Scorpiops matthewi, Tang & Ouyang & Liu & Šťáhlavský, 2024

Tang, Victoria, Ouyang, Kaichen, Liu, Zhenbang & Šťáhlavský, František, 2024, Three new species of genus Scorpiops Peters, 1861 from Tibet, China (Scorpiones: Scorpiopidae), with implications for the diagnostic values of qualitative characters, Euscorpius 394, pp. 1-40 : 21-32

Scorpiops matthewi sp. n.

( Figures 74–107 ; Tables 1–2) http://zoobank.org/urn:lsid:zoobank.org:act:FA7BDC98-

0021-4157-A4AC-0A5BE3405669

TYPE LOCALITY AND TYPE DEPOSITORY. CHINA, Tibet Autonomous Region, Xigazê (or Rikaze, Shigatse) City, Samzhubzê (or Sangzhuzi, Samzhubzêqü) District , 29°16'26.1''N 88°52'38.9''E (29.27390958°N 88.87748148°E), 3897 m a. s. l.; VT .

TYPE MATERIAL. CHINA, Tibet Autonomous Region, Xigazê City, Samzhubzê District , 29°16'26.1''N 88°52'38.9''E, 3897 m a. s. l., 21 July 2023, 1♀ (holotype), 2♀ (paratypes) VT, 1♀ (paratype) , FKCP, leg. Tongtong.

ETYMOLOGY. The specific epithet is a patronym in honor of the American scorpiologist Matthew R. Graham ( Eastern Connecticut State University , Willimantic , Connecticut, USA), who kindly helped the first author in finishing the important revision of Xinjiang Olivierus (Tang et al., 2024) , for his significant contribution to the phylogenetic taxonomy of scorpions. Chinese equivalent: IJ氏ĀH (roughly as “ Matthew’s resemblant scorpion” in English; see Tang (2022a) for the rules of designation) .

DIAGNOSIS. (♀) Total length ca. 60 mm for fmale holotype. Base color uniformly brownish red to blackish brown; chela with fingers and carinae blackish and manus reddish, telson brownish yellow, genital plate and pectines light yellow with pectinal teeth brownish. Cuticular surface irregularly lustrous and finely granular. Carapace with anteromedian notch dome-shaped; ocular tubercle distinct within ocular islet, elliptical in profile; ocular subislets weakly granular and planar; interocular sulcus weak; superciliary carinae smooth. Cheliceral fixed finger with basal and median denticles not forming into a bicuspid trunk. PTC 4–5 in female; pectines form one compact unit with an incomplete furrow between areas where marginal and middle lamellae are usually delimited (P1); fulcra present but weak; sternites III– VI lustrous, VII granular with four distinct carinae. Pedipalp patella with weak prolateral apophysis; 17 (or 15) external and 6–7 ventral trichobothria in fmale. Chela with 4 V series trichobothria; Eb 3 located in proximal half of manus between Dt and Db (type D); Ch-L/W ca. 2.78 in female holotype manus with external secondary carina strongly developed and costate. Dentate margin of movable fingers weakly to moderately undulate in female, with 8–9 OD, 59–71 MD, 20–31 IAD and 6 ID. Telotarsi of leg I– VI with 8–10 stout median ventral spinules nearly in a single row. Metasoma I – V with 10-8-8-8-7 carinae. Telson relatively short and highly bulbous, densely covered with fine granules; T-L/D ca. 2.54 in holotype female; annular ring developed .

DESCRIPTION (♀ holotype).Overall habitus ( Figs. 74–75 ), prosoma, mesosoma, metasoma and telson, chelicera and legs were photographed under white light. Additional UV fluorescence imaging was applied for prosoma and mesosoma. Sparkles presented on the cuticle (prominent in UV photos) due to its highly lustrous texture .

Prosoma and mesosoma ( Figs. 76–85 , 97–98 ). Prosoma: Carapace with 3 pairs of lateral ocelli (two larger, one smaller); median ocular tubercle distinct within ocular islet, elliptical in profile; subislets finely granular, approximately planar; interocular sulcus weak; superciliary carinae smooth. Dorsomedian part of the carapace (ca. 1/2 of total area) planar, without obvious boundary; lateral surfaces slanting downwards. Entire carapace densely covered with fine granules, but highly lustrous at non-granular regions; larger granules concentrated anteriorly at edges flanking anteromedian sulcus, and above and posterior to lateral ocelli; distinct carinae absent. Anterior margin of carapace with a prominent, dome-shaped median notch leading to a shallow, finely granulated anteromedian sulcus; circumocular and posteromedian sulci lustrous; lateral surfaces with a pair of shallow central lateral sulci and prominent posterior lateral sulci, both lustrous; posterior marginal sulcus deep. Chelicerae with dorsal surface smooth and ventral surface moderately setose along the fixed finger; all denticles of cheliceral fingers relatively blunt but might had been caused by abrasion; basal and median denticles on fixed finger not strongly conjoined on a common trunk. Mesosoma: Tergites I–III highly lustrous, VII coarsely granulated and pentacarinate; all tergites covered with small to moderate, somewhat flattened granules, becoming larger closer to posterior margins, with one very weak median carina indicated (more prominent on VI–IV while concealed by random granules on VII). Sternites III–IV highly lustrous, with sparse macrosetae and fluorescent microsetae as well as two axisymmetric, curved furrows; sternite VII strongly granulated with four granular carinae; respiratory spiracles suboval. Genital operculum divided into two halves, without genital papillae at the base. Pectines form one compact unit with incomplete furrow between areas where marginal and middle lamellae are usually delimited; pectine teeth number 7/7; area of peg sensilla concentrated along the external edge of each pectinal tooth; fulcra present but weak; fluorescent microsetae present.

Metasoma and telson ( Figs. 99–102 ). Metasoma sparsely hirsute but densely granulated; carinae formed by larger granules. Metasoma I with 10 carinae, II–IV with 8 carinae, and V with 7 carinae; median lateral carinae of metasoma II– IV decomposed into random granules and do not form distinct carinae; all carinae serrated, especially the ventrolateral and ventromedian carinae on metasoma V. Anal arch armed with sharp granules. Telson lustrous, very sparsely hirsute, proportionally short and very bulbous; dorsal surface adorned by fine granules, other surfaces with denser and larger granules; prominent annular ring developed. Vesicle with lateral surface furnished by one longitudinal sulci close to dorsal surface, and ventral surface with two parallel longitudinal sulci; all four sulci relatively shallow and basically smooth (covered with extremely minute granules). Aculeus smooth, short, weakly curved.

Pedipalps ( Figs. 86–96 ). Pedipalps sparsely hirsute, intercarinal surfaces scattered with small to moderate granules and patches of lattice microstructures. Patella with 17 external (4 et, 4 est, 2 em, 2 esb, 5 eb; one esb closer to em series) and 7 ventral trichobothria. Chela with 4 V series trichobothria; trichobothrium Eb 3 located in proximal half of manus between trichobothria Dt and Db. Femur with 6 highly granular carinae and a densely granulated dorsal surface; retromedian and retroventral carinae incomplete, respectively deconstructed into discrete granules proximally and distally; granules larger on promedian, retrodorsal and proventral carinae. Patella with 5 lustrous, granular or costate carinae and an unevenly granulated dorsal surface; prodorsal carina granular; retrodorsal and proventral carinae costate-granular; retromedian and retroventral carinae costate; granules form a reticulate configuration on ventral surface; prolateral surface with a triangular apophysis armed with four short spiniform granules. Manus densely adorned with small to moderate intercarinal granules, which form a reticulate configuration on dorsal surface; dorsal secondary, subdigital and ventrointernal carinae obsolete, gradually diffusing to dispersed granules; dorsal internal and dorsal marginal carinae nearly fused, formed by irregular granules; digital, external secondary, ventroexternal, ventromedian and interomedian carinae strongly costate and lustrous. Dentate margin of movable fingers moderately undulate (proximal lobe present), adorned by 9/9 OD, ca. 65/71 MD, 27/31 IAD (smaller than MD) and 6/6 ID (3 rd and 4 th ID on right finger each with one additional denticle, marked in pink; also one additional denticle on the outer side); IAD series creates a second row along MD series, several enlarged IAD may be paired with OD distally, which divide both MD and IAD series into several subrows.

Legs ( Figs. 103–106 ). Tibia and tarsomeres of legs with several macrosetae not arranged into bristle combs. Basitarsi of legs I–II with two rows of dense, short spinules, while one row becomes sparser on leg III and absent on leg IV; a pair of pedal spurs present on the distal margin of all basitarsi. Telotarsi of legs I–IV with a row of short, stout ventromedian spinules (8–10 in number) of which two are always paired on the distal end. Ungues moderately short, stout and curved. Carinae on femur and patella either finely granular or costate. Measurements. See Table 1.

VARIATION. The two paratype females examined by the first author were documented with the following values: (1) paratype 1 (finger apically broken, dentition data not included in the diagnosis): PTC 4 /4, ID 4/4, OD 9 /8, MD 61 /67, IAD 18 /16, PVTC 7 /7, PETC 15 (4 et, 3 est, 1 em, 2 esb, 5 eb) / 15(3 et, 4 est, 2 em, 2 esb, 4 eb); (2) paratype 2: PTC 4 /4, ID 6/6, OD 8 /8, MD 59 /61, IAD 23 /20, PVTC 6 /7, PETC 17 (4 et, 4 est, 2 em, 2 esb, 5 eb) /17(4 et, 4 est, 2 em, 2 esb, 5 eb). In all examined specimens, the distal esb always presented on nearly the same level with the two em. Paratype 3 was indirectly examined via the photographs taken by the second author, and its PTC and PVTC were counted as 5/5 and 7/7, respectively. Photographs of the paratypes can be accessed from the supplementary PDF.

AFFINITIES. S. matthewi sp. n. can be confidently differentiated from its two sympatric congeners based on adult females. From S. tibetanus (earlier records suggest its presence in this region but further study is required to confirm the identity; Tang, 2023: 48), it differs as follows: (1) pedipalp chela proportionally larger in comparison to the prosoma ( Fig. 74 vs. Lv & Di, 2022b: fig. 35); (2) pedipalp chela more flattened and elongated ( Figs. 86–87 vs. Lv & Di, 2022b: figs. 61–62); (3) pedipalp patella more elongated with distance between prodorsal and retrodorsal carinae narrower ( Fig. 89 vs. Lv & Di, 2022b: fig. 54); (4) pedipalp femur more elongated with the distance between prodorsal and retrodorsal carinae not prominently increased distally, and retrodorsal carina not strongly undulate ( Fig. 92 vs. Lv & Di, 2022b: fig. 53). From S. lourencoi , it differs as follows: (1) pedipalp chela proportionally larger in comparison to the prosoma ( Fig. 74 vs. Lv & Di, 2022b: fig. 67); (2) pedipalp chela more flattened ( Figs. 87 vs. Lv & Di, 2022b: figs. 94); (3) pedipalp chela not adorned by large, rounded granules ( Figs. 86–87 vs. Lv & Di, 2022b: figs. 93); (4) pedipalp movable finger with stronger proximal lobe ( Fig. 87 vs. Lv & Di, 2022b: figs. 94); (5) pedipalp patella more elongated with distance between prodorsal and retrodorsal carinae narrower ( Fig. 89 vs. Lv & Di, 2022b: fig. 86); (6) pedipalp femur more elongated with the distance between prodorsal and retrodorsal carinae not prominently increased distally, and retrodorsal carina not strongly undulate ( Fig. 92 vs. Lv & Di, 2022b: fig. 85); (7) different pectinal morphology with lower PTC (4 vs. 7–8 in females; Fig. 81 vs. Lv & Di, 2022b: fig. 77). With irrespective to the distribution range, within Tibet, S. matthewi sp. n. most resembles S. ingens from Lhasa by its overall features, including the relatively large and flattened pedipalp chela, proportionally long metasoma and elongated metasoma V (cf. Yin et al., 2015: fig. 3). However, a simple character allows the differentiation where S. ingens exhibits a different pectinal morphology (cf. Yin et al., 2015: fig. 8) with higher PTC (6–8 in females).

Within Xigazê, S. matthewi sp. n. appears to bear a much closer affinity with S. rufus in terms of the females, but several discovered distinctions raise reasonable doubts against considering them conspecific: (1) pedipalp chela proportionally larger in comparison to the prosoma ( Fig. 74 vs. Lv & Di, 2023: fig. 3; ChL/CaL 1.79 in holotype S. matthewi sp. n. and 1.54 in paratype S. rufus ; ChW/CaL 0.64 in holotype S. matthewi sp. n. and 0.6 in paratype S. rufus ); (2) pedipalp chela more flattened ( Fig. 87 vs. Lv & Di, 2023: fig. 32; S. matthewi sp. n. holotype Ch-D’ = 3.72 mm, Ch-L/D’ = 3.83, Ch-L/D = 3.04; S. rufus paratype Ch-L/D = 3.27, probably unstandardized); (3) external secondary carinae of chela composed of a longer, continuous and costate portion before deconstructing into discrete granules ( Fig. 87 vs. Lv & Di, 2023: fig. 32); (4) interomedian carina of chela more straight and longer relative to ventromedian carina (conspicuously shorter and curved proximally in S. rufus ), creating a smaller included angle when they are extended to the distal infinity ( Fig. 88 vs. Lv & Di, 2023: fig. 33); (5) pedipalp patella more flattened with highly developed and costate retromedian carina ( Fig. 90 vs. Lv & Di, 2023: fig. 25); (6) pedipalp femur more elongated with the distance between prodorsal and retrodorsal carinae not prominently increased distally, and retrodorsal carina not strongly undulate ( Fig. 92 vs. Lv & Di, 2023: fig. 23; this is not influenced by the view angle, see other figures of the holotype and the compared species); (7) PTC lower (4–5 vs. 5–6 in females; Fig. 81 vs. Lv & Di, 2023: fig. 15); (8) pectinal fulcra present (vs. absent; Figs. 84 vs. Lv & Di, 2023: 325, fig. 15); (9) distal part of ventral surface outline of telson less convex when viewed laterally ( Fig. 102 vs. Lv & Di, 2023: fig. 22; however, T-L/D contradicts this distinction). Another decisive character lies in the number of IAD on the pedipalp movable finger where numerous denticles (IAD) of unequal sizes are present along the MD series in all examined specimens (3 specimens, 6 fingers) of S. matthewi sp. n. yet such denticles are only paired with OAD in the male S. rufus ( Figs. 95–96 vs. Lv & Di, 2023: fig. 30). While we acknowledge the incomparability between male and female specimens, sexual dimorphism is not known to exist in this regard. With reference to the observation in S. tongtongi , such intersexual discordance only presents in the series posterior to the proximal lobe (Tang, 2023: 8–9). Regrettably, no data was provided for the count of S. rufus in its original description. Geographically, both S. lourencoi and S. matthewi sp. n. are distributed on the south bank of Yarlung Tsangpo River, while S. rufus is on the north thereof (cf. Lv & Di, 2023: fig. 39). However, as no topotypes of the latter species were available for sequencing (and the coordinates for its type locality were also unknown), we cannot molecularly substantiate its validity against S. rufus . Nevertheless, the above listed differences justify it as a distinct species, particularly characters 2–5, 7–8 and number of IAD. The most salient character differentiating the two species is the “flatness” of pedipalp chela, where S. matthewi sp. n. exhibits a conspicuously more flattened chela with fairly narrow intraspecific variation in this regard. Since no specimens of S. rufus were available, the comparability and authenticity of the figures provided by Lv & Di (2023: figs. 28, 32) were confirmed by the chela photos of S. atomatus and S. tibetanus (for which specimens are available) given in Lv & Di (2022b), assuming their photographic setup and procedure remained consistent across papers. Specimens of S. matthewi sp. n. were also examined from different view angles to exclude the potential bias arising therefrom. Ultimately, the credibility of this diagnostic feature was affirmed by the inability to reproduce a similar visual effect of the chela in S. matthewi sp. n. compared to S. rufus .

The description for female S. rufus was founded upon four adults (Lv & Di, 2023: 325). The authors mentioned the following character variations: (1) coloration of female S. rufus (except for the pedipalps) lighter than that of males (Lv & Di, 2023: 328), being yellowish-brown; (2) PVTC: 6/7 (n = 1), 7/7 (n = 1), 7/8 (n = 1) and 8/8 (n = 1); (3) PTC: 5/5 (n = 1), 5/6 (n = 1), 6/5 (n = 1) and 6/6 (n = 1). Similarly, four adult females of S. matthewi sp. n. were documented with the following intraspecific variations: (1) coloration of legs consistently dark brown (vs. orangish brown to reddish brown; cf. Lv & Di, 2023: figs. 35–37); (2) PVTC: 6/7 (n = 1) and 7/7 (n = 3); (3) PTC: 4/4 (n = 3) and 5/5 (n = 1). The difference between the female PTC of two species is statistically significant (two-sample Mann-Whitney U test): p = 0.002108 (when treat all data as independent; n = 8 for each species) or 0.03599 (when take their means; n = 4 for each species). Crucially, this was based on a small sample size, hence the result remains referential. The variations for the two quantitative characters are incorporated into the diagnosis above.

BEHAVIORAL NOTES. The holotype of S. matthewi sp. n. was relatively ferocious and agitated, while also exhibiting a certain proclivity of avoiding threats by fleeing. No adoption of catalepsy was observed. In contrast, the female S. margerisonae was more docile and may remain motionless upon tactile stimulus introduced by finger. It did not promptly seek shelter after being exposed to light, as opposed to S. matthewi sp. n. However, a mere touch by the finger may not incite S. matthewi sp. n. to employ its pedipalp chela for pinching. Nevertheless, the scorpion displayed a defensive posture by opening these appendages.

DISTRIBUTION. Known only from the type locality.

Figures

Figures 74–75. Scorpiops matthewi sp. n., holotype female, habitus in dorsal (74) and ventral (75) views, under white light. Scale bar = 10 mm.

Figures 76–79: Scorpiops matthewi sp. n., holotype female, prosoma and mesosoma. Figures 76–77. In dorsal view, under white (76) and UV (77) light. Figures 78–79. In ventral view, under white (78) and UV (79) light. Scale bar = 10 mm (Figs. 76, 78).

Figures 80–85: Scorpiops matthewi sp. n., holotype female, carapace (80, 83), pectines (81, 84), and sternite VII (82, 85). Figures 80–82. Under white light. Figures 83–85. Under UV light. Scale bar = 5 mm (Fig. 80), 2 mm (Figs. 81–82).

Figures 86–96: Scorpiops matthewi sp. n., holotype female, pedipalp. Figures 86–94. Chela in dorsal (86), external (87), and ventral (88) views, patella in dorsal (89), external (90), and ventral (91) views, femur in dorsal (92), external (93), and ventral (94) views under white light. Figures 95–96. Left (95) and right (96) movable fingers in dorsal view under UV light. Scale bar = 10 mm (Figs. 86–94), 3 mm (Figs. 95–96).

Figures 97–106. Scorpiops matthewi sp. n., holotype female, right chelicera in dorsal (97) and ventral (98) views, metasoma and telson in dorsal (99), lateral (100), and ventral (101) views, telson in lateral view (102), right legs I–IV in retrolateral view (103–106), under white light. Scale bar = 2 mm (Figs. 97–98), 10 mm (Figs. 99–101), 5 mm (Figs. 102 horizontal, 103–106 vertical).

Figures 107–108: Scorpiops spp. in vivo habitus under captive condition. Figure 107. Scorpiops matthewi sp. n., holotype female. Figure 108. Scorpiops margerisonae Kovařík, 2000, subadult (?) female.