dichotomous keys, Di et al. (2013: 88) differentiated this species from C. dibangvalleycus by one of the two characters (the other being pedipalp femur longer than carapace in C. mainlingensis, and the opposite in C. dibangvalleycus) as follows (recycled by Di et al. (2014: 14) and Yin et al. (2015: 49 )): “ … 8 – 9 minute teeth on inner ventral margins of movable and immovable fingers respectively … C. dibangvalleycus ” “ … 7 – 8 minute teeth on inner ventral margins of movable and immovable fingers respectively … C. mainlingensis ” They used “ respectively ” to refer to the movable and fixed fingers while providing only one range for both, which is puzzling. At first glance, this description seems to pertain to the chelicerae, as the terms “ minute teeth ” and “ inner ventral margins ” are typically used to describe cheliceral dentition (VAD; pedipalp movable fingers do not have dentate inner ventral margins). However, they cited Bastawade (2006: fig. 5) and Di & Zhu (2009: fig. 11), both depicting the movable finger of pedipalp chela. This is rather baffling as Bastawade did not provide the DSC of fixed pedipalp finger. In Bastawade (2006: 451, right column), the author merely mentioned that “ … Pedipalp … immovable finger … provided bellow [below] with double row of minute dentition; movable finger … provided with double row of minute dentition … ”. On page 454 (op. cit., left column), the author provided a DSC of 7 – 8 for the pedipalp movable finger of C. dibangvalleycus. In Di & Zhu (2009: 98, left column), the authors stated “ … dentate margins of fixed and movable fingers of pedipalp chela with seven rows of granules … ” for C. mainlingensis. Neither datum accords with the keys originally provided by Di et al. (2013). However, if one attempts to locate those values in the respective papers, it can be found that in Bastawade (2006: 451, left column), the author stated “ … Chelicera … four and eigth [eight] to nine minute teeth on inner ventral margins of movable and immovable finger s respectively … ” (though he later shifted these counts to 5 and 10 in his interspecific comparison; op. cit.: 454), and in Di & Zhu (2009: 98), the authors stated “ … Chelicerae … ventral inner edges of movable finger with six medium-size teeth and one or two obsolete small teeth … ” (i. e., 7 – 8 VAD for cheliceral movable finger). Additionally, their figure 4 showed six VAD for the fixed cheliceral finger of C. mainlingensis. If Di et al. (2013) in fact referred to those values, they would essentially be comparing the VADC of fixed cheliceral finger of C. dibangvalleycus against that of the movable cheliceral finger of C. mainlingensis, which is inscrutable, as the senior author of that paper was the same author described C. mainlingensis. To clarify, the correct meristics for the two species are as follows (movable / fixed): (1) C. dibangvalleycus: cheliceral finger, 4 – 5 / 8 – 10, pedipalp chelal finger, 7 – 8 /?; (2) C. mainlingensis: cheliceral finger, 7 – 8 / 6, pedipalp chelal finger, 7 / 7. Despite this, C. mainlingensis itself is well distinguished according to the original data alone. The original authors compared it with C. insignis, C. pictus, C. truncatus, and C. tryznai based on mostly valid characters, particularly the DSC, which effectively differs it from C. insignis, C. pictus, and C. truncatus. Both C. insignis and C. truncatus are also geographically distant from the Tibetan region where C. mainlingensis occurs. The absence of D 3 and carinate sternite VII corroborates its distinctions from the geographically closest C. tryznai within this set of congeners. The diagnostic table summarized herein highlights these two characters as key differentiators between the two species. Within Tibetan Chaerilus, absence of D 3 is so far observed in C. dibangvalleycus, C. mainlingensis, and C. tricostatus. Based on the original data, C. tricostatus can be easily separated from C. mainlingensis by a higher DSC alone, while C. dibangvalleycus is supposedly distinguished by its higher VADC on both cheliceral fingers and slightly higher female PTC. However, it is also worth mentioning that the denticle subrows of movable finger illustrated for C. mainlingensis might be either abnormal (cf. Figs. 128 – 129) or inaccurate, as no clear imbrication could be discerned between most adjacent subrows, and several subrows appeared atypically elongated. If DSC turns out to be an erroneous diagnostic, the validity of C. mainlingensis might still be defended by its slightly lower female PTC (no pectinal anomaly was observed in the original illustration). Although the current investigation revealed that C. conchiformus is the geographically closest species (Fig. 1), the two species can be readily differed by the pedipalp chela alone. Nevertheless, since no photograph was provided for this species, further investigations are warranted to definitively confirm its validity, particularly against C. dibangvalleycus.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE019FFF59AE248F3FE80AEC9.taxon	distribution	DISTRIBUTION. Known only from the type locality; Gongbuwang Manor of Milin Town, Mainling City, in Nyingchi City.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE018FFF59ADD4CF5FA4DA848.taxon	description	5 DFB- 437 A- 8 C 64 - ACF 469 E 52 E 22	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE018FFF59ADD4CF5FA4DA848.taxon	description	Chaerilus pictus: misidentification; see C. conchiformus.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE018FFF59ADD4CF5FA4DA848.taxon	materials_examined	TYPE MATERIAL (Pocock, 1890: 252). Bangladesh, Sylhet	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE01DFFF09AA14EA9FA4DACC2.taxon	description	86 FB- 4 E 16 - 8487 - 047 B 100 BF 9 DC	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE01DFFF09AA14EA9FA4DACC2.taxon	materials_examined	TYPE MATERIAL (Yin et al., 2015: 43). China, Tibet Autonomous	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE010FFFE9ABB48F3FA38AB89.taxon	description	1 B 6 D- 4 BFE-A 2 E 3 - 9 A 2 CA 9789 B 39	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE010FFFE9ABB48F3FA38AB89.taxon	materials_examined	TYPE MATERIAL (Qi et al., 2005: 30) [lost]. China, Tibet Autonomous Region, Nyingchi City, Mêdog County, Drepung Township (?), 29 ° 02 ' N 95 ° 03 ' E (type locality), 1 ♀, MHBU; Nyingchi City, Mêdog County (incorrectly given as “ Bomê County ”), 29 ° 08 ' N 95 ° 07 ' E (Drepung Township?), 2 ♀, MHBU & MNHN; Nyingchi City, Mêdog County, 1 ♀, MHBU. OTHER MATERIAL. China, Tibet Autonomous Region, same locality as holotype, 1 juv. ♀ paratype? (Yang, 2008: 48); Nyingchi City, Bayi District (incorrectly given as “ Bayi Town to Bomê County ”), Sejila Mountain (“ Mt. Sela ”), 29 ° 37 ' 38.3 '' N 94 ° 39 ' 28.4 '' E (approximated), 1 ♀, MHBU (Zhu et al., 2008: 44; Di, 2009: 105); Nyingchi City, Bayi District, Dongjiu Village, 29 ° 49 ' 46.6 '' N 94 ° 44 ' 35.6 '' E (approximated), 2 juv. ♀, MHBU (Zhu et al., 2008: 44); Nyingchi City, Mainling City, 1 juv. (♀?; Di, 2009: 105). MATERIAL EXAMINED. None.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE010FFFE9ABB48F3FA38AB89.taxon	diagnosis	DIAGNOSIS. TL ca. 35.3 – 51.66 mm for ♀; ♂ unknown. General color dark brown, variegated; chelal manus and telson reddish brown; legs pale brown (MNHN-RS-RS 8623). Two pairs of lateral ocelli and one pair of median ocelli. Carapace and tergites smooth or granular (MNHN-RS-RS 8623); CAM weakly concave to straight; sternite III – VII smooth, VII tetracarinate. Metasoma I – V with carinae 10 - 10 - 10 - 8 - 7. PTC 3 (MNHN-RS-RS 8623) or 5 in ♀. VADC of cheliceral movable / fixed fingers 6 – 8 / 7. Pedipalp chela ChL / W ca. 2.2 in ♀; manus with D 1, D 3 (?) – 5, and V 1, 3 present and granular, E and I obsolete; DSC of movable finger 11, dorsal edge of movable finger straight. CURRENT ASSESSMENT OF TAXONOMIC VALIDITY. Dubious and pending the designation of a neotype; the status of paratype RS 8623 is indeterminate (the specimen on which the minimum TL of 35.3 mm was based was not explained in their description, but it could possibly be this paratype). See also discussions under ‘ 7. Taxonomic conclusion’.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE010FFFE9ABB48F3FA38AB89.taxon	discussion	REMARKS. This species was the second Chaerilus described from China, by Qi et al. (2005). The type series included 4 adult females from Mêdog County, with the type locality allegedly situated in Drepung Township. Qi et al. (op. cit. 30) incorrectly attributed one paratype locality to Bomê County, an error eventually repeated for eight years by Zhu et al. (2008: 44), Di et al. (2009: 133), and Di et al. (2013: 56). It is noteworthy that the Drepung Township (ca. 29 ° 14 ' 15.9 '' N 95 ° 10 ' 33.7 '' E) is much closer (ca. 13 km) to the coordinates they provided for this locality than to the type locality (ca. 26 km), which enters Arunachal Pradesh. In his dissertation, Yang (2008: 48) included an additional juvenile female (regarded as a paratype) allegedly collected alongside the holotype, and modified the type locality coordinates to “ N 29.11 E 95.10 ”, which do not even align with the original ones in decimal form (29.03, 95.05). If these new coordinates are in decimal form, they are now closer to Drepung Township (ca. 16 km); if in DMS form (29 ° 11 ' N 95 ° 10 ' E), the distance would be even smaller (ca. 6 km). He also added another adult female collected by M. - S. Zhu from “ Mt. Sejila ” (ϐψϋ 山), which seems to be located in Bayi District (originally given as “ Bayi Town to Bomê County ”). These changes were later adopted by Di (2009: 105) in his dissertation, who documented a new juvenile collected by himself from an unspecified locality in Mainling County. In their redescription of this species, the record from Mt. Sejila was changed into “ Bomi County, Mt. Sela ” (Zhu et al., 2008: 44), and two additional female juveniles were reported from Dongjiu Village (Bayi District). All specimens, except for the female “ paratype ” juvenile (Yang, 2008: 48), and one juvenile from Mainling (Di, 2009: 105), were finally listed in Di et al. (2013: 56). Problems with this species extend to inconsistencies in its morphological characterization. Qi et al. (2005: 30) described this species based on the female holotype (incorrectly referred to as “ male holotype ”) and provided a VADC of 6 for the cheliceral movable finger. Zhu et al. (2008: 44, 47) redescribed this species based on the same specimen but changed the count to 8 again without any explanation, adding a new VADC (7) for the fixed finger. Measurements for the holotype female also differed between the two works; for instance, TL was measured as 48.93 in Qi et al. (2005: 30) but as 51.66 in Zhu et al. (2008: tab. 1). Especially intriguing is their measurement for ChW, whereas Qi et al. (2005: 34) recorded 4.21 mm, Zhu et al. (2008: tab. 1) increased it to 5.22, a substantial difference. This is entirely understandable, yet it simultaneously reinforces my concern regarding the measurement accuracy (reproducibility) in scorpion taxonomy. However, the authors did not give any clarification for their data incongruence. In addition, both Qi et al. (2005: 30, 33) and Zhu et al. (2008: 46 – 47) recorded and illustrated a pair of pectines each with 5 teeth in the female holotype and suggested no intraspecific variation, but the paratype female (MNHN-RS-RS 8623) shows only 3 teeth on either pectine. More recently, Yin et al. (2015: tab. 3) characterized the CAM of this species as “ straight ”, contradicting with Zhu et al. (2008: 44, “ weakly concave ”). In the paratype female (RS 8623), however, the CAM is very weakly undulate and asymmetrical. The most prominent discrepancy lies in the qualitative description of tergal granulation, signifying yet another “ taxonomic Rashomon effect ” — a term coined herein, referring to the phenomenon where different subjective interpretations are derived from the morphology of the same specimen and hence its taxonomic position. For the same specimen, Qi et al. (2005: 30) stated “ … Carapace … with densely coarse granules … Tergites are coarsely granular … ”, while Zhu et al. (2008: 38, 44, 47) claimed, respectively, “ … carapace almost smooth on lateral and posterior margins … ”, “ … Carapace is almost smooth on lateral and posterior margins … Mesosomal tergites smooth … ”, and “ … Carapace covered with sparse granules of unequal size on inner portions of lateral carinae almost smooth on lateral and posterior margins … Mesosomal tergites not lustrous and almost smooth … ” The stark contradiction in their descriptions, particularly in adjective terms, can be considered diagnostic for different species in some cases. This highlights the subjectivity in qualitative descriptions and underscores the importance of including detailed photographs in species descriptions. After scrutinizing the photograph of the paratype female (RS 8623) deposited in MNHN, I corroborate the presence of a large, triangular, relatively smooth area on the lateral sides near the posterior surface on carapace. Current examination reveals that reduction of granulation on the lateral surfaces of carapace is a common condition in Tibetan Chaerilus species. However, only C. tessellatus has been described as such in previous papers (Table 1), where this character was applied diagnostically. On the other hand, the same photograph shows dense granulation on nearly all tergite surfaces, as indicated by the reflections of those granules. Nonetheless, this could simply imply different conditions present in the holotype and paratype females. Subsequently, Di et al. (2009: 133) characterized this species with even more generalized phrasing in their dichotomous keys as follows (recycled in Di et al. (2013: 88), Di et al. (2014: 14), and Yin et al. (2015: 50 )): “ … Carapace, tergites nearly smooth in adults … ” Similarly, both Qi et al. (2005: 30) and Zhu et al. (2008: 47) implied that sternite VII was “ smooth ” in this species (at least the holotype female, since they provided no comments on other materials): “ … Sternites are smooth; segment VII has two pairs of dentated carinae … ”, “ … Sternites smooth; sternite VII with two pairs of dentated carinae weakly developed … ” However, evident granules can be observed on the lateral sides and posterior region of sternite VII in the paratype female (RS 8623). These confusions raise doubts about the accuracy of those authors’ qualitative description. Despite the above complications, the presence of 11 subrows of denticles on its pedipalp movable finger presumably secures its validity (Table 1), a count shared only with C. tricostatus (10 – 12), from which C. tessellatus can be, theoretically, most reliably distinguished by the presence of D 3 (Yin et al., 2015: tab. 3; but see ‘ 7. Taxonomic conclusion’). Its distinction from C. pictus, a species recorded with a similar DSC (13 – 14), is discussed above.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE010FFFE9ABB48F3FA38AB89.taxon	distribution	DISTRIBUTION. Drepung Township (“ Beibengxiang ”) of Mêdog County, Dongjiu Village (“ Dongjiucun ”) and Sejila Mountain of Bayi District, and Mainling City, in Nyingchi City. However, most localities are dubious, as no descriptions were provided for specimens originating from those regions.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE013FFFB998F49B5FE1AA8A9.taxon	description	(Figures 36 – 43, 212; Tables 1 – 2) http: // zoobank. org / urn: lsid: zoobank. org: act: 4 D 9 B 559 C- 2 C 6 C- 44 C 4 - AF 26 - 6227 F 8635 F 21	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE013FFFB998F49B5FE1AA8A9.taxon	materials_examined	TYPE MATERIAL (Pocock, 1899: 267). India, Assam State, Tinsukia District, Sadiya Town (? in Khasi Hills), 2 ♂, NHMUK. OTHER MATERIAL. China, Tibet Autonomous Region, Nyingchi City, Mêdog County, Abor Hills, 28 ° 07 ' 58.2 '' N 95 ° 07 ' 26.7 '' E (approximated), 1 ♀, ZMNH (Henderson, 1913: 131); Nyingchi City, Mêdog County, 29 ° 20 ' N 95 ° 20 ' E, 3 ♀, 4 juv. ♀, MWUH (Di et al., 2009: 133). MATERIAL EXAMINED (VT). China, Tibet Autonomous Region, Nyingchi City, Mêdog County, June 2024, 1 ♀, purchased dried specimen, collector unknown (Figs. 36 – 43, 212).	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE013FFFB998F49B5FE1AA8A9.taxon	diagnosis	DIAGNOSIS. TL ca. 48 – 52.1 mm for ♂ and 55.3 – 59.2 mm for ♀. General color dark blackish brown. Two pairs of lateral ocelli and one pair of median ocelli. Carapace and tergites granular, denser in females; CAM straight; sternite III – VI smooth, VII smooth to granular and tetracarinate. Metasoma I – V with carinae 10 - 8 - 8 - 8 - 7. Male telson not strongly elongated. PTC 5 – 6 in ♂ and 4 – 6 in ♀. VADC of cheliceral movable / fixed fingers 7 – 11 / 7 – 8. Pedipalp chela notably slender in ♂, ChL / W ca. 3.71 in ♂ and 2.21 – 2.43 in ♀; manus with D 1, D 4 – 5, and V 1, 3 present and granular, E and I obsolete; D 3 highly obsolete an unridged dark stripe, indicated distally and proximally; DSC of movable finger 10 – 12, dorsal edge of movable finger straight. CURRENT ASSESSMENT OF TAXONOMIC VALIDITY. Valid.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE013FFFB998F49B5FE1AA8A9.taxon	discussion	REMARKS. The Chinese population of C. tricostatus was first reported by Henderson (1913: 131) as an adult female from “ Upper Rotung ” in “ Abor country ” (a record cited by Kovařík (2000: 62 )), which refers to the Abor Hills north of Rottung Village in Siang District. Again, this location is situated in the disputed territory (“ Arunachal Pradesh, India ” or “ South Xizang, China ”). Di et al. (2009: 133) later provided the first illustrated description for a female C. tricostatus from Mêdog County, alongside information on 6 more females. In 2023, a friend of mine, Tongtong, collected another adult female from approximately the same location (29 ° 19 ' 20.6 '' N 95 ° 19 ' 48.4 '' E; iNaturalist, obs. ID = 196900793). Based on the map in Bastawade (2006: 450), the following additional localities are approximated (Fig. 1): Nyingchi City, Zayü County, 28 ° 32 ' 55.2 '' N 96 ° 07 ' 09.7 '' E; Shannan City, Tsona City, 27 ° 18 ' 16.4 '' N 92 ° 32 ' 36.4 '' E, 27 ° 41 ' 34.0 '' N 93 ° 52 ' 57.4 '' E. One record from iNaturalist (obs. ID = 117892140) was reported from Mêdog County (28 ° 06 ' 14.1 '' N 95 ° 00 ' 19.4 '' E), near the first reported Chinese female by Henderson (1913). The specimen was identified as a male C. tricostatus by me based on the rectangular and elongated manus as well as the absence of D 3 (Pocock, 1899: 266). As indicated by the species name, the dichotomous identification of C. tricostatus has been primarily relied upon the presence of only three “ costate ” carinae (D 1, D 4, D 5) on the dorsal surface of its pedipalp chela (e. g., Tikader & Bastawade, 1983: 318; Kovařík, 2000: 70; Kovařík, 2012: 3; Kovařík & Ojanguren-Affilastro, 2013: 132; Di et al., 2013: 88; Di et al., 2014: 14). This species was described based on two males from by Pocock (1899: 266 – 267), who measured a TL of 48 mm for the holotype male, which increased to 50 mm and 52.25 mm in its redescriptions by Pocock (1900: 50) and Tikader & Bastawade (1983: 322) respectively. The type materials were said to be from “ Sadi, in the Khasia Hills ”, likely referred to the Khasi Hills in the Meghalaya State of India. However, Pocock (1900: 50) subsequently changed the locality to “ Sadiya, Assam ”. In a more detailed redescription by Tikader & Bastawade (1983: 326), they included both localities, selecting the second as its type locality (“ … Sadiya (Type locality) Assam; Khasia hills, Meghalaya … ”). Henderson (1913: 131) was the first to describe the female of this species based on 4 specimens from “ Abor country ”. He noticed a sexual dimorphism in ChL / W and carapacial granulation density, which was followed by Kovařík (2000: 62), and the dense granules in females were also concurred by Di et al. (2009: 133). The selected female for description measured 53 mm in TL (Henderson, 1913: 132). The largest female was recorded with a TL of 59.2 mm in Di et al. (op. cit.: tab. 1), who also documented the lowest known female ChL / W (13.7 / 6.2). All sternites were originally described as smooth except for the presence of 4 carinae on VII in Pocock (1899: 266), followed by Henderson (1913: 131), Kovařík (2000: 62), and Kovařík & Ojanguren-Affilastro (2013: 142). In the redescription of this species, Di et al. (2009: 136) described the sternite VII as “ … with some small granules on posterior portion … ” (note that this does not refer to the four granular carinae), suggesting an equivalent state of “ weakly granular ” or “ subgranular ”. However, Yin et al. (2015: tab. 3) simply described it as “ granular ” (logically, a larger set), while they also employed the more specific descriptor, “ weakly granular ”, for other congeners (C. conchiformus and C. mainlingensis). Kovařík (2000: 62) provided a PTC range of 5 – 6 without specifying the sex, likely combined the male count (5 – 6) in Pocock (1899: 267; 1900: 60; however, Tikader & Bastawade (1983: 324) described the male holotype with 5 / 5 pectinal teeth) and the female count (5) in Henderson (1913: 132), whereas Di et al. (2009: tab. 1) further recorded one female pectine with a count of 4. Tikader & Bastawade (1983: 324) were the first to enumerate the cheliceral VAD in this species, providing a count of 8 / 7 for movable / fixed fingers of the holotype male. Later, Bastawade (2006: 454) reported a range of 8 – 9 and 7 – 8 VAD for the cheliceral movable and fixed fingers respectively. Di et al. (2009: 137) recorded a total range of 7 – 11 VAD on the movable finger for the 7 females they examined. Pocock (1899: 267) initially mentioned 11 subrows of denticles on the movable finger of this species based on the holotype male, but then erroneously recorded it with 4 subrows in his redescription (Pocock, 1990: 60). Henderson (1913: 132) reported 10 subrows based on 4 new female specimens from “ Abor country ”. Kraepelin (1913: 142) subsequently keyed this species with as DSC of 10 – 11 (“ … Schrägreihen des beweglichen Fingers 10 – 11 … ”), but later in the same work (op. cit.: 146) diagnosed it as “ … die Zahl der Schrägreihen des beweglichen Fingers beträgt 11 – 12 … ” (“ the number of oblique rows of the movable finger is 11 – 12 ”). Tikader & Bastawade (1983: 324) did not directly provide the count, but illustrated a finger of the male holotype showing 11 subrows (op. cit.: 916), if based on the division by larger granules. Kovařík (2000: 62) accepted the count of 11 – 12, which was later consistently adopted in Di et al. (2009: 133), Kovařík & Ojanguren-Affilastro (2013: 142), Di et al. (2013: 88), Di et al. (2014: 14), and Yin et al. (2015: tab. 3). The count of 10 – 11 was first followed by Bastawade (2006: 454) in his interspecific comparison of C. dibangvalleycus. In his dissertation, Di (2009: 98) keyed this species with a DSC of 10 – 12, but then (op. cit.: 106) diagnosed it as 11 – 12 (as per Di et al. (2009: 133 )), citing Bastawade’s description in the section of C. dibangvalleycus on page 101. The exactly same scenario is found in Sun’s (2010: 101, 103, 108) dissertation. In fact, the two dissertations are generally identical (and both listed C. mainlingensis as their new species). Chaerilus tricostatus is one of the most unique Chinese Chaerilus species (alongside C. conchiformus and C. pictus) for its relatively large size, essentially dark blackish color, and absence of D 3. The strongly sexually dimorphic pedipalp is also distinctive, with males showing long, cuboid chela. According to the diagnostic table summarized herein (Table 1), the presence of 10 – 12 subrows of denticles on pedipalp movable finger would only associate it with C. pictus and C. tessellatus, whose distinctions have been discussed above. The lack of D 3 places it closer to C. dibangvalleycus and C. mainlingensis, from which it can be separated by its higher DSC (vs. 7 – 8 in those two species). It is worth clarifying that D 3 is still observable in the moistened specimen with the aid of light from proper angles (pers. obs.; cf. Di et al., 2009: fig. 1). What gives rise to its apparent absence is but a significant reduction in the relative size of is constitutive granules (Figs. 42 – 43). However, the slightly concave intercarinal surfaces between D 1 and D 3, as well as D 3 and D 4, contribute to identifying the residual presence of D 3.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE013FFFB998F49B5FE1AA8A9.taxon	distribution	DISTRIBUTION. Nyingchi City (Mêdog and Zayü counties) and Shannan City (Tsona City).	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE016FFFB9ADE4ADFFBCBADF7.taxon	description	(Figures 44 – 51; Tables 1 – 2) http: // zoobank. org / urn: lsid: zoobank. org: act: 00 E 2 C 268 - AC 3 C- 4 B 38 - 8801 - 9992 CE 905 FDF	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE016FFFB9ADE4ADFFBCBADF7.taxon	materials_examined	TYPE MATERIAL (Kovařík, 2000: 65). China, TibetAutonomous Region, Nyingchi City, Bomê County, 29 ° 52 ' N 95 ° 45 ' E, 1 ♂ 12 ♀, 1 juv., FKCP. OTHER MATERIAL. China, Tibet Autonomous Region, Nyingchi City, Mêdog County (incorrectly given as “ Nêdong District, Shannan City ” in Di (2009: 106) and Sun (2010: 108 )), Hanmi Village, 29 ° 02 ' N 95 ° 03 ' E (extends to Arunachal Pradesh), 2 ♀, MHBU (Zhu et al., 2008: 47); Nyingchi City, Bomê County, 4 ♀ (Di, 2009: 106). Two ♀ reported in Yin et al. (2015: 46). MATERIAL EXAMINED (VT) [putative; misidentified as C. wrzecionkoi in Tang (2024 b)]. China, Tibet Autonomous Region, Nyingchi City, Bomê County, Tramog Town, 29 ° 51 ' 32.5 '' N 95 ° 46 ' 03.4 '' E, 2859 m a. s. l., 27 th July 2023, 1 ♀, leg. Tongtong (Figs. 44 – 51).	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE016FFFB9ADE4ADFFBCBADF7.taxon	diagnosis	DIAGNOSIS. TL ca. 32.3 mm for ♂ and 30.74 – 44 mm for ♀. General color blackish brown to black. Two pairs of lateral ocelli and one pair of median ocelli. Carapace and tergites granular; CAM straight; sternite III – VI smooth, VII granular and acarinate. Metasoma I – V with carinae 10 - 8 - 8 - 8 - 7. Male telson not strongly elongated. PTC 4 in ♂ and 3 – 4 in ♀. VADC of cheliceral movable / fixed fingers 6 / 4. Pedipalp chela slightly slender in ♂, ChL / W ca. 3.12 in ♂ and 2.6 – 2.91 in ♀; manus with D 1, D 3 – 5, and V 1, 3 present and granular, E and I obsolete; DSC of movable finger 8, dorsal edge of movable finger straight. CURRENT ASSESSMENT OF TAXONOMIC VALIDITY. Valid, but species characterization requires refinement.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE016FFFB9ADE4ADFFBCBADF7.taxon	discussion	REMARKS. This species was the first Chaerilus described from Tibet, on the basis of 1 adult male, 12 adult females, and 1 juvenile. It was contrasted only with C. assamensis given the unique count of finger denticle subrows (8) at the time. The single differential character utilized was the CAM shape (straight in C. tryznai, arched in C. assamensis). After reviewing the original description of C. dibangvalleycus (presumed synonym of C. assamensis as per Kovařík & Ojanguren-Affilastro, 2013), the two species further differ in the VADC of cheliceral fixed finger, D 3 development, and sternite VII (Table 1). However, those differences hold true only if C. dibangvalleycus is indeed synonymous with C. assamensis. Nevertheless, the opposite outcome does not logically negate the difference (based solely on the paper descriptions) between C. dibangvalleycus and C. tryznai. Yin et al. (2015: 46) studied two new female specimens (deposited in USTC, without collection details), increasing the upper TL bound to 44 mm while decreasing the lower ChL / W bound to 2.6. Additional comments for the interspecific difference are given under C. pseudoconchiformus and C. wrzecionkoi. Zhu et al. (2008: 47 – 51) redescribed this species based on the same female from Hanmi Village, Mêdog (Fig. 1), later reported in Di’s dissertation (2009: 106) who mistakenly stated that it was from Nêdong District (in Shannan City) despite providing the same coordinates; illustrations and measurements of the female are identical in Zhu et al. (2008: figs. 45 – 59, tab. 1) and Di (2009: figs. 48 – 50, tab. 5), and the former paper will be referenced to henceforth. Zhu et al. (op. cit.) also listed another female collected one day before from the same locality as the female examined, and the two records were followed by Di et al. (2013: 57). Di (2009: 106) further mentioned 4 females from Bomê without coordinates. All six females were fully documented in Sun’s dissertation (2010: 108), but Di et al. (2013: 57) excluded the four females from Bomê. Not much useful information can be retrieved from the redescription as the key characters were generally identical with the original description. However, Zhu et al. (2008: 50) provided a ChL / W of 2.2 for the female they examined, but measurements from their table 1 would give a value of 2.083 (6.75 / 3.24). A crude measurement based on their figure 47 yields, on the other hand, a ChL / W of 2.54 (to derive width in pixels, a constraint rectangle was applied to the chela figure in situ, i. e., no rotation, and the length was obtained from the pixel distance between fingertip and the most proximal, angular granule on the external margin). This is closer to the original metrics (2.9), and even more so to the lower bound value (2.6) given in Yin et al. (2015: tab. 3).	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE016FFFB9ADE4ADFFBCBADF7.taxon	distribution	DISTRIBUTION. Hanmi Village of Mêdog County, and Bomê County, in Nyingchi City.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE029FFCF9AFD4D72FD91ADF6.taxon	description	(Figures 5 – 10, 68 – 75; Tables 1 – 2) http: // zoobank. org / urn: lsid: zoobank. org: act: C 097 EF 9 A- B 8 A 7 - 4 BF 1 - A 6 BC- 3 E 5416 EF 9 B 29	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE029FFCF9AFD4D72FD91ADF6.taxon	materials_examined	TYPE MATERIAL (Kovařík, 2012: 11). China, Tibet Autonomous Region, Nyingchi City, Bomê County, Tongmai Town, 30 km west of “ Donjung ”, 30 ° 06 ' 06.4 '' N 95 ° 04 ' 47.5 '' E (approximated), 2 ♂ 2 ♀, FKCP. MATERIAL EXAMINED (VT) [putative; misidentified as C. tryznai in Tang (2024 b)]. China, Tibet Autonomous Region, Nyingchi City, Bomê County, Tramog Town, Nyingchi City, Bomê County, 29 ° 58 ' 23.1 '' N 95 ° 39 ' 31.9 '' E, 3849 m. a. s. l., 22 nd July 2019, 1 ♀, leg. Tongtong (Figs. 5 – 10, 68 – 75).	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE029FFCF9AFD4D72FD91ADF6.taxon	diagnosis	DIAGNOSIS. TL ca. 33 – 37 mm for ♂ and 39 – 41 mm for ♀. General color dark brown to blackish. Two pairs of lateral ocelli and one pair of median ocelli. Carapace and tergites granular; CAM straight; sternite III – VI smooth, VII granular and acarinate. Metasoma I – V with carinae 10 - 8 - 8 - 8 - 7. Male telson not strongly elongated. PTC 4 – 5 in ♂ and 3 – 4 in ♀. Pedipalp chela slightly slender in ♂, ChL / W ca. 2.57 in ♂ and 2.37 in ♀; manus with D 1, D 3 – 5, and V 1, 3 present and granular, E and I obsolete; DSC of movable finger 8, dorsal edge of movable finger straight. CURRENT ASSESSMENT OF TAXONOMIC VALIDITY. Valid, but species characterization requires refinement.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE029FFCF9AFD4D72FD91ADF6.taxon	discussion	REMARKS. This species was rather tersely by two pairs of adults. Kovařík (2012: 11) diagnosed this species with a PTC of 3 – 5, but then detailed in his description with a note “ … (females 3 x 4, 1 x 4; males 1 x 4, 3 x 5) … ”. This could be a typographical error, where the first digits represent the number of pectines, aligning with the total pectine count for the four specimens. Therefore, the second digits likely represent the PTC, possibly indicating that one or three female pectines had 4 teeth, while the others had 3 teeth (according to the range in diagnosis). Yin et al. (2015: tab. 3) considered the DSC of the male holotype to be 9, based on Kovařík (2012: fig. 64). The finger illustrated at a low resolution was covered with dirt, preventing a confident enumeration. I reckon at least 8 rows of denticles based on the inner denticles, concurring with Kovařík (op. cit.: 11). Kovařík (op. cit.: 13) briefly compared C. wrzecionkoi with C. mainlingensis and C. tryznai, which were the only resemblant Tibetan congeners at the time (now also C. pseudoconchiformus). A single character was leveraged, the carinae on sternite VII, which are present in C. mainlingensis but absent in C. wrzecionkoi. However, a more reliable character appears to be D 3, which is absent in C. mainlingensis but present in C. wrzecionkoi. The comparison between C. wrzecionkoi and C. tryznai was referenced to the dichotomous keys (No. 19, op. cit.: 2), in which males of C. tryznai possess proportionally narrower chela than C. wrzecionkoi (> 3 vs. <2.6). Based on Kovařík (2000: tab. 1), females of C. tryznai also have narrower chela (2.91 vs. 2.37). Concerns may arise for the potential overlap when taking intraspecific variation and measurement inconsistency into account since the difference was based solely on one ratiometric. Although he examined multiple specimens of both species, no intraspecific variation was documented, which appears to be the author’s regular practice. While experienced authors may defend such a modus operandi, particularly when they can demonstrate having the species for comparison, readers cannot confidently accept their conclusions with a rigorous mindset. This approach leaves them hindered by doubtful diagnostic characters (e. g., ChL / W, as indicated in Figs. 7 – 10). The distinction between these two species are however conspicuous if one were to infer from the presumed adult female specimens examined herein (cf. Figs. 44 – 51, 68 – 75).	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE029FFCF9AFD4D72FD91ADF6.taxon	distribution	DISTRIBUTION. Known only from the type locality; Tongmai Town of Bomê County, in Nyingchi City.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE029FFCF9AFD4D72FD91ADF6.taxon	materials_examined	Morphological investigations into Chaerilus specimens collected from Drepung Nine adult females and 40 adult males (Figs. 108 – 109) of an unidentified Chaerilus species (all had been preserved in 75 % ethanol) were collected from Drepung Township, Mêdog County, the type locality of C. tessellatus. Congeneric species recorded in proximity also include C. tricostatus and C. tryznai (Fig. 1). A cursory examination swiftly ruled out C. tricostatus as a potential match given the well-developed D 3 in all specimens. According to the summarized diagnostics (Table 1), C. tessellatus and C. tryznai should ideally be differentiated by DSC, sternite VII, and metasoma II carinae, since males of C. tessellatus remain unknown. For the purpose of providing a general review of diagnostic traits previously used to differentiate Chinese Chaerilus species, the following characters were examined for the 40 Drepung males: PTC, DSC, ChL / W, CAM, sternite VII, and metasoma II – III carinae. The ventral accessory denticles (VAD) on the cheliceral fingers were not assessed, as the ridged segmental membrane in some specimens hindered manipulation of these structures, which appear to be either variable or nondiagnostic (interspecifically overlapped or with unknown intraspecific variation). Nevertheless, several other examined materials of Chaerilus are provided with photographs of VAD on their cheliceral movable fingers (Figs. 92 – 107). It seems that the varying development degree of those denticles can obstruct unambiguous enumeration. The current analyses were founded upon two assumptions to eschew biases stemming from interspecific and ontogenetic variations: all males were (1) conspecific and (2) adult. Conspecificity was recognized upon observing no potentially meaningful morphological discrepancies apart from size and ChL / W (which will be further analyzed). Maturity was verified based on the coloration (uniformly dark brownish black, except for several evidently discolored specimens), carinae and granule development, and most importantly, the presence of hemispermatophores confirmed from several smallest males, ensuring the absence of any large juveniles that overlap with small adults in size. Given my utter lack of experience with this genus and the specimens’ long-term storage in ethanol that prevented perfect anatomy, identification on the hemispermatophores of small males was inferred from their similarity with the unambiguous hemispermatophores retrieved from the largest male (Figs. 110 – 116). 1. Methodologies	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE029FFCF9AFD4D72FD91ADF6.taxon	description	(1) Carapace length as the primary proxy for total length and the secondary proxy for body size Conceptually, “ size ” is hereby defined as the volume an object occupies within physical space, representing a composite metric that incorporates length, width, and height. For scorpions, size theoretically refers to the total volume of all their segments, including minuscule structures such as setae. In contrast, “ body size (BS) ” exclusively pertains to the combined volume of the prosoma, mesosoma, metasoma, and telson, collectively denoted as the “ body ”. However, the visual impression of a scorpion’s size can be influenced by the relative size of its pedipalps or leg span. For instance, many hormurid species possess massive pedipalps in relation to their body size. Thus, BS is not necessarily an exhaustive representation of the scorpion’s overall size. “ Total length (TL) ”, or “ total body length ” as in Sissom et al. (1990: 217), is the linear measurement along the longitudinal axis of the body (i. e., somatic axis). For practical purposes, TL is frequently used as the primary proxy for BS, as it represents the largest dimension (or “ principal component ”) contributing to the total volume of the scorpion body. The inclusion of chelicerae in body length measurements is predominantly observed in amateur scorpion-rearing circles and occasionally in academic studies (e. g., recently in Sanchez-Piñero et al. (2024: 190 )). While excluding the telson is well justifiable, as this division is not regarded as a true body segment in scorpions (Hjelle, 1990: 8; Lourenço, 2018: 4), chelicerae, being highly movable appendages, cannot reliably guarantee a standard or consistent measurement of body length. Moreover, the degree of cheliceral protrusion varies depending on the state of the specimen, both in vivo and in vitro. The derivation of scorpion TL varies among authors and / or depends on the specific research objectives. A crude, expedient method is to simply measure the linear distance between carapace anterior margin (CAM) and telson tip. The evident issue with this method is that the TL of specimens with an inflated or contracted mesosoma will be either overestimated or underestimated. A more meticulous way entails taking 14 independent segment measurements from carapace to telson, treating each cuticular component separately for mesosoma and metasoma. However, this method can inadvertently amplify the total error due to ambiguities in selecting the initial and terminal points for measurement on each sclerite, as well as the unavoidable imprecision inherent in manual operations. This error becomes evident during repeated measurements of the same specimen by the same practitioner. Suppose each measurement has an associated uncertainty (or variation, error) arising from measurement imprecision, denoted as δ, the total uncertainty in the sum (Δ) is given by: where n is the number of measurements, and δ i is the uncertainty in the i - th measurement. Assuming all measurements share the same δ, the formula simplifies to Δ = (√ 14) ∙ δ ≈ 3.74 ∙ δ. To ensure there is no Δ between two independent measurements on the same specimen, one would need either to eliminate the individual δ entirely, or ensure that all δ cancel each other out. To control Δ under a given threshold k (in mm), each δ must be smaller than k / 3.74 mm (e. g., for k = 1, δ must be less than approximately 267 μm). Achieving this level of precision is highly challenging, if not practically impossible. Owing to the absence of a standardized protocol for accurate linear measurement, and the fact that some specimens exhibited contraction in the mesosoma, the carapace length (CaL) was used in this study as the proxy for TL to avoid cumulative uncertainties propagated through sequential measurements of individual body segments (measurement conducted manually with the aid of a digital caliper by carefully confining the anterior and posterior carapacial margins). Ergo, CaL represents the secondary proxy for BS. In the context of studying intersexual differences, Fox et al. (2015: 14) suggested that CaL itself may exhibit sexual dimorphism and thus be less reliable, recommending the use of metasoma I width (met 1 W) as the TL indicator. It is worth noting that the accuracy of width measurements may also vary depending on the species under study, particularly when the segment lacks nearly parallel bilateral surfaces. Given that the current objective focuses on a single sex and crude visual inspection revealed no significant somatic ratiometric discrepancies among individuals, CaL was chosen as the secondary — with TL being the primary — BS reference, as it is less flexible than carapace width, which is more prone to transverse deformation in preserved specimens, particularly among small species having less rigid cuticle (cf. Tang et al., 2023: fig. 91). However, for multispecies comparisons, CaL can be an unreliable proxy for either TL or BS due to the distinct morphologies (essentially the somatic ratiometrics) exhibited by different species, particularly when compared between sexes if significant sexual dimorphism is present. TL itself, being a one-dimensional linear variable, also does not effectively translate into size (or more precisely, volume), which is a three-dimensional variable. Predictably, few would contend that a 31 cm long cotton thread with a diameter of 2 mm is comparable in size to a 12 - inch pizza or a cylindrical water bucket with a volume of 162 × 31 π cm 3. Overly simplified reduction leads to the significant loss of numerous crucial morphological (profile) information. A species may have a large TL, but this could essentially be the result of a disproportionately elongated metasoma, while the combined volume of its prosoma and mesosoma may be smaller than that of another species sharing the same TL, as the two species may differ in the relative width of mesosoma. For example, both adult female Androctonus gonneti Vachon, 1948 and adult male Lychas scutilus can reach ca. 85 mm in TL, yet the latter appears considerably smaller as a result of its overall slenderness; similarly, both adult male Androctonus turkiyensis Yağmur, 2021 and L. scutilus may have a CaL of ca. 6.6 mm, but the former reaches only 56 mm in TL (Tang, pers. obs.; see the figure gallery of this paper on ResearchGate). Their size discrepancy becomes even more pronounced in vivo when metasoma is curled over mesosoma. This is one of the many fundamental errors made by Forde et al. (2022) (e. g., failing to account for the different sources of LD 50 values and intraspecific variations in morphometrics, and neglecting to include many other non-medically significant species with smaller sizes and chelae, which would virtually nullify their result; it is also questionable regarding how they quantified the size of the chela), who argued that there is a negative correlation between scorpion “ body size ” and venom potency. In a multispecies context, TL, as a biased BS proxy, could potentially be corrected by a weighted average width (W avg). One may partition the scorpion body into two halves, with the upper half comprising prosoma and mesosoma, and the lower half being metasoma. Telson is excluded for convenience in this method, and the redefined TL is denoted as TL ’. The weighted average width is hence given by: where L 1 is the upper length, L 2 is the lower length, Ŵ 1 is the estimated mean upper width, Ŵ 2 is the estimated mean lower width, W ca is the anterior width of carapace, W cp is the posterior width of carapace, W tm is the maximum width of tergite, W min is the minimum width of metasoma, and W max is the maximum width of metasoma. TL ’ can be normalized based on the width contribution. One way to correct the TL ’ for comparison is to use the ratio of weighted average widths: where M is the metric (corrected TL ’) later used for multispecies comparison, and W avg, tot is the mean weighted averaged width of all species under comparison, which is calculated by dividing the sum of all W avg for each (i - th) species by the number of species (n). This correction method implies that it is tailored for specific comparative contexts. Since proxies are utilized for their practical convenience at the expense of compromising precision or accuracy, authors may opt to derive TL ’ by directly measuring the linear distance from CAM to the lateral anal lobe of metasoma V. L 2, attained from the more unstable metasomal segments, can also be obtained by simply subtracting L 1 from TL ’. Additionally, to derive the mean upper width, individual measurements for the anterior and posterior widths of the carapace and each tergite may not be necessary. I propose to use only the anterior and posterior widths of the carapace and the maximum tergite width (e. g., width of tergites IV, V, or VI) for estimation. Similarly, for the mean lower width, it may be sufficient to measure the two metasoma with the minimum and maximum widths, after leveling the segment and applying a constraint rectangle to determine each value. Apparently, this simplified calculation would likely indicate its unsuitability in assessing species with prominently disproportionate metasomal segments (e. g., Apistobuthus Finnegan, 1932, some Microbuthus Kraepelin, 1898, and adult male Jaguajir pintoi (Mello-Leitão, 1932 )). Be that as it may, the final decision hinges on the practitioner’s judgement regarding the tradeoff between time investment and precision. Nevertheless, comparisons (in mm) between true mean metasoma widths (W 2, based on all segments) and min ~ maxaveraged metasoma widths (Ŵ 2) suggested that even for species like Microbuthus spp. and adult male J. pintoi, the simplified calculation proposed herein would not lead to significant deviation from the true mean metasoma width: (1) M. gardneri Lowe, 2010: W 2 2.106 (vs. Ŵ 2 2.115) in holotype male and 2.342 (vs. 2.335) in paratype female (Lowe, 2010: 8 – 9); (2) M. kristensenorum Lowe, 2010: W 2 2.146 (vs. Ŵ 2 2.175) in holotype female and 1.316 (vs. 1.325) in Wadi Shuwaymiyah female (Lowe, 2010: 15); (3) J. pintoi: W 2 6.32 – 7.54 (vs. Ŵ 2 6.25 – 7.4) in two males and 5.94 – 6.76 (vs. 5.9 – 6.7) in two females (Teruel & Tietz, 2008: tab. 1). However, such deviation was notably exaggerated in A. susanae Lourenço, 1998, resulting in overestimations of the true mean metasoma width: W 2 6.622 (vs. Ŵ 2 7.465) in Bostan male and 6.81 (vs. 7.435) in Omidiyeh female (Navidpour & Lowe, 2009: tab. 2). The degree of amplification (Λ = Ŵ 2 / W 2) is 0.98 – 1.01 for Microbuthus and J. pintoi, but approximately 1.1 (1.09 – 1.13) for Apistobuthus. The within-group difference is minimal at around 0.03 for {M. gardneri, M. kristensenorum, J. pintoi}, whereas this difference increases ca. 3 - to 4 - fold to 0.09 – 0.12 when this group is compared against A. susanae. The Λ variation range for {M. gardneri, M. kristensenorum, J. pintoi} falls within the general variability (mean ± SD = 1.005 ± 0.019, n = 172) derived from several buthid species — as other families tend to exhibit even less variability in their metasomal segment widths (most possessing relatively slenderer metasoma) — that exhibit no conspicuously disproportionate metasomal segments: Aegaeobuthus gallianoi (Ythier, 2018), Ananteris ochoai Botero-Trujillo & Flórez, 2011, Anomalobuthus rickmersi Kraepelin, 1900, Androctonus kunti Yağmur, 2023, Androctonus sumericus Al-Khazali & Yağmur, 2023, Barbaracurus exquisitus (Lowe, 2000), Buthacus amitaii Cain et al., 2021, Butheoloides nuer Kovařík, 2015, Butheolus harrisoni Lowe, 2018, Buthus castellano Teruel & Turiel, 2022, Centruroides caribbeanus Teruel & Myers, 2017, Chaneke hofereki Kovařík et al., 2016, Charmus saradieli Kovařík et al., 2016, Compsobuthus satpuraensis Waghe et al., 2022, Gint banfasae Kovařík & Lowe, 2019, Grosphus angulatus Lowe & Kovařík, 2022, Heteroctenus turieli Teruel & Yong, 2023, Hottentotta gibaensis Kovařík, 2015, Ischnotelson peruassu Esposito et al., 2017, Isometrus kovariki Sulakhe et al., 2020, Janalychas granulatus Mirza, 2020, Lanzatus huluul Kovařík & Lowe, 2021, Leiurus macroctenus Lowe et al., 2014, Lychas mucronatus (Fabricius, 1798), Mesobuthus bogdoensis (Birula, 1896), Microcharmusantongil Lourençoetal., 2019, Microtityus adriki Moreno-González et al., 2024, Neobuthus amoudensis Kovařík et al., 2018, Odontobuthus persicus Barahoei & Shahi, 2024, Olivierus gorelovi (Fet et al., 2018), Orthochiroides somalilandus Kovařík & Lowe, 2022, Orthochirus fomichevi Kovařík et al., 2019, Parabuthus robustus Kovařík et al., 2019, Physoctonus debilis (C. L. Koch, 1840), Pseudouroplectes jacki Lourenço, 2021, Razianus farzanpayi Tahir et al., 2014, Reddyanus jayarathnei Kovařík et al., 2016, Rhopalurus ochoai Esposito et al., 2017 (one female paratype metasoma IV width corrected to 4.9), Somalibuthus sabae Kovařík & Njoroge, 2021, Somalicharmus whitmanae Kovařík, 1998, Teruelius haeckeli Lowe & Kovařík, 2022, Thaicharmus lowei Kovařík et al., 2007, Tityobuthus mariejeanneae Lourenço et al., 2018, Tityopsis rolandoi Kovarik et al., 2024, Tityus (Tityus) achilles Laborieux, 2024, Tityus (Atreus) moralensis Moreno-González et al., 2022, Tityus (Caribetityus) schrammi Teruel & Santos, 2018, Tityus (Archaeotityus) wachteli Kovařík et al., 2015, Troglorhopalurus translucidus Lourenço et al., 2004, Trypanothacus barnesi Lowe et al., 2019, Uroplectes malawicus Prendini, 2015, Xenobuthus xanthus Lowe, 2018, and Zabius gaucho Acosta et al., 2008 (raw width data retrieved from their respective original or redescription papers, assuming no severe errors). It turned out that the investigated buthids generally tend to increase their metasoma width progressively in both directions, or show slight dilation at segment III or VI, facilitating quick visual determination of the two segments selected for calculating the estimated mean metasoma width in practice. It can also be noticed that some data provided by the authors were affected by manual imprecision based on their discordance with the illustrations, or the relatively high intraspecific fluctuations (maximum Λ difference ~ 0.08 seen in M. adriki, followed by 0.06 in T. translucidus); achieving precision is important as a few authors often leverage ratiometric differences in metasoma for species delimitation. The overall fitness (Pearson’s r = 0.9996, RMSE = 0.048, MAE = 0.036; WSR p = 0.1006, effect size = 0.1245; nonnormal dataset (p <0.0001), n = 180, including Microbuthus and Jaguajir) supports Ŵ 2 as a relatively suitable estimator for true mean metasoma width. In extreme cases such as Apistobuthus spp., a possible approach is to treat the enlarged segment (metasoma II) as a separate entity for calculation. This would entail dividing the lower half into segments II and {I, III, IV, V}, measuring the length of segment II (as only this measurement is required), and calculating their respective mean widths. Based on the empirical data (the same A. susanae data as before), this approach, albeit reducing overestimation to some extent, still led to deviations from the true mean metasoma width (true values: L 2 W 2 314.2 in male, 322 in female; basic estimation: L 2 Ŵ 2 354.2 in male, 351.5 in female; revised estimation: L 2 Ŵ 2 ’ 328.9 in male, 332.3 in female). An alternative correction involves applying an empirical scaling factor, k, to L 2 Ŵ 2 in the basic formula. This factor can be determined by the inverse of Λ, which equals 0.887 in the male and 0.916 in the female. Averaging these values gives k = 0.9. Multiplying L 2 Ŵ 2 by k results in 318.8 for male and 316.4 for female. The above methodology does not factor in the variability in somatic depth across different species for two primary reasons: (1) the depth of the prosoma or mesosoma is highly flexible and influenced by the individual scorpion’s condition (e. g., states of gestation, starvation, and hydration); and (2) depth generally contributes less to the total volume of the scorpion, with the exception of certain dorsoventrally compressed and / or lithophilic crevice dwellers (e. g., genera Chiromachetes Pocock, 1899, Hadogenes Kraepelin, 1894, Hormurus Thorell, 1876, Hormiops Fage, 1933, Liocheles Sundevall, 1833, Palaeocheloctonus Lourenço, 1996, etc.). In the absence of other information, CaL or TL alone cannot be regarded reliable for representing the actual BS of a species of a random sex in a comparative context. Further studies are needed to assess how sensitive multispecies comparison results are to these biases and whether similar mathematical corrections can mitigate them. A more laborious approach would involve measuring all segments of the scorpion, followed by the use of dimension reduction algorithms (e. g., Principal Component Analysis) to obtain the first principal component, which captures the majority of the information contributing to BS. Alternatively, since metasoma tends to be more morphologically erratic within the order, the estimation of BS (under another definition) could be confined solely to the more conservative prosoma and mesosoma. In any case, a refined measurement protocol for each body segment is requisite before obtaining the raw values that are used to further calculate the TL or mean widths. When the present paper was in press, a meticulous study on various size predictive proxies for scorpions while taking phylogenetic relationships into account was published. Foerster (2025: 9) demonstrated that the length of metasoma V (met 5 L) was the best proxy for TL in buthids, followed closely by CaL (RMSE difference = 0.05; op. cit.: tab. 2). The general accuracy of using met 5 L as a TL predictor was confirmed for both sexes, also with no significant interaction with sex observed among other studied predictors (op. cit.: fig. 3). The primary potential concern is the methodological discrepancy in measurements (as also acknowledged by the author; op. cit.: 4), since most morphometric data were sourced from past taxonomic studies by different authors. According to his diagram (op. cit.: fig. 1), met 5 L was measured dorsally based on the visible anterior and posterior boundaries of the segment. While the posterior boundary may be consistently represented by the lateral lobe of the anal arch among authors (unless some pivoted to leverage the ventral boundary of the anal arch), the anterior boundary can vary depending on the specimen’s orientation, leading to different measurements. As discussed earlier, each metasomal segment has a base section that can be partially concealed within its anterior segment. The least biased point is likely the most proximal end (or anywhere near it that is located more proximally) of the median lateral carina for metasoma V (and the dorsolateral carina for I – IV). Although these technical considerations may seem overly fastidious, the potential measurement bias they introduce might have contributed to the slight difference in TL prediction accuracy between met 5 L and CaL. In practice, CaL is easier to measure given the clearer boundaries compared to the more irregular metasomal segments.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE04BFFAE9B104CD2FD50ADD6.taxon	description	(Figures 52 – 67, 146 – 210; Table 3) http: // zoobank. org / urn: lsid: zoobank. org: act: 2 F 4 C 89 D 9 - 914 B- 487 A-BDCD- 3 CDF 125877 F 8	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE04BFFAE9B104CD2FD50ADD6.taxon	materials_examined	TYPE LOCALITY AND TYPE DEPOSITORY. China, Tibet Autonomous Region, Nyingchi City, Mêdog County, Drepung Township, from Dergong Village (29 ° 10 ' 45.0 '' N 95 ° 08 ' 28.6 '' E; 1702 m a. s. l.) to Gelin Village (29 ° 10 ' 57.7 '' N 95 ° 08 ' 50.7 '' E; 1668 m a. s. l.); VT. TYPE MATERIAL. China, Tibet Autonomous Region, Nyingchi City, Mêdog County, Drepung Township, from Dergong Village (29 ° 10 ' 45.0 '' N 95 ° 08 ' 28.6 '' E; 1702 m a. s. l.) to Gelin Village (29 ° 10 ' 57.7 '' N 95 ° 08 ' 50.7 '' E; 1668 m a. s. l.), June 2024, 1 ♀ (holotype), 40 ♂ 8 ♀, 2 juv. ♀ (paratypes), leg. AC. ADDITIONAL MATERIAL. China, Tibet Autonomous Region, Nyingchi City, Mêdog County, Drepung Township, Dergong Village (29 ° 10 ' 45.0 '' N 95 ° 08 ' 28.6 '' E; 1702 m a. s. l.), June 2024, 1 ♂ (PTC - / 5) 1 ♀ (PTC 4 / 4), leg. AC [in 95 % ethanol when received, now in 99 % ethanol; not examined in detail due to rigidity, will be sent to Czech Republic (FKCP) for molecular analysis]; Mêdog County, June 2024, 2 ♀, purchased dried specimens, allegedly from a recent expedition to this county, collector unknown (Figs. 52 – 67).	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE04BFFAE9B104CD2FD50ADD6.taxon	etymology	ETYMOLOGY. The specific epithet is a noun in apposition, referring to the extraordinary female scientist “ Herta ” from the game Honkai: Star Rail. The name is presumably derived from the German goddess “ Nerþuz ”, meaning “ power, vitality, force ”, herein alluding to the robustness in both sexes of the new species and the evolutionary tenacity of this genus. The transliterated name of Herta in Chinese (ª Ḅ; hēi tǎ) directly translates to “ black tower ”, denoting the dark coloration of the new species. Chinese equivalent: ª Ḅṅfflx.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE04BFFAE9B104CD2FD50ADD6.taxon	diagnosis	DIAGNOSIS. TL ca. 41 – 53 mm for ♂ and 44 – 49 mm for ♀. General color dark reddish to brownish black, pectines yellowish brown. Two pairs of lateral ocelli and one pair of median ocelli. Carapace and tergites granular; CAM slightly concave, or straight, or slightly convex; sternite III – VI smooth, VII granular (except for the anteromedian region) and often bicarinate (coarser and barely tetracarinate in ♀). Metasoma I – V with complete carinae 10 - 8 - 8 - 8 - 7; median lateral carinae on II – IV restricted to the distal 1 / 2 – 1 / 3. Male telson not strongly elongated. PTC 5 – 6 in ♂ and 4 – 5 (rarely 5) in ♀. VADC of cheliceral movable / fixed fingers ca. 6 – 10 / 5 – 7 (pooled range of holotype ♀ and allotypic paratype ♂). Pedipalp chela typically sexually dimorphic, elongated in males (size-correlated), ChL / W (left-right averaged) ca. 3.21 – 3.92 in ♂ and 2.85 – 3.22 in ♀; manus with D 1, D 3 – 5, and V 1, 3 pronounced and granular, E obsolete, I distally incomplete; DSC of movable finger 9 – 10, dorsal edge of movable finger straight. CURRENT ASSESSMENT OF TAXONOMIC VALIDITY. Inconclusive until female topotypes of C. tessellatus with a DSC of 11 and a PTC of 5 are available for morphological and molecular analyses; or, valid, if C. tessellatus truly lacks D 3 (whether conspecific with C. tricostatus or not). The holotype of the new species is designated as female to allow for direct comparison with the holotype of C. tessellatus if the latter is ever rediscovered.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE04BFFAE9B104CD2FD50ADD6.taxon	description	DESCRIPTION. Based on the holotype ♀ (Figs. 146 – 147), and the allotypic paratype male is illustrated in Figs. 148 – 149, 152 – 153, 157 – 159, 169 – 177, 182 – 185, 190 – 192, 198 – 201. Description for the coloration is omitted as the specimen was preserved in ethanol, albeit lacking pronounced discoloration. All structures were photographed under white light as prolonged UV exposure would further decrease the relatively weak fluorescence in this species, but with additional UV fluorescence imaging applied to the pedipalp movable finger. Metasoma of the holotype female and allotypic paratype male were straightened by inserting a thin needle running through all segments to facilitate photography, which caused exudates at the anus in Figs. 191 – 192. Detailed structures taken under white light were placed on a grey background to clearly reveal the numerous white, fluorescent setae. Prosoma (Figs. 150 – 151, 154, 178 – 179). One pair of median ocelli situated on a rounded ocular tubercle, lacking interocular sulcus; one pair of Type 2 A lateral ocelli (each with a pair of MLMa and PLMa); an amber-colored eyespot present underneath PLMa. Carapace isosceles trapezoid in shape, with distinctly increased width posteriorly; anterior margin essentially straight; surface coarsely granular, moderate granules concentrated anteriorly, enlarged granules constitute a pair of oblique carinae extending medially to posteriorly; two pairs of symmetrical, agranular sulci present anterior and posterior to median ocelli; posterolateral surfaces with larger agranular patches. Coxapophyses I distolaterally expanded and angular; sternum pentagonal with a posterior depression. Chelicerae dorsally granular with dark reticulation, a cluster of thick, long setae present at the base of fixed finger; ventrally densely hirsute, setae thick, long, curved, covering the median area of manus and extending to both fingers; basal denticle absent on the left fixed finger but present on the right. Mesosoma (Figs. 150 – 151, 155 – 156). Tergites densely adorned by fine granules, slightly enlarge posteriorly; symmetrical agranular patches present, variable in shape and coverage; all tergites lack discernable carinae. Genital operculum bipartite, genital papillae absent; pectinal plate with highly convex posterior margin; pectines small, with unpartitioned lamella, well-developed fulcra, and large teeth. Pleural membrane covered with infuscate, punctiform microsclerites. Sternites III – IV essentially smooth but matte, except for a few emergent subtle granules present medially to posteriorly, lateral and posterior margins covered by both fluorescent and non-fluorescent setae; sternite V posteriorly with a smooth, reflective, biconvex area; sternite VII granular except for the medial to anterior regions, with a pair of internal carinae formed by enlarged granules; spiracles small and circular. Metasoma and telson (Figs. 186 – 189). Metasoma: Sparsely hirsute and granular; segments I – V with 10 - 8 - 8 - 8 - 7 complete, serrated carinae, formed by enlarged, discrete granules; median lateral carinae partially present distally on II – IV; ventromedian carina distally bifurcate on V; lateral and ventral intercarinal surfaces granular, dorsal surface essentially smooth; anal arch strongly arcuate with extended and flared lateral lobes armed by large, sharp granules. Telson: Pyriform and subgranular, with fluorescent microsetae; lateral surfaces of vesicle with a shallow, wide sulcus; vesicle distinctly tappers distally; aculeus smooth and weakly curved. Pedipalps (Figs. 160 – 168, 180 – 181). Femur: Essentially with 3 discernable carinae formed by large, discrete granules (retrodorsal, retroventral, proventral), prodorsal carina obscured by prolateral granules; retrodorsal and retroventral carinae proximally internal to a short articular carina; dorsal and ventral surfaces granular, retrolateral surface smooth; 5 and 4 trichobothria on dorsal and retrolateral surfaces. Patella: Essentially with 7 discernable carinae formed by large, discrete granules (prodorsal, dorsomedian, retrodorsal, retromedian, retroventral, proventral, promedian), granules larger on retroventral and proventral carinae; prodorsal and retrodorsal carinae distally incomplete, dorsomedian carina proximally incomplete; intercarinal surfaces finely and sparsely granular; dorsal surface with a pronounced distal depression; 3 (id, d 1 – 2), 7 (est 1 – 2, esb, eb 1 – 2, em, et) and 4 (v 1 – 3, iv) trichobothria on dorsal, retrolateral, and ventral surfaces, trichobothrium id anterior to prodorsal carina. Chela: All 7 carinae (D 1, D 3 – 5, E, V 1,3, I) present but vary in development degree; granules forming D 1, D 3 – 4, and V 1,3 larger, flatter, and more continuous; E obsolete, formed by small, random granules; I fades out distally; intercarinal surfaces finely granular dorsally, externally and internally, weaker ventrally; 3 (Eb 3, db, dt), 8 (Eb 1 – 2, Est, Et, eb, esb, est, et), 1 (V) and 2 (ib, it) trichobothria on dorsal, external, ventral, and internal surfaces; dorsal edge of movable finger without proximal lobe. Legs (Figs. 194 – 197). All legs essentially acarinate, sparsely and finely granular; tibial spur absent; tarsomeres with sparse dorsal but dense ventral setae. Basitarsus: A retrolateral row of robust spinules present on I – II, reduced in number on III, absent on IV; a ventromedian row of thinner, denser spinules present I – II (flanked bilaterally by two rows of setae), reduced in number on III – IV; a pair of long pedal spurs present on all legs. Telotarsus: a ventromedian row of short spinules present on all legs, flanked bilaterally by two rows of setae. Apotele: Tarsal ungues stout and curved; dactyl weakly developed. MEASUREMENTS. See Table 3. Measurements for the mesosoma are largely approximate. ONTOGENETIC VARIATIONS. The larger immature female displayed a somewhat tetracarinate sternite VII, distinguishable by the stronger fluorescence of the enlarged granules and its relatively smooth surface (Fig. 206). This observation likely suggests The PTC range in both sexes associates this species with C. that the bauplan of sternite VII in female C. herta sp. n. may assamensis (and C. dibangvalleycus), C. pictus, C. tessellatus, inherently be tetracarinate, though in adults, the external pair and C. tricostatus. It can be distinguished from C. assamensis appears obscured by the more developed peripheral granules. (and C. dibangvalleycus), C. pictus, and C. tessellatus by its consistently intermediate DSC. Between males, it can also AFFINITIES. Since this population has already been thoroughly be differentiated from C. pictus by its short telson. From C. examined and compared in the preceding sections, the tricostatus, it differs by its well-developed D 3. Distinctions in following discussion will be concise and based solely on the D 3 and CPM from C. tessellatus remain indeterminate. summarized data in Table 1. Overall, a combination of PTC The lower bound in its DSC range associates it with C. 5 – 6 in ♂ and 4 – 5 in ♀, DSC 9 – 10, and well-developed D 3 pseudoconchiformus, from which it can be differentiated by is exclusive across the Chinese congeners. The macroscopic a notably larger body size, slightly higher female PTC, and morphology and dark coloration place it closely to C. carinate sternite VII in females. The upper bound associates it tricostatus (cf. Figs. 36 – 43 and Di et al., 2009: figs. 1 – 2). with C. tricostatus, which has been compared above. The well-developed D 3 associates it with all Chinese congeners except C. mainlingensis and C. tricostatus (and possibly C. dibangvalleycus). Among the remaining species not previously compared, namely C. conchiformus, C. tryznai, and C. wrzecionkoi, it can be most confidently distinguished by different chela morphology, consistently higher DSC, and carinate sternite VII in females, respectively.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
111A5C1AE04BFFAE9B104CD2FD50ADD6.taxon	distribution	DISTRIBUTION. Known only from the type locality, likely extends to Arunachal Pradesh. However, a recent observation by my friend Tongtong (iNaturalist obs. ID = 196900794; 29 ° 19 ' 30.8 " N 95 ° 19 ' 58.9 " E) suggests the presence of a presumably conspecific male — identified by its pronounced D 3 carina — just 1 km from the C. tricostatus population documented by Di et al. (2009: 133). Due to my friend’s busy schedule, I have not personally examined this specimen prior to the publication of this paper.	en	Tang, Victoria (2025): Current challenges and preliminary morphological reassessment of the genus Chaerilus Simon, 1877 in China (Scorpiones: Chaerilidae). Euscorpius 406: 1-89, DOI: 10.5281/zenodo.16963598
