Strigamia xizangensis Jiang & Yu, 2025

Yu, Yifei, You, Chunxue & Jiang, Chao, 2025, Taxonomy of the Strigamia centipedes from the East Asian mainland (Geophilomorpha, Geophilidae), Zoosystematics and Evolution 101 (4), pp. 2065-2101 : 2065-2101

Strigamia xizangensis Jiang & Yu sp. nov.

Figs 1 K , 13

Material examined.

Holotype. China • ♂ ( CMMI 20240724005 D ), Xizang Autonomous Region, Yadong County, Lower Yadong Town, Xiongchumo Scenic Area ( 27.3150°N, 89.0070°E), 2190 m asl.; 24. vii. 2024, leg. Chao Jiang & Qing Li .

Paratype. China • 1 ♀ ( CMMI 20240723003 D ), Xizang Autonomous Region, Yadong County, Lower Yadong Town, Pangda Village ( 27.3620°N, 88.9750°E), 2810 m asl.; 23. vii. 2024, leg. Chao Jiang & Qing Li .

Other materials.

China • 1 ♂ ( CMMI 20240715008 D ), Xizang Autonomous Region, Cuona County, Le Menba Ethnic Town, Le Hydropower Station ( 27.8200°N, 91.7460°E), 2490 m asl.; 15. vii. 2024, leg. Chao Jiang & Qing Li ; • 1 ♀ ( CMMI 20240720007 D ), Xigazê, Yadong County, Shangyadong Town, G 562 National Highway ( 27.5480°N, 89.0000°E), 3460 m asl.; 20. vii. 2024, leg. Chao Jiang ; • 1 ♂ ( CMMI 20240307030 D ), Nyingchi, Bomi County, Qinduo Town ( 30.0947°N, 95.7032°E), 2850 m asl.; 7. iii. 2024, leg. Chao Jiang .

Diagnosis.

Body length reaching at least 13 mm; number of leg-bearing segments usually 37–41; with transverse suture on the cephalic plate; cephalic pleurite evidently with sparse setae; with 10 pectinate hyaline teeth in the mandible; anterior margin of the second maxillae coxosternite nearly straight; telopodite and coxal projection of the first maxillae are almost equal in length; basal denticle of tarsungulum cylindrical, convex distal margin with rounded contour; calyx of poison gland ca. 2.5 times as long as wide, situated in the distal half of trochanteroprefemur; metasternites with sparse setae of various sizes; pore-fields not on the anterior part; metasternites without mid-longitudinal deep sulcus; distinct sulcus separating pretergite and intercalary pleurites of the ultimate leg-bearing segment; metasternite of the ultimate leg-bearing segment smooth, with no concave on each side; coxal pores at least 3 on each coxopleuron, sparse on the ventral surface but densely in lateral margin of the metasternite.

Description.

General features. Body 13–20 ( ♂), 19 ( ♀) mm long; with 37–39 ( ♂), 41 ( ♀) leg-bearing segments; narrowing forward and towards the posterior tip. Color (in ethanol 75 %) shallow orange; forcipules darker.

Cephalic capsule (Fig. 13 A, C ) sub-quadratic; ca. 1.1–1.2 times as wide as long; all margins convex; areolation uniform on the entire surface, less sclerotized along an distinct transverse suture; setae arranged scattered. Clypeus with rather uniform areolation; sclerotized along the anterior margin and a median triangular area; fading close to the labrum and the paraclypeal sutures; 1 + 1 post-antennal setae aligned in two longitudinal rows on the anterior part of the clypeus, grouped in the medial part, no medial prelabral setae. Labrum slightly projecting backwards medially, without distinct mid-piece; marginal denticles absent, with two unordered rows of long slender hyaline filaments along the entire labral margin and further rows of shorter filaments behind.

Antennae (Fig. 13 B ) almost uniform in width; ca. 3.0 times as long as the width of the head. Basal articles only slightly more elongated (article II ca. 0.9 times as long as wide); distal articles stouter (article XIII ca. 0.8 times as long as wide); article XIV ca. 1.9 times as long as wide. Setae gradually denser and shorter from the basal articles to the distal ones. Articles I – XIII with two basal whorled long setae along with numerous short setae; remaining articles equipped solely with short setae.

Mandible (Fig. 13 D ) with a single pectinate lamella with ca. 10 hyaline teeth.

First maxillae (Fig. 13 E ). Coxosternite entire; uniformly areolate; without lappets; 3 + 3 setae on anterior middle part. Coxal projection sub-triangular; wider than long; ventral side setae indistinct; dorsal surface with numerous small sensilla on distal half. Telopodite as long as the coxal projection; distinctly articulated; without lappets; ventral side with 2 + 2 long setae on distal half; dorsal surface with numerous small sensilla on distal half.

Second maxillae (Fig. 13 E ). Coxosternite entire; uniformly areolate; anterior margin nearly straight; 1 + 2 small setae close to the anterior margin. Telopodite composed of three articles; gradually narrowing towards the tip; claws simple; almost straight and gradually tapering on the telopodite.

Forcipular segment (Fig. 13 F ). Tergite sub-trapezoid; with lateral margins convex and subparallel; ca. 3.0 times as wide as long. Coxosternite ca. 1.7 times as wide as long on exposed part; anterior margin moderately projecting with respect to its condyles; anterior border approximately straight medially; coxopleural sutures strongly converging backward. Trochanteroprefemur ca. 1.6 times as wide as long; basal distance between trochanteroprefemora ca. 0.4 times of their basal breadth. Forcipular intermediate articles with slight projections. Tarsungulum ca. 2.4 times as long as wide. Basal denticle of tarsungulum cylindrical, convex distal margin with rounded contour, basal margin quite straight and ca. 0.3 times as long as the basal breadth of the tarsungulum. Distal part of the tarsungulum uniformly tapering, its internal margin uniformly curved moderately concave and converging uniformly to the external margin. Calyx of poison gland ca. 2.5 times as long as wide, situated in the distal half of trochanteroprefemur.

Leg-bearing segments (Fig. 13 G ). Tergite 1 wider than metatergite 2; lateral margins converging backward. Metasternites sub-rectangular; without a deeply mid-longitudinal sulcus. Posterior pair of sub-ovoid pore-fields present in all metasternites from 1 to penultimate. Pore-fields present also on all procoxae and metacoxae from 1 to penultimate. Legs 1 smaller than the others; pretarsus claw-like, reaching ca. 1 / 3 of the length of the tarsus.

Ultimate leg-bearing segment (Fig. 13 H – K ). Pretergite and intercalary pleurites separated by distinct sulcus; pretergite ca. 2.3 times as wide as long on exposed part. Metatergite ca. 1.3 times as wide as long; sub-trapezoid. Metasternite edge is indistinct; ca. 1.1 times as wide as long; lateral margins slightly concave to nearly straight, converging backwards; posterior margin ca. 0.2 times as wide as anterior margin; with sparse setae of various sizes. Coxal pores 3–7 ( ♂), 5 ( ♀) on each coxopleuron; opening independently; all sparse on the ventral surface but densely in lateral margin of the metasternite and some of them covered by that; diameter of the coxal pores similar to that of the respective ducts; male setae slightly denser close to the ventral posterior edge of the coxopleuron, female sparse. Ultimate leg ca. 0.9 times as long as penultimate leg, male distinctly swollen, ventral and lateral sides with very dense setae, female sparse. Ultimate pretarsus a claw; ca. 0.3 times as long as tarsus.

Postpedal segments (Fig. 13 H, J ). Male: intermediate sternite distinct and exposed; first genital sternite separated from pleurites by distinct sutures; gonopods bi-articulate, with setae; penis conical; anal pores indistinct. Female: intermediate sternite indistinct, medially not exposed; first genital pleurosternite ca. 2.2 times as wide as long, posterior margin slightly concave, uniformly with sparse setae; gonopods lamina not distinctly bilobate, with sparse setae; anal pores present.

Etymology.

The specific epithet is derived from the Xizang Autonomous Region, the type locality of this species. We suggest the Chinese common name as “ 西藏地蜈蚣 ”.

Remarks.

The morphology of the coxal pores of this species is similar to that of S. nana Bonato, Bortolin, Drago, Orlando, Dányi, 2017 (Fig. 3 G, I ). However, this new species can be distinguished from S. nana based on the characteristics of the anterior margin of the second maxillae, the number of post-antennal setae on the anterior part of the clypeus, the number of leg-bearing segments, and the number of coxal pores. S. nana has a distinguished, widely concave anterior margin of the second maxillae, three post-antennal setae on the anterior part of the clypeus, up to 35 leg-bearing segments, and up to 5 coxal pores on each coxopleuron ( Bonato et al. 2017). In the examined specimen, the mandible of this new species had approximately 10 hyaline teeth with 2 distinct short teeth anteriorly, a characteristic not found in other species.

Distribution.

China ( Xizang Autonomous Region).

Figures

Figure 1. Forcipular segments of Strigamia spp. (A – M). A. S. svenhedini (Verhoeff, 1933) (spm. CMMI 20220903086); B. S. japonica (Verhoeff, 1935) (spm. CMMI 20231128001 D); C. S. tenuiungulata (Takakuwa, 1938) (spm. CMMI 20230414002 D); D. S. bicolor Shinohara, 1981 (spm. CMMI 20210227106); E. S. platydentata Shinohara, 1981 (spm. CMMI 20210702003 D); F. S. korsosi Bonato, Bortolin, Drago, Orlando, Dányi, 2017 (spm. CMMI 20191031044); G. S. laterisetosa sp. nov., holotype; H. S. longiglanda sp. nov., holotype; I. S. dianguiensis sp. nov., holotype; J. S. obliquidentata sp. nov., holotype; K. S. xizangensis sp. nov., paratype; L. S. ziyunensis sp. nov., holotype; M. S. asiatica sp. nov., holotype. N, O. live specimens of S. laterisetosa (Zhoushan, Zhejiang Province, China; photo by Chao Jiang). Scale bars: 250 μm (A – M).

Figure 3. Strigamia japonica (Verhoeff, 1935). A. Cephalic plate, dorsal; B. Right antenna, ventral; C. Anterior part of cephalic capsule, ventral (forcipules, maxillae and mandibles removed); D. Mandible; E. Maxillary complex, ventral; F. Forcipular segment, ventral (venom canal drawn with dashed lines); G. Sternum of leg-bearing segment, ventral (setae on left part omitted); H. Posterior end of body in adult female, ventral (setae on left coxopleuron and ultimate leg omitted); I. Ditto, dorsal; J. Posterior end of body in adult male, ventral (setae on right coxopleuron and ultimate leg omitted); K. Ditto, dorsal (setae on left coxopleuron and ultimate leg omitted). Areolation drawn in part in A, D, E. Specimens: ♂ (CMMI 20210603169) (G, J – K); ♀ (CMMI 20231128001 D) (A – F, H, I). Scale bars: 100 μm (B – E); 250 μm (A, F – K).

Figure 13. Strigamia xizangensis sp. nov. A. Cephalic plate, dorsal (most part of antennae, legs omitted); B. Left antenna, ventral; C. Anterior part of cephalic capsule, ventral (forcipules, maxillae and mandibles removed); D. Mandible; E. Maxillary complex, ventral; F. Forcipular segment, ventral (venom canal drawn with dashed lines); G. Sternum of leg-bearing segment, ventral (setae on right part omitted); H. Posterior end of body in adult male, ventral (setae on left coxopleuron and ultimate leg omitted); I. Ditto, dorsal; J. Posterior end of body in adult female, ventral (setae on right coxopleuron and ultimate leg omitted); K. Ditto, dorsal. Areolation drawn in part in C. Specimens: holotype (A – H, K); paratype (I), ♀ (CMMI 20240723003 D). Scale bars: 250 μm.