taxonID	type	description	language	source
03E61A39FFC0442C77B4AE3EFD16EA1E.taxon	diagnosis	Diagnosis (following Raven 1985). Retrolateral face of chelicerae with short scopula; retrobasal surface with strong paddle setae that act against horizontally aligned thorn setae on opposing face of prolateral maxillae.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC0442C77B4AE3EFD16EA1E.taxon	distribution	Distribution. Endemic to Southeast Asia.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC0442D77B4A836FB14E86E.taxon	type_taxon	Type species: Magnacrus taynguyenensis gen. nov. sp. nov.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC0442D77B4A836FB14E86E.taxon	etymology	Etymology. The generic name is a combination of Latin words “ magna ” (feminine adjective, meaning “ large ”) and “ crus ” (gender neutral noun meaning “ leg ”), reflecting the significantly thicker leg IV of the species females currently included. The gender is masculine.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC0442D77B4A836FB14E86E.taxon	diagnosis	Diagnosis. Magnacrus gen. nov. and Citharognathus both exhibit modified (enlarged to some extent) posterior legs in females (Figs 4 A, 8 A, 12 A). However, Magnacrus gen. nov. can be distinguished from all other genera of Ornithoctoninae, including Citharognathus, based on the following features in females: (1) the presence of spinules on the carapace on the posterior edge (Figs 13 C – D); (2) the presence of a setal brush on the retrolateral side of leg IV, formed by conspicuously elongated setae of the patella to metatarsus (Figs 1 C, 4 A, 7 C, 8 A). These features are absent in both sexes of any other ornithoctonine genera (including Citharognathus), and are therefore considered putatively synapomorphic for Magnacrus. In females of Magnacrus, the patellae, tibiae, and metatarsi of legs III and IV are all relatively thicker and more robust than those in the legs I and II (Figs 4 A, 8 A), which is distinct from females of Citharognathus, where only the middle part of tibia IV is slightly enlarged (Fig. 9 C). Magnacrus lacks spinules above the suture of the palpal coxa (Figs 1 E, 2 E, 5 E, 7 E), a feature that aligns it with Cyriopagopus and distinguishes them from all remaining genera (Fig. 10 E). However, aside from the putative synapomorphies mentioned above, Magnacrus can be further distinguished from Cyriopagopus by the following: Magnacrus lacks a dense fringe of long white hairs above the retrolateral cheliceral scopulae and has a reduced number of spines on metatarsus IV (no more than 5 spines). In contrast, species of Cyriopagopus either possess such a fringe on the cheliceral scopulae (C. schmidti group) or always have more than 6 spines on metatarsus IV (C. minax group). The LRF of female Magnacrus is below 90, whereas females of other ornithoctonine genera are consistently above 90, with the exception of Cyriopagopus longipes (von Wirth & Striffler, 2005) (LRF ~ 85).	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC0442D77B4A836FB14E86E.taxon	description	Description. Medium to large spiders (34 – 55 mm) with remarkably thickened rear legs in females, which have a more or less dense brush of longer hairs on the tibiae retrolaterally. Carapace elongated oval, with small spines in the marginal dorsal-basal area. Caput raised in females. Eye group elongated oval or roundish oval, wider than long, ocular tubercle well defined. Clypeus distinct. Labium wider than long. Labiosternal groove with two distinct mounds. Cuspules 67 – 106 in the sub-apical region of the labium. Maxillae longer than wide, overall setose, prolateral anterior angle distinctly produced, serrula absent. Chelicerae retrolateral with a large field of feathered setae. In the basal-dorsal region, the setae are more pronounced. In the basal-ventral region, some of these setae are feathered and sword-shaped. Prolateral face of maxilla consists of diffusely arranged spines. Sternum longer than wide. Legs moderately stout, hirsute, spines present on tibiae and metatarsi I – IV. Abdomen roundish oval, with very weak pattern. Spermathecae undivided with distinct dent in middle. Tibial apophysis of males apically numerous bristled.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC0442D77B4A836FB14E86E.taxon	distribution	Distribution. China (?); Vietnam (Fig. 17). Biogeography. Based on the first author’s field observations, all specimens of M. tongmianensis from Vietnam were collected or observed at elevations below 600 m above sea level. In contrast, the new species M. taynguyenensis was collected at elevations higher than 1000 m above sea level, suggesting a distinct altitudinal distribution pattern among members of the genus Magnacrus.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC0442D77B4A836FB14E86E.taxon	discussion	Remark. Based on the examination of nearly all type species of ornithoctonine genera by Volker von Wirth, the presence of spines above the prolateral palp coxa suture are recognized as a synapomorphy. This character may be useful for dividing the subfamily Ornithoctoninae into two major clades. However, the result will be published in a separate study. Although, Magnacrus tongmianensis (Zhu, Li & Song, 2002) gen. nov. comb. nov., was original described under the genus Citharognathus, the new genus Magnacrus is separated from Citharognathus by: both male and female specimens of new genus without spines above the prolateral palp coxa suture (Figs 1 E, 2 E, 5 E, 7 E) vs. present in Citharognathus (Figs 9 E, 10 E); in females, there is a unique dense setal brush on the metatarsus of leg IV retrolaterally (Figs 4 A, 8 A) while absent in Citharognathus (Fig. 12 A); there are no spinules on the carapace in Citharognathus (Fig. 9 A); the strongly incrassate patella, tibia and metatarsus of legs III and IV compared to legs I and II (Figs 4 A, 8 A) while in Citharognathus only the tibia of leg IV is incrassate (Fig. 12 A); there are numerous short, stout black spinules on patellae, tibiae and metatarsi of leg III & IV in C. hosei (Figs 9 C, 12 A, 13 B), but absent in the new genus Magnacrus. Additionally, male Citharognathus possess distinct long dense setae on all legs and abdomen (Fig. 12 B) while this feature is less distinct in male Magnacrus (Figs 4 B, 8 B). Thus, we propose the new ornithortonine genus Magnacrus gen. nov., to accommodate the new combination M. tongmianensis (Zhu, Li & Song, 2002) gen. nov. comb. nov., and the new species M. taynguyenensis gen. nov. sp. nov., both from Vietnam. Additionally, the two genera show differences in both distribution and lifestyle species as Magnacrus are currently known only from the Central Highlands of Vietnam and are typical ground-dwelling spiders (Figs 14 A – D, 15 A – B), whereas the type species of Citharognathus, C. hosei, is an arboreal species distributed in northern Borneo (Fig. 16 A – B). Although both genera show an incrassate tibia of leg IV, the thickened posterior legs are not rare for Theraphosids, and this trait is usually of multiple independent origins, such as those genera of the theraphosinae, Eupalaestrus Pocock, 1901, Crassicrus Reichling & West, 1996 (Reichling & West 1996; Borges et al. 2021). At first glance, this feature seems to closely link Magnacrus and Citharognathus. However, the presence of spinules above the maxillary suture and the presence of numerous short, stout black spinules on patella, tibia and metatarsus of leg III & IV in Citharognathus (Figs 9 C, 12 A, 13 B) as well as their geographical distribution and lifestyle, suggest that their phylogenetic positions are actually quite distant from each other (Wendt et al. in prep.)	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC1442477B4AAE6FF74EA0A.taxon	description	(Figs 1 – 4, 13 D, 14, 17)	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC1442477B4AAE6FF74EA0A.taxon	materials_examined	Type materials. Holotype ♀ (MHBU-Ar. T 0029) and paratype 1 ♀ (MHBU-Ar. T 0030), CHINA: Guangxi, Ningming Co., Tongmian Township (21 ° 46 ’ N, 107 ° 19 ’ E), 15 January 2002, leg. Tinghui Li (MHBU, examined). Other materials examined. 1 ♂ (TNU-THE- 0005) & 1 ♀ (TNU-THE- 0002), VIETNAM: Đ ắk L ắk Province: Ea Kar District, Cu Elang (TNU), leg. Quang Duy Hoang; 1 ♀, Vietnam (SMF); 1 ♂ (SMNS-Aran- 001565) & 4 ♀♀ (TNU-THE- 0001, 0003, 0007; SMNS-Aran- 001566), VIETNAM: Đ ắk L ắk Province, leg. Quang Duy Hoang.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC1442477B4AAE6FF74EA0A.taxon	diagnosis	Diagnosis. Females of Magnacrus tongmianensis can be easily distinguished from M. taynguyenensis gen. nov. sp. nov., by the following: (1) scopula on met. IV well developed and divided (fig. 2 H in Zhu et al. 2002 and fig. 2 F in Zhu & Zhang 2008) vs. weakly developed, undivided (Fig. 13 A); (2) stridulatory spines on the prolateral palp coxa with 17 spines in M. tongmianensis (Fig. 1 E) while 10 spines in M. taynguyenensis (Fig. 7 E); (3) the notch in the middle of the undivided spermatheca (Fig. 1 D) in the M. tongmianensis is shallow compared to M. taynguyenensis (Fig. 7 D). Palpal male of M. tongmianensis with 7 keels (PS, PA, PSA, PI, RB, A, SA) and a distinct VTM (Fig. 3 A – F) vs. five keels (PS, PA, PI, SA, A) and without VTM (Fig. 6 A – F) in M. taynguyenensis; M. tongmianensis with two spines on the ventral tibia I apically (Fig. 2 D) vs. absent in M. taynguyenensis (Fig. 5 D); ERF in M. tongmianensis is ca. 33 (Fig. 3 F) while M. taynguyenensis is above 40 (Fig. 6 F).	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC1442477B4AAE6FF74EA0A.taxon	description	Description of male (TNU-THE- 005). Body length: 44.5 (including chelicerae). Color (in life) (Fig. 4 B): Femora of legs dark brown, rest of front legs light brown, tips of metatarsi and tarsi dark brown. Legs dorsally with distinct elongated beige stripes. Carapace and abdomen brown. Carapace (Fig. 2 A): length 17.0, width 14.5. Fovea low, Fovea: 1.87 wide, curve length 1.89, slightly recurved. Chelicerae (Fig. 2 F): length 9.5, width 6.0. strong, reddish setal fringe along promargin. Clypeus: width 0.63, smaller than width of OT. Eyes: OT length 2.19, width 2.56. Anterior row almost straight, posterior row slightly procurved. Diameter (longitudinal) ALE: 0.62; AME: 0.68; PLE: 0.53, PME: 0.58; inter-distances: ALE – AME: 0.17; AME – AME: 0.33; PLE – PME: 0.03; Maxillae (Fig. 2 E): length (incl. trochanter) 11.0. Prolaterally plano-convex, anterior prolateral lobe wellpronounced. Retrolateral face mostly glabrous. Prolateral face with a stridulating organ consisting of 20 thorn-like black spines pointing forward and increasing in length and size from posterior to anterior and dorsal to ventral, in three rows; of these, 4 small thorn-like spines are located between the actual spine arrangement and the suture. Fine plumose setae above suture intermixed with four longish spiniform setae, dorso-anterior edge with a row of elongated black spiniform setae. Labium: length 2.87, width 1.81, wider posteriorly, anterior and posterior edge procurved. Many small black cuspules (~ 67). Sternum (Fig. 2 B): length 8.09, width 6.70. Wider posteriorly than anteriorly, with a thin intermix of short setae and sparse longer setae, more so along edges. No spines on edges, but thicker setae along opposing edges of coxa IV. Sternal sigilla: three pairs (not including labio-sternal sigilla), glabrous, PSS largest, ovoid, length 0.80, 0.84 from sternum edge, 3.04 between PSS and clearly visible. Middle and anterior pair obscured by setae, middle pair smaller than PSS and anterior pair smaller than middle pair. Labiosternal groove: glabrous, slightly narrower medially, groove with low oblong cuticular mound on either side of medial narrowing. Leg setation: all legs covered with short pile setae with scattered longer guard setae. Leg I & IV tibia with pro and retrolateral fringe of short pile setae. Legs: formula I, IV, II, III. LRF ~ 101. Leg lengths (fem., pat., tib., met., tar., total): I 16.5, 8.5, 16.0, 13.0, 9.5, 63.5. II 16.0, 6.5, 12.5, 11.5, 8.0, 54.5. III 13.0, 6.0, 9.0, 10.5, 9.0, 47.5. IV 17.0, 6.0, 15.0, 17.0, 8.0, 63.0. Tar. IV uniform without transverse pallid medial suture. Tibia apophysis on leg I ventral with a single prolateral apophysis with numerous spines at its tip (Fig. 2 C – D). Scopula: met. I – III and tar. I – IV, undivided; met. IV divided. Met. I: 88 %; II: 73 %; III: 54 %; IV: 41 %. Coxae: coxae I – IV covered ventrally with fine setae, intermixed with longer darker setae, apically, darker basally. Leg I almost as long as IV, 1.17 times the length of II. IV widest, not as rectangular as III. Prolateral margins of II – IV, retrolateral margins of I – IV and apical ventral margins of I – IV, increasing from anterior to posterior, with longer setae, absent along prolateral margin of I. Ventral measurements for coxa + trochanter: length: I 12; II 11; III 10; IV 11. Fine plumose setae on prolateral face, intermixed with numerous elongated black spiniform setae. Spines: Leg: I Tib. 1 v, a, rl; 1 v, a, pl; Met. 1 v, a, pl; 1 v, a, m; II Tib. 1 v, a, rl; 1 v, a. pl; Met. 1 v, a, rl; 1 v, a, m; 1 v, a, pl; III Tib. 1 v, a, pl; 1 v, a, rl; Met. 1 d, a, pl; 1 d, a, rl; 1 v, a, pl; 1 v, a, m; 1 v, a, rl; IV Tib. 1 v, a, pl; 1 v, a, rl.; Met. 1 v, sm, pl; 1, v, a, pl; 2 v, a, m.; 1 v, a, rl. Claws: all unarmed, no third claw on leg IV. Abdomen: length 18.0, wide: 13.0 Palpal bulb (Fig. 3 A – F): Embolus with seven keels, PS, PA, PSA, PI, RB, A and SA keel, tegulum ventrally basal with a bulge-like process (VTM), ERF ~ 33. Spinnerets: PMS: length 0.98; PLS: length 5.42. Additional description to female (TNU-THE- 00002). Body length: 55 (including chelicerae). Color (in life) (Fig. 4 A): Femora of legs dark brown, rest of front legs light brown, rear legs gray brown, carapace light beige, opisthosoma gray brown. Patella, tibia and metatarsus IV retrolaterally with a dense fringe of longer reddish setae. Femur I have a retroventral fringe of short dense red setae. Carapace (Fig. 1 A): length 20.5, width 15.5. Fovea: 2.38 wide, 2.45 curved length, procurved. Chelicerae (Fig. 1 F): length 11.0, width 4.0. Retrolaterally with a large field of plumose setae, baso-dorsally with a smaller field of strong plumose setae, baso-ventrally with 5 long, sword-shaped plumose setae. Clypeus: width 0.8, clearly smaller than width of OT. Eyes: OT length 2.20, width 3.12. Diameter (longitudinal) ALE: 0.81; AME: 0.73; PLE: 0.64, PME: 0.59; inter-distances: ALE – AME: 0.34; ALE – PLE: 0.24; PLE – PME: 0.15; PME – AME: 0.14; AME – AME: 0.41. Maxillae (Fig. 1 E): length (incl. trochanter) 12.09. Prolaterally plano-convex, anterior prolateral lobe wellpronounced. Retrolateral face mostly glabrous. Prolateral face with 17 short thorn-like black spines pointing forward and increasing in length and size from posterior to anterior, in two rows, fine plumose setae above suture, dorso-anterior edge with a row of 11 elongated black spiniform setae. Labium: length 2.34, width 2.83. 88 cuspules in anterior area of labium. Sternum (Fig. 1 B): length 10.16, width 7.86. Wider posteriorly than anteriorly, with a thin intermix of short setae and sparse longer setae, more so along edges. No spines on edges, but thicker setae along opposing edges of coxa IV. Sternal sigilla: three pairs (not including labio-sternal sigilla), glabrous, PSS largest, ovoid, length 1.15, 0.77 from sternum edge, 3.53 between PSS and clearly visible. Middle and anterior pair obscured by setae, middle pair smaller than PSS and anterior pair smaller than middle pair. Labiosternal groove: glabrous, slightly narrower medially. Leg setation: all legs covered with short pile setae with scattered longer guard setae. Leg IV patella, tibia and metatarsus with dense retrolateral brush of longer guard setae (Figs 1 C, 4 A). Legs: formula IV, I, II, III. LRF ~ 85. Leg lengths (fem., pat., tib., met., tar., total): palp 12.0, 7.0, 7.5, –, 7.5, 34; I 14.0, 8.0, 11.0, 8.0, 7.5, 48.5; II 12.0, 7.0, 8.0, 8.0, 6.5, 41.5; III 12.0, 6.5, 6.0, 7.5, 6.0, 38; IV 16.0, 8.0, 14.0, 13.0, 6.0, 57. Pat., Tib. + Met. of leg III and IV strongly incrassate. Tar. IV uniform without transverse pallid medial suture. Scopula: met. and tar. I – IV, undivided. Met. I: 75 %; II: 68 %; III: 60 %; IV: 45 %. Coxae: coxae I – IV covered ventrally with fine setae, intermixed with longer darker setae, apically, darker basally. Leg I almost as long as IV, 1.17 times the length of II. IV widest, not as rectangular as III. Prolateral margins of II – IV, retrolateral margins of I – IV and apical ventral margins of I – IV, increasing from anterior to posterior, with longer setae, absent along prolateral margin of I. Ventral measurements for coxae + trochanter: length: I – 13; II – 12; III – 10; IV – 13. Spines: Palp Tib.: 1 v, a, rl; 2 v, a, pl; Leg: I Tib.: 1 v, a, pl; Met.: 1 v, a, m; II Tib.: 1 v, a, rl; Met.: 1 v, a, rl; 1 v, a, m; 1 v, a, pl; III Tib.: 1 v, a, rl; 1 v, a, pl; Met.: 1 d, a, rl; 1 d, a, pl; 1 v, a, rl; 2 v, a, m; IV Tib.: 1 v, a, rl; 4 v. a, pl (other Leg: 2 v, a, pl); Met.: 1 d, a, pl; 1 v, sm, pl; 1 v, m, pl (other Leg: 1 v, sm, pl; 1 v, sa, pl); 6 v, a, rl; 5 v, a, pl. Claws: all unarmed, no third claw on leg IV. Abdomen: length 20, wide: 20. Genitalia (Fig. 1 D): Spermatheca undivided and consisting of two lobes connected by a dent in the middle. Width 4.11, height at the highest point of the left lobe 0.94, of the right lobe also 0.94, at the lowest point in the middle 0.63. The angle between the two lobes is 133.43 °. Spinnerets: PMS: 1.59; PLS: length 7.74. Natural history. Specimens of M. tongmianensis were collected from low elevations (below 600 m elev.). The once existing tropical deciduous lowland forest in the region now consists mainly of agricultural development (corn, tangerines) with rubber plantations and small fragmented secondary forests (Fig. 14 A). The self-excavated fossorial retreats of M. tongmianensis were found on gently sloped ground amongst shaded vegetation in clay-like soil at the fringes of secondary forest or plantations at an elevation of 500 meters. Retreats of adult females averaged 5 cm in diameter and 40 cm in length and ran somewhat parallel under the ground surface, unbranched, curving upwards and ending in a blind chamber (Fig. 14 C). M. tongmianensis incorporates surrounding organic debris with silk around the entrance rim of the retreat. What is remarkable here is the arrangement of foliage and leaves around the burrow entrance. These are often arranged in such a way that rainwater flows past the burrow entrance due to the arrangement of the leaves and thus does not enter the burrow. A similar arrangement of leaves at the burrow entrance was observed with Cyriopagopus doriae (Thorell, 1890) in Borneo. There, too, rainwater was prevented from entering the burrows by the roof-like arrangement of leaves at the burrow entrance (Koh 2024). Occupied retreats are usually silken over by day, possibly to prevent predacious ants and wasps from entering (Fig. 14 B). When extracted from the retreat, M. tongmianensis will become very defensive and readily bite if further provoked (Fig. 14 D). Nothing is known about the life cycle of M. tongmianensis. Males were found wandering in July and it is suspected this is the breeding season for this species, during the highest rainy season from June through to the end of August in the Central Highlands of Vietnam (Q. D. Hoang & T. D. Nguyen, pers. obs.). Ethnozoology. A local ethnic mix of Kinh and Mnong people call these spiders Nh ện lông which means ‘ hairy spider’ and treat them with mixed ideas. Some local people reported the venomous bite from this spider will kill a water buffalo, but without evidence, while other people collect, cook and eat these spiders (arachnophagy) with great appeal and as a supplement food source. Taylor (1975) investigated the nutritional values of the tarantula spiders eaten in Cambodia and Laos and found they were 63.4 % protein and 9.8 % fat by body weight. Further, a few village people reported they kill and soak these spiders in wine to make a traditional medicine for rubbing on their skin to cure aches, sprains and bruising (Q. D. Hoang, pers. obs.).	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC1442477B4AAE6FF74EA0A.taxon	distribution	Distribution. China (?); Vietnam (Đ ắk L ắk) (Fig. 17).	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC1442477B4AAE6FF74EA0A.taxon	discussion	Remark. The type locality of M. tongmianensis (Tongmian, China) and the newly reported locality here (Đ ắk L ắk Province, Vietnam) have a distribution gap of over 1,200 kilometers, which is extremely rare throughout the Theraphosidae. Đ ắk L ắk Province belongs to the Tây Nguyên Plateau in central Vietnam and represents a distinct biogeographic region. Although Đ ắk L ắk Province and Tongmian have roughly the same elevation, the annual precipitation, average temperature, and relative humidity in Đ ắk L ắk Province are much higher than those in Tongmian (Weather and Climate 2025). Moreover, from a biogeographic perspective, Tongmian is in southern China, where the fauna and flora closely resemble those of northeastern Vietnam (east of the Red River), but differ significantly from that west of the Red River, which is considered a natural biogeographic barrier (Averyanov et al. 2003; Sterling et al. 2006; Bain & Hurley 2011; Hoang 2025). These facts make the disjunct distribution of this species even more difficult to explain. Tongmian Township, located on the China-Vietnam border, has served as a major transit hub in the cross-border tarantula trade between China and Vietnam for the past two decades. Collectors, after gathering spiders in Vietnam, would converge on Tongmian before shipping their acquisitions, with a single shipment sometimes containing thousands of individuals (Hu et al. 2009). M. tongmianensis was one of the species caught up in this trade. According to private communications between Yu and a local collector in Tongmian, M. tongmianensis were actually collected around the area of Buôn Ma Thu ột City in Vietnam (pers. comm. Yu and local collectors in Tongmian). Moreover, during five separate fieldwork expeditions undertaken by Yu in Tongmian in recent years, not a single specimen of M. tongmianensis was found, and no further information on the species in China has been reported anywhere. Based on the above, we suspect that the type specimens of M. tongmianensis (two females) might have been escaped individuals during the smuggling process and was collected by chance. This species may not have a natural population in China. Its natural population might be endemic to the Central Highlands region of Vietnam.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC8443A77B4A8C2FEF5EAD6.taxon	description	(Figs 5 – 8, 13 A, C, 15, 17)	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC8443A77B4A8C2FEF5EAD6.taxon	materials_examined	Type materials. Holotype ♂ (SMNS Aran- 003985), VIETNAM: Lâm Đ Ồng Province, August 2005, leg. Joe Nielsen; paratypes: 1 ♀ (SMNS Aran- 003986), 1 ♂ (VNMN-ARA-THE- 00011), 1 ♀ (VNMN-ARA-THE- 00012), same data as holotype; 2 ♀♀, South Vietnam, leg. Hombach, in SMF.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC8443A77B4A8C2FEF5EAD6.taxon	etymology	Etymology. The specific epithet is derived from the Tay Nguyen region, the local name for the Central Highlands of Vietnam, where the species was found.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC8443A77B4A8C2FEF5EAD6.taxon	diagnosis	Diagnosis. Females can be distinguished from M. tongmianensis by the following: (1) metatarsus IV of M. taynguyenensis has only a weakly developed scopula which is almost restricted in the ventral apical part and undivided (Fig. 13 A), whereas in M. tongmianensis, scopula on met. IV is relatively well developed, covers about distal half of the ventral surface of met. IV and divided (fig. 2 H in Zhu et al. 2002 and fig. 2 F in Zhu & Zhang 2008); (2) stridulatory spines on the prolateral palp coxa (Fig. 7 E) in M. taynguyenensis are reduced in number (10 spines), compared to M. tongmianensis (17 spines; Fig. 1 E); (3) the long soft setae on retrolateral surface of tibia IV (Fig. 7 C) in the M. taynguyenensis is relatively sparse, whereas those setae are rather dense, forming a brush-like structure in the M. tongmianensis (Fig. 1 C); (4) the notch in the middle of the undivided spermatheca (Fig. 7 D) in the M. taynguyenensis is relatively deeper than those in the M. tongmianensis (Fig. 1 D). In males, M. taynguyenensis can be distinguished from M. tongmianensis by the following: (1) M. taynguyenensis has five main keels (PS, PA, PI, SA, A) on the palpal bulb, without distinct VTM (Fig. 6 A – F), whereas in M. tongmianensis with 7 keels (PS, PA, PSA, PI, RB, A, SA) and a distinct VTM are presented (Fig. 3 A – F); (2) M. taynguyenensis is spineless on the ventral apical part of tibia I (Fig. 5 D), different to M. tongmianensis, which has two spines there (Fig. 2 D); (3) ERF in M. taynguyenensis is clearly above 40 (Fig. 6 F), significantly higher than the ERF in M. tongmianensis (ERF is ca. 33) (Fig. 3 F).	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC8443A77B4A8C2FEF5EAD6.taxon	description	Description of Male holotype, SMNS Aran- 003985, with body length: 34.46 (including chelicerae). Color (in life) (Fig. 8 B): Femora of the legs and palps black, the rest of the legs and palps are gray on the upper side. Joint ring between tibia and metatarsus distinct and whitish, carapace, opisthosoma and cheliceral bases bronze-colored. Carapace (Fig. 5 A): length 14.16, width 11.45. Fovea: 1.58 wide, 1.66 curved length, procurved. Chelicerae (Fig. 5 F): length 7.5, width 5.0. Retrolaterally with a large field of plumose setae, baso-dorsally with a smaller field of long strong plumose setae, baso-ventrally with 5 long, sword-shaped plumose setae. Clypeus: width 0.39, smaller than width of OT. Eyes: OT length 1.81, width 2.46. Diameter (longitudinal) ALE: 0.64; AME: 0.59; PLE: 0.48, PME: 0.38; inter-distances: ALE – AME: 0.24; AME – AME: 0.26; PLE – PME: 0.07. Maxillae (Fig. 5 E): length (incl. trochanter) 7.5. Prolaterally plano-convex, anterior prolateral lobe well pronounced. Retrolateral face mostly glabrous. Prolateral face with 10 short thorn-like black spines and 3 short thorn-like black setae pointing forward and increasing in length and size from posterior to anterior, in two rows, fine plumose setae above suture, dorso-anterior edge with a row of 6 elongated black spiniform setae. Labium: length 1.82, width 2.36. 106 cuspules in anterior area of labium. Sternum (Fig. 5 B): length 6.95, width 3.67. Narrow, wider posteriorly than anteriorly, with a thin intermix of short setae and sparse longer setae, more so along edges. No spines on edges, but thicker setae along opposing edges of coxa IV. Sternal sigilla: three pairs (not including labio-sternal sigilla), glabrous, PSS largest, ovoid, length 0.51, 0.25 from sternum edge, 2.08 between PSS and clearly visible. Middle and anterior pair obscured by setae, middle pair smaller than PSS and anterior pair smaller than middle pair. Labiosternal groove: glabrous, slightly narrower medially, groove with low oblong cuticular mound on either side of medial narrowing. Leg setation: all legs uniformly covered with short pile setae with scattered longer guard setae, unlike male M. tongmianensis. Legs: formula IV, I, II, III. LRF ~ 97. Leg lengths (fem., pat., tib., met., tar., total): I 12.0, 6.5, 11.0, 9.0, 7.0, 45.5; II 10.0, 6.0, 8.0, 7.5.0, 6.0, 37.5; III 9.5, 5.0, 6.0, 7.0, 5.0, 32.5; IV 13.0, 5.0, 12.0, 11.0, 6.0, 47. Tar. IV uniform without transverse pallid medial suture. Tibia apophysis on leg I ventral with a single prolateral apophysis with numerous spines at its tip (Fig. 5 C – D). Scopula: met. and tar. I – IV, undivided. Met. I: 73 %; II: 66 %; III: 51 %; IV: 25 %, all divided by strong setae. Coxae: coxae I – IV. Ventral measurements for coxa + trochanter: length: I – 10; II – 9; III – 7; IV – 7. Spines: Leg: I Met. 1 v, a, m; 1 v, a, rl; II Tib. 1 v, a, rl; Met. 1 v, a, rl; 1 v, a, m; 1 v, a, pl; III Tib. 1 d, a, pl; 1 d, a, rl; Met. 1 d, a, rl, 1 v, a, pl; 1 v, a, m; 1 v, a, rl; IV Tib. 1 v, a, pl; 1 v, a, rl; Met. 1 d, a, rl; 1 v, a, pl; 1 v, a, m; 1 v, a, rl. Claws: all unarmed, no third claw on leg IV. Abdomen: length 12.8, wide: 9.21. Palpal bulb (Fig. 6 A – F): Embolus with four keels, PS, PA, PI, SA and A keel, tegulum ventrally basal without a bulge-like process (VTM), ERF ~ 42. Spinnerets: deformed, not measurable. Description of Female paratype (SMNS Aran- 003986), with body length: 52 (including chelicerae). Color (in life) (Fig. 8 A): Femora of the legs and palps black, the rest of the forelegs, cheliceral bases and palps light brown, the rear legs dark brown, carapace dark gray to black, opisthosoma dark gray. The rear legs have long dense brown setae, especially on retrolateral side from patella to tarsus. Femur I has a retroventral fringe of short dense red setae. Carapace (Fig. 7 A): length 21, width 17. Fovea: 4.96 wide, 5.17 curved length, recurved (Note: This may be a variation that is only present in this specimen, as the fovea is usually procurve, as is the case in the male M. taynguyenensis). Chelicerae (Fig. 7 F): length 12, width 5. Retrolaterally with a large field of plumose setae, baso-dorsally with a smaller field of strong plumose setae, baso-ventrally with 5 long, sword-shaped plumose setae. Clypeus: width 1.79, clearly smaller than width of OT. Eyes: OT length 4.47, width 5.96. Diameter (longitudinal) ALE: 1.45; AME: 1.41; PLE: 1.11, PME: 1.05; inter-distances: ALE – AME: 0.82; AME – AME: 0.63; PLE – PME: 0.27. Maxillae (Fig. 7 E): length (incl. trochanter) 13.21. Prolaterally plano-convex, anterior prolateral lobe well pronounced. Retrolateral face mostly glabrous. Prolateral face with 6 short thorn-like black spines and 4 long thorn-like black setae pointing forward and increasing in length and size from posterior to anterior, in two rows, fine plumose setae above suture, dorso-anterior edge with a row of 9 elongated black spiniform setae. Labium: length 2.46, width 4.12. 77 cuspules in anterior area of labium. Sternum (Fig. 7 B): length 10.38, width 6.94. Wider posteriorly than anteriorly, with a thin intermix of short setae and sparse longer setae, more so along edges. No spines on edges, but thicker setae along opposing edges of coxa IV. Sternal sigilla: three pairs (not including labio-sternal sigilla), glabrous, PSS largest, ovoid, length 0.86, 0.74 from sternum edge, 3.27 between PSS and clearly visible. Middle and anterior pair obscured by setae, middle pair smaller than PSS and anterior pair smaller than middle pair. Labiosternal groove: glabrous, slightly narrower medially, groove with low oblong cuticular mound on either side of medial narrowing. Leg setation: all legs covered with short pile setae with scattered longer guard setae (Figs 7 C, 8 A). Leg III & IV patella, tibia and metatarsus with abundant dorso- and retrolateral guard setae not as dense as found on female M. tongmianensis. Legs: formula IV, I, II, III. LRF ~ 86. Leg lengths (fem., pat., tib., met., tar., total): palp 8.0, 7.0, 7.2, –, 7.0, 29.2; I 14.0, 9.0, 11.0, 7.5, 7.0, 48; II 12.5, 8.0, 8.5, 7.0, 6.0, 42; III 11.5, 7.5, 7.5, 8.0, 5.0, 39.5; IV 15.0, 8.5, 13.0, 13.0, 7.0, 56. Tar. IV uniform without transverse pallid medial suture. Scopula: met. and tar. I – IV, undivided. Met. I: 82 %; II: 75 %; III: 56 %; IV: <5 %. Coxae: coxae I – IV. Ventral measurements for coxa + trochanter: length I – 14; II – 11; III – 11; IV – 12.5. Spines: Palp Met.: 1 v, a, rl; 1 v, a, pl; Leg: I Met.: 1 v, a, rl; 1 v, a, m; II Tib.: 1 v, a, rl; Met.: 1 v, a, rl; 1 v, a, m; 1 v, a, pl; III Tib.: 1 v, a, rl; 1 v, a, pl; Met.: 1 v, a, pl; 1 v, a, m; 1 v, a, rl; IV Tib.: 1 v, a, rl; Met.: 1 d, a, rl; 1 v, sm, rl; 1 v, a, rl; 1 v, a, m; 1 v, a, pl. Claws: all unarmed, no third claw on leg IV. Abdomen: length 20, wide: 20. Genitalia (Fig. 7 D): Spermatheca undivided consisting of two lobes connected by a deep dent in the middle. Width 5.29, height at the highest point of the left lobe 1.06, of the right lobe 1.16, at the lowest point in the middle 0.36. The angle between the two lobes is 98.35 °. Spinnerets: PMS: deformed, not measurable; PLS: length 7.74.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC8443A77B4A8C2FEF5EAD6.taxon	distribution	Distribution. Vietnam (Lâm Đ ồng) (Fig. 17).	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFC8443A77B4A8C2FEF5EAD6.taxon	discussion	Natural history. Type specimens of M. taynguyenensis gen. nov. sp. nov. were collected from relatively high elevations (above 1000 m elev.). The general habitat consists of pine forests with an understory of vegetation consisting of grasses and low bushes (Fig. 15 A). The self-excavated fossorial retreats of M. taynguyenensis were found on gently sloped ground amongst shaded vegetation in clay-like soil on roadside embankments at an elevation of 1400 – 1600 meters (Fig. 15 A). Retreats of adult females averaged 5 cm in diameter and 30 – 40 cm in length and ran downward under the ground surface, unbranched, in an ‘ L’ shape, ending in a blind chamber. The interior length of the burrow was lightly lined with silk. Like M. tongmianensis burrows, M. taynguyenensis incorporates surrounding organic debris, such as grasses and pine needles, with silk to form a trumpet-shaped entrance for the burrow (Fig. 15 B). Occupied burrows are usually silken over by day, possibly to prevent predacious ants and wasps from entering. When extracted from the retreat, M. taynguyenensis will become very defensive and readily bite if further provoked. Nothing is known about the life cycle of M. taynguyenensis. Males have been reported wandering in November and it is suspected this is the breeding season for this species in the Central Highlands of Vietnam (Nielsen, pers. obs.).	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFD6443B77B4A97FFDC8EFEE.taxon	type_taxon	Type species. Citharognathus hosei Pocock, 1895, by monotypy.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFD6443B77B4A97FFDC8EFEE.taxon	etymology	Etymology. Greek cithara κιθάρα, meaning an ancient Greek musical instrument in the lyre or lyra family and Greek gnathos γνᾰ ́ θος, Latinized into gnathus, meaning “ jaw ”, referring to the sound-producing lyra between the opposing faces of the chelicerae and maxillae.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFD6443B77B4A97FFDC8EFEE.taxon	diagnosis	Diagnosis. Females differ from females of the other genera of Ornithoctoninae by having numerous short, stout black spinules on patella, tibia and metatarsus of leg III & IV (Figs 9 C, 12 A, 13 B). Females differ from females of most ornithoctonine genera by having leg IV distinctly longer and thicker than leg I; tibia IV thickest; tibia IV wider than femur IV (except Magnacrus gen. nov.). Citharognathus can be distinguished from Cyriopagopus and Magnacrus gen. nov. by having spines above the suture of the coxa of palp (Fig. 10 E). They can also be distinguished from Cyriopagopus by having fewer than 6 spines on metatarsus IV, and the males can be differentiated by having significantly weaker keels on the embolus than those in the Cyriopagopus (Fig. 11 A – F). They can be distinguished from males of Ornithoctonus because they have a spine on tibia I v, a, rl (Fig. 10 C – D), the keels on the embolus are significantly weaker than in Ornithoctonus and they have no notch on VTM (Fig. 11 A – F). They can be distinguished from males of Taksinus by having a spine on tibia I v, a, rl (Fig. 10 D) and the basal area of the embolus is significantly wider than in Taksinus: ERF between embolus thickness at the base in relation to embolus thickness in the middle of the embolus is 26 in Taksinus (40 in Citharognathus) (Fig. 11 F). They can be distinguished from males of Phormingochilus and Omothymus by the basal area of the embolus which is significantly wider than in males of Citharognathus: ERF between embolus thickness at the base in relation to embolus thickness in the middle of the embolus is less than 32 in males of both genera (40 in Citharognathus) (Fig. 11 F). Males of Citharognathus differ from Lampropelma males in that the apical embolus is not swollen (see Gabriel & Sherwood 2019) and the embolus in dorsal view emerges from the prolateral side of the tegulum (Fig. 11 D, E). In Lampropelma males, the embolus emerges from the retrolateral side.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFD6443B77B4A97FFDC8EFEE.taxon	distribution	Distribution. Malaysia (Borneo).	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFD7443277B4AE67FDBCE92E.taxon	description	(Figs 9 – 12, 13 B, 16 A – B)	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFD7443277B4AE67FDBCE92E.taxon	description	Color (in life) (Fig. 12 A): The basic coloration of the legs is silver-grey with long reddish hairs and the joint rings between the leg segments are all clearly visible and white. Carapace and chelicerae are light gray. Opisthosoma is brown with a clearly visible stripe pattern. Carapace (Fig. 9 A): length 18.0, width 14.5. Fovea low, cephalic region slightly higher than thorax, longer than wide, surface covered with short setae. Fovea: 2.87 wide, 2.95 curved length, procurved, deep, one third narrower than OT. Chelicerae (Fig. 9 F): length 10.0, width 8.0. Strong, reddish setal fringe along promargin. Retrolaterally with a large field of plumose setae, basal with a field of strong plumose setae, baso-ventrally with 5 long, sword-shaped plumose setae. Clypeus: width 0.24, clearly smaller than width of OT. Eyes: OT length 2.57, width 3.79. Anterior row straight, posterior row slightly procuved. Diameter ALE: 0.81; AME: 0.94; PLE: 0.65, PME: 0.56; inter distances: ALE – AME: 0.32; ALE – PLE: 0.25; PLE – PME: 0.10; PME – AME: 0.17; AME – AME: 0.44; MOQ anterior wider than posterior. Maxillae (Fig. 9 E): length (incl. trochanter) 10.55. Prolaterally plano-convex, anterior prolateral lobe well pronounced. Retrolateral face mostly glabrous. Prolateral face with 11 thorn-like black spines pointing forward and increasing in length and size from posterior to anterior and dorsal to ventral, in two rows, some fine plumose setae above suture intermixed with several strong spiniform setae, dorso-anterior edge with a row of 4 elongated black spiniform setae. Labium: length 1.96, width 2.63, 105 cuspules on anterior area of labium. Sternum (Fig. 9 B): length 9.69, width 7.07. Wider posteriorly than anteriorly, with a thin intermix of short setae and sparse longer setae, more so along edges. No spines on edges, but thicker setae along opposing edges of coxa IV. Sternal sigilla: three pairs (not including labio-sternal sigilla), glabrous, PSS largest, ovoid, length 1.21, 1.10 from sternum edge, 2.29 between PSS, PSS and MSS clearly visible. Anterior pair obscured by setae, middle pair smaller than PSS and anterior pair smaller than middle pair. Labiosternal groove: glabrous, slightly narrower medially, groove with low oblong cuticular mound on either side of medial narrowing. Leg setation: All segments distodorsally with short blunt setae. Retrolateral surface of tib. and met. IV with distinct thick pencillate setal fringe, less noticeable on pat., absent on fem.; numerous short stout spiniform setae on patellae, tibiae and metatarsi of leg III and IV (Figs 9 C, 12 A, 13 B). Legs: formula IV, I, II, III (compared from Holotype). LRF ~ 91 (from Holotype, in existing specimen, both leg I are missing). Leg lengths (fem., pat., tib., met., tar., total): palp 9.0, 4.5, 6.0, –, 6.5, 26. I missing. II 11.5, 6.0, 8.5, 7.5, 7.0, 40.5. III 10, 6.0, 6.5, 7.0, 5.5, 35. IV 12.5, 6.0, 10, 9.0, 6.5, 44. Tar. IV uniform without transverse pallid medial suture. Scopula: met. and tar. II – IV, undivided. Met. I: missing; II: 80 %; III: 75 %; IV: 60 %. Coxae: coxae I – IV covered ventrally with fine setae, intermixed with longer darker setae, apically, darker basally. Both leg I missing, IV widest, not as rectangular as III. Prolateral margins of II – IV, retrolateral margins of I – IV and apical ventral margins of I – IV, increasing from anterior to posterior, with longer setae, absent along prolateral margin of I. Ventral measurements for coxae: length – palp 26. Ventral measurements for coxa + trochantera: length; I – missing; II – 9.0; III – 7.5; IV – 8.5. Fine plumose setae on prolateral face, intermixed with numerous elongated black spiniform setae. Spines: Palp Tib.: 4 v, a, pl; 8 v, a, rl; Leg: I missing; III Pat.: 3 v, a, pl; 1 v, a, rl; Tib.: comb of spines a, v, rl + pl; Met.: 2 d, a, rl; IV Tib.: comb of spines a, v, rl + pl; Met.: 2 d, a, rl; 2 d, a, pl. Claws: no third claw on leg IV. Abdomen: length 21, wide: 12. Genitalia (Fig. 9 D): Spermatheca undivided and consisting of two lobes connected by a deep dent in the middle. Width 3.10, height at the highest point of the left lobe 1.08, of the right lobe 1.14, at the lowest point in the middle 0.22. The angle between the two lobes is 81.05 °. Spinnerets: PMS: length 2.51; PLS: length 6.33. Description of Male (SMNS, Aran- 003502), with body length: 30.96 Color (in life) (Fig. 12 B): The overall coloration is fawn brown with longer pale brown setae, darker ventrally. The femora, carapace and chelicerae have a slight intermix of pale pink pubescence. Opisthosoma is brown without any pattern. Carapace (Fig. 10 A): length 11.9, width 10.2. Fovea low, cephalic region higher than thorax, longer than wide, surface covered with short setae. Fovea: 1.0 wide, slightly recurved, deep, almost twice the width of OT. Chelicerae (Fig. 10 F): length 7.0, width 4.4. strong, reddish setal fringe along promargin. Clypeus: width 0.18, smaller than width of OT. Eyes: OT length 2.04, width 2.94. Anterior row straight, posterior row slightly procuved. Diameter ALE: 0.62; AME: 0.85; PLE: 0.57, PME: 0.35; inter distances: ALE – AME: 0.25; ALE – PLE: 0.23; PLE – PME: 0.09; PME – AME: 0.13; AME – AME: 0.20. Maxillae (Fig. 10 E): length (incl. trochanter): 6.97. Prolaterally plano-convex, anterior prolateral lobe well pronounced. Retrolateral face mostly glabrous. Prolateral face with 11 thorn-like black spines pointing forward and increasing in length and size from posterior to anterior and dorsal to ventral, in two rows. Some fine plumose setae above suture intermixed with strong spiniform setae, dorso-anterior edge with a row of 6 elongated black spiniform setae. Labium: length 1.35, width 1.86, wider posteriorly, 85 cuspules in anterior area of labium surface. Sternum (Fig. 10 B): length 6.35, width 4.85. Wider posteriorly than anteriorly, with a thin intermix of short setae and sparse longer setae, more so along edges. No spines on edges, but thicker setae along opposing edges of coxa IV. Sternal sigilla: three pairs (not including labio-sternal sigilla), glabrous, PSS largest, ovoid, length 0.62, 0.42 from sternum edge, 2.28 between PSS and clearly visible. Middle and anterior pair obscured by setae, middle pair smaller than PSS and anterior pair smaller than middle pair. Labiosternal groove: glabrous, slightly narrower medially, groove with low oblong cuticular mound on either side of medial narrowing. Leg setation: All segments distodorsally with short blunt setae. Retrolateral surface of leg IV only with longer hairs. Legs: formula I, IV, II, III. LRF ~ 106. Leg lengths (fem., pat., tib., met., tar., total): palp 8.5, 5.0, 7.5, –, 5.5, 26.5. I 15.5, 8.0, 14, 12, 6.5, 56. II 12, 7.0, 10, 11, 7.0, 47. III 11, 5.0, 9.0, 10, 7.0, 42. IV 15.5, 5.5, 13.5, 12, 6.5, 53. Tar. IV uniform without transverse pallid medial suture. Tibial apophysis on leg I ventral with a single prolateral apophysis with numerous spines at its tip. Scopula: met. I – IV undivided, tar. I – III undivided, tar. IV parted. Met. I: 82 %; II: 79 %; III: 72 %; IV: 54 %. Coxae: coxae I – IV. Ventral measurements for coxa + trochanter length; Palp: 7.24; I – 9.60; II – 8.35; III – 7,29; IV – 8.25. Spines: Leg: I Tib. 1 v, a, rl; II Tib. 1 v, a, rl; Met. 1 v, a, m; 1 v, a, rl; III Tib. 2 v, a, rl; Met. 1 d, a, pl; 1 d, a, rl; 1 v, a, rl; 1 v, a, m; 1 v, a, pl; IV Tib. 1 v, a, pl.; Met. 1 v, a, pl; 1 v, a, m; 1 v, a, rl. Claws: all unarmed, no third claw on leg IV. Abdomen: length 12.06, wide: 7.37 Palpal bulb (Fig. 11 A – F): Embolus with two keels, PS and A, tegulum ventrally basal without a bulge-like process (VTM), ERF ~ 40. Spinnerets: PMS: length 1.11; PLS: length 5.89.	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFD7443277B4AE67FDBCE92E.taxon	distribution	Distribution. Malaysia (Sarawak).	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
03E61A39FFD7443277B4AE67FDBCE92E.taxon	discussion	Natural history. Two populations of C. hosei are known today, both in Sarawak (Borneo). One population is in Bukit Lambir National Park and the nearby area, where they are live sympatrically with Phormingochilus everetti Pocock, 1885 and the other known population is around Long Akah, where they coexist with Phormingochilus pennellhewlettorum Smith & Jacobi, 2015. These spiders live in dipterocarp forests and can typically be found in tree trunk or branch cavities (Fig. 16 A – B) that are strategically sheltered from direct rainfall. This positioning helps prevent excess water from accumulating inside the holes, which could otherwise create unsuitable living conditions. In September, mature males can be found wandering and searching for females. Oviposition is believed to take place around February to April, as one egg sac from which spiderlings had hatched just recently had been found in May (Rossez & Ménart 2024, pers. com.).	en	Hoang, Quang Duy, Yu, Kun, Wendt, Ingo, West, Rick C., Wirth, Volker Von (2025): The new genus Magnacrus (Araneae: Theraphosidae: Ornithoctoninae) from Vietnam, with notes on Citharognathus hosei Pocock, 1895. Zootaxa 5701 (3): 351-381, DOI: 10.11646/zootaxa.5701.3.5, URL: https://doi.org/10.11646/zootaxa.5701.3.5
