Petrobunus chongqing, Zhang & Zhang & Sharma, 2018

Zhang, Chao, Zhang, Feng & Sharma, Prashant P., 2018, Two new species of Petrobunus from China (Opiliones: Laniatores: Petrobunidae), Zootaxa 4524 (1), pp. 51-64 : 52-55

Petrobunus chongqing sp. nov.

( Figs. 1–22 , 37–40 )

Type material. Male holotype, China: Chongqing City, Jinshan Town, Shiti Cave [N 28°56´, E 107°05´], alt. 850m, May 27, 2016, C. Zhang leg. (MHBU-Opi-16 ZC1122 ). One female, paratype (MHBU-Opi-16 ZC1123 ) , same collecting data as holotype.

Diagnosis. Large size (body length> 2 mm); scutal area V, free tergites I and II of male each with a pair of lateral enlarged tubercles; opisthosomal sternite 7 of male with two large setose spines; trochanter IV of male with three mesoventral tubercles; the distal end of ventral plate of arrowhead shape (dorsal view); stylus slender and curved.

Etymology. The specific epithet is a noun in apposition, referring to the type locality.

Description. Male (holotype) habitus as in Figs. 1 , 6 , 15–17 , 21 . Coloration ( Figs. 15–17 ): entire body rusty yellow; carapace and ocularium with blackish brown reticulations; the opisthosomal region of scutum centrally with a upside down cordiform band of blackish brown, which the five areas; both lateral ridges of the scutum blackish brown; free tergites with transverse rows of dark brown stripes; coxae and genital operculum yellow; all free sternites with dark brown bands, somewhat lighter medially; chelicerae and pedipalpi with the same coloration as the dorsum, also with blackish brown reticulate markings dorsally; legs yellow to brown as well as basitarsus, remaining tarsomeres whitish yellow.

Dorsum ( Figs. 1 , 15 ). Dorsal scutum granular and pyriform in shape, widest portion of body at scutal area V. Carapace with two blunt pegs on each side of anterior margin of carapace located near antero-lateral corners. Ocularium unarmed. Scutal sulci of mesotergum indistinct. Scutal area V with a single lateral enlarged tubercle on each side as well as free tergites I and II ( Figs. 1 , 6 ). Anal operculum with numerous scattered granules.

Venter ( Fig. 16 ). Surface of all coxae granulated. Coxa II with a few setose tubercles retrolaterally. Coxa III with prolateral and retrolateral tubercular bridges to adjacent coxae. Coxa IV greatly enlarged, with setose tubercles on anterior margin. Genital operculum sub-triangular. Spiracles not concealed. Opisthosomal sternites 3– 6 each with belt of small regular tubercles. Opisthosomal sternite 7 with two large setose spines directly posteroventrally.

Chelicera ( Figs. 7–9 ). Proximal article with a prominent bulla, but without any conspicuous armament. Second article unarmed, with scattered setae mainly on the prodorsal surface. Fingers relatively short, dentition as illustrated ( Fig. 9 ); movable finger with three teeth; fixed finger with six teeth.

Pedipalp ( Figs. 2, 3 ). Coxa dorsally with two small blunt tubercles. Trochanter ventrally with one short proximal and one long distal setiferous tubercle. Femur ventrally with a row of four setiferous tubercles, two proximal ones being the longest, the medial one being the shortest; on the medial distal side with one setiferous tubercle. Patella with one setiferous tubercle disto-medially. Tibia with two setiferous tubercles mesally; ectally with one short proximal and two long setiferous tubercles. Tarsus with two setiferous tubercles on both sides of ventral surface. Tarsal claw curved and smooth approximately the same length as the tarsus.

Legs ( Figs. 10 , 15–17 ). All segments finely granulated. Trochanter III enlarged. Trochanter IV greatly enlarged, oval in lateral aspect, with three mesoventral tubercles ( Fig 10 ). Femora III–IV curved, especially femur IV. Femur IV with slightly enlarged granules on ventral surface. Patella IV conspicuously incrassated. Patella IV, tibia IV and metatarsus IV ventrally with enlarged tubercles, one near the distal end forming a spine on the tibia IV. Tarsi III–IV with bare double claws, without scopulae. Tarsal claws smooth. Tarsal formula, 3 (2): 5 (3): 5: 5.

Penis ( Figs. 37–40 ) slender, sides nearly parallel along its shaft. Pars distalis well-defined, wider than pars basalis. Distal end of the ventral plate shaped like an arrowhead (dorsal region, not inflatable). Ventral plate with seven pairs of setae on lateral margins. Glans free in apical part, with parastylar lobe extending proximally (not inflatable). Capsula externa cylindrical. Capsula interna small, irregular ovate. The parastylar lobes including one triangular ventral lobe and one bifurcate dorsal lobe. Stylus elongate tubular, and curved.

Female. ( Figs. 4, 5 , 11, 12 , 18–20 , 22 ). In general appearance similar to the male, but lacking lateral enlarged tubercles on scutal area V and on free tergites I and II, and lacking the large setose spines on opisthosomal sternite 7 ( Figs. 4, 5 , 18–20 , 22 ). Leg IV not enlarged and lacking tubercles on coxa through metatarsus ( Fig. 12 ). Cheliceral dentition as illustrated ( Fig. 11 ).

Ovipositor ( Figs. 13, 14 ) composed of two apical lobes, each bearing two dorsal setae, one ventral seta, and two apical setae.

Measurements. Male holotype (female paratype): body 2.24 (2.01) long, prosoma 0.82 (0.80) wide, opisthosoma 1.40 (1.39) wide; length-to-width ratio 1.60 (1.45). Ocularium 0.15 (0.16) long, 0.25 (0.28) wide. Pedipalp claw 0.29 (0.27) long. Penis 1.23 long. Measurements of pedipalp and legs as in Tables 1, 2.

Habitat. The specimens were collected by hand by turning rocks in a small cave about ten meters long.

Distribution. Known only from the type locality ( Fig. 52 ).

Figures

FIGURE 52. Geographic distribution of Petrobunidae taxa.

FIGURES 1–5. Petrobunus chongqing sp. nov. male holotype and female paratype. 1. Male body, dorsal view. 2. Male, left pedipalp, ectal view. 3. Same, medial view. 4. Female body, dorsal view. 5. Same, ventral view. Scale bars: 1 mm (1, 4, 5); 0.5 mm (2, 3).

FIGURES 6–14. Petrobunus chongqing sp. nov. male holotype and female paratype. 6. Male body, lateral view. 7. Male, left chelicera, medial view. 8. Same, ectal view. 9. Male, cheliceral fingers, frontal view. 10. Male, left leg IV, retrolateral view. 11. Female, cheliceral fingers, frontal view. 12. Female, left leg IV, retrolateral view. 13. Ovipositor, dorsal view. 14. Same, ventral view. Scale bars: 1 mm (6, 10, 12); 0.5 mm (7, 8); 0.25 mm (9, 11, 13, 14).

FIGURES 15–20. Photographs of Petrobunus chongqing sp. nov. male holotype and female paratype. 15. Male body and parts of appendages, dorsal view. 16. Same, ventral view. 17. Same, lateral view. 18. Female body and parts of appendages, dorsal view. 19. Same, ventral view. 20. Same, lateral view. Scale bars: 1 mm (17, 20); 0.5 mm (15, 16, 18, 19).

FIGURES 21–22. Live habitus of Petrobunus chongqing sp. nov.. 21. Male holotype. 22. Female paratype.

FIGURES 37–45. Penis. 37–40. Petrobunus chongqing sp. nov. holotype, 41–45. Petrobunus hebei sp. nov. holotype. 37. Penis, dorsal view. 38. Same, lateral view. 39. Distal part of penis (expanded), lateral view. 40. Same, lateral view. 41. Penis, dorsal view. 42. Same, lateral view. 43. Distal part of penis (expanded), lateral view. 44. Same, lateral view. 45. Same, lateral view (fully expanded). Ce, capsula externa; Ci, Capsula interna; DI, dorsal lobe; G, glans; Pb, pars basalis; Pd, pars distalis; S, stylus; VI, ventral lobe; VP, ventral plate. Scale bars: 0.25 mm