Ptocasius filiformus, Yang & Peng, 2023

Yang, Su-Fang & Peng, Xian-Jin, 2023, A review of the Ptocasius Simon, 1885 spiders of Gaoligong Mountains, China (Araneae: Salticidae), European Journal of Taxonomy 903 (1), pp. 1-61 : 16-20

Ptocasius filiformus sp. nov.

urn:lsid:zoobank.org:act:B3841DD1-531B-4A28-9F3E-F9F51A2C7B39

Figs 10–12 , 41

Diagnosis

The male of the new species resembles that of P. urbanii ( Żabka, 1981) ( Żabka 1981: figs 31–34) in having the similar tibial apophysis in male palp, but can be distinguished by: (1) genital bulb significantly longer than wide in ventral view ( Figs 10B , 12A ), while as long as wide in P. urbanii ( Żabka 1981: fig. 31); (2) tip of tibial apophysis reaching posterior half of genital bulb in ventral view ( Figs 10 B, 12A), while reaching anterior half of genital bulb in P. urbanii ( Żabka 1981: fig. 31); (3) genital lobe long and horny, outer margin of genital lobe overpasses outer margin of tibial apophysis in ventral view ( Figs 10B , 12A ), while short and conic, just slightly overpassing inner margin of tibial apophysis in P. urbanii ( Żabka 1981: fig. 31). The female of the new species resembles that of P. urbanii ( Żabka 1981: figs 25–26, 41) in having similar pockets in the epigynum, but can be distinguished by: (1) epigynum almost as long as wide in ventral view ( Figs 11B , 12D ), while distinctly longer than wide in P. urbanii ( Żabka 1981: fig. 25); (2) copulatory openings almost as long as pocket length in ventral view ( Figs 11B , 12D ), while almost two times as long as pocket length in P. urbanii ( Żabka 1981: fig. 25); (3) top margins of spermathecae below and away from copulatory openings in dorsal view ( Figs 11C , 12E ), while slightly above and close to copulatory openings in P. urbanii ( Żabka 1981: fig. 26).

Etymology

The specific name is derived from the combination of the Latin terms ‘ filum ’ (‘thread’) and ‘ forma ’ (‘shape’), referring to the filiform embolus, noun in apposition.

Type material

Holotype

CHINA • ♂; Yunnan Province, Longling County, Longjiang Township, Xiaoheishan Nature Reserve ( Guchengshan mountain ); 24º49′43″ N, 98º45′33″ E; 2010 m a.s.l.; 26 May 2005; Heng-mei Yan leg.; in the forest; HNU-GKJ026–1A.

Paratypes (3 ♀♀)

CHINA – Yunnan Province • 3 ♀♀; same collection data as for holotype; HNU-GKJ026– 1P.

Description

Male (holotype)

BODY AND HEAD. Total length 4.38. Prosoma 2.15 long, 1.77 wide. Opisthosoma 2.21 long, 1.23 wide. Clypeus high 0.09. Carapace ( Fig. 10A ) reddish brown, covered with white and brown hairs; carapace margin and eyes base black; ocular area covered with long thick dark brown hairs, anterior and lateral margins black with dense white hairs. Fovea sulciform, reddish brown. Cervical groove indistinct, radial groove dark brown. Eye diameters and interdistances: AME 0.49, ALE 0.23, PLE 0.29, PME 0.08, AERW 1.12, PERW 1.22, EL 1.08. Sternum scutiform, yellowish brown, covered with thin brown hairs; marginal areas with long brown hairs. Clypeus dark brown, sparsely covered with long brown hairs. Endites and labium yellowish brown, sparsely covered with long brown hairs; distal area light brown, densely covered with grayish hairs.

CHELICERAE ( Fig. 12C ). Yellowish brown, covered with long thick brown hairs, two promarginal teeth and one retromarginal denticle.

LEGS. Light yellow, covered with thick brown hairs, bearing numerous short spines. Tibiae I and II with three pairs of long ventral spines, metatarsi I and II with two pairs of ventral spines.

LEG MEASUREMENTS. I = 4.97 (1.50, 1.98, 0.84, 0.65), II = 4.14 (1.28, 1.60, 0.68, 0.58), III = 4.51 (1.34, 1.58, 1.11, 0.48), IV = 4.77 (1.46, 1.63, 1.16, 0.52). Leg formula: I–IV–III–II.

ABDOMEN ( Fig. 10A ). Elongated oval, dorsum light yellow, covered with thick white hairs and black stripes, sparsely covered with long brown hairs; each side with a wide longitudinal band; the posterior inner area with three pairs of inclined markings; the median area with black arc-shaped markings; ventral yellowish white, covered with white hairs; the median area with a black longitudinal band and irregular black inclined markings. Spinnerets brown, densely covered with long brown hairs.

PALP ( Figs 10B–C , 12A–B ). Longer than wide; embolus slender, originates at about 8:00 o’clock position; genital bulb almost rectangular, genital lobe comma-shaped; the tip of tibial apophysis only extending to the posterior half of genital bulb in ventral view.

Female (paratypes)

BODY AND HEAD. Total length 4.79. Prosoma 2.09 long, 1.46 wide. Opisthosoma 2.82 long, 1.66 wide. Clypeus high 0.08.Carapace ( Fig. 11A ) reddish brown, covered with white and brown hairs; base carapace margin and eyes base black; ocular area covered with long dark brown hairs, anterior and lateral margins black covered with dense white hairs. Fovea sulciform, reddish brown. Cervical groove indistinct, radial groove reddish brown. Eye diameters and interdistances: AME 0.43, ALE 0.22, PME 0.07, PLE 0.25, AERW 0.95, PERW 1.10, EL 0.88. Sternum scutiform, yellowish brown, covered with brown hairs. Clypeus dark brown, distal area covered with brown hairs. Endites and labium reddish brown, sparsely covered with long brown hairs; distal area light brown, densely covered with grayish hairs.

CHELICERAE ( Fig. 12F ). Yellowish brown, sparsely covered with long brown hairs, two promarginal teeth and one retromarginal denticle.

LEGS. Yellowish brown, densely covered with white hairs, bearing numerous short spines. Tibiae I and II with three pairs of long ventral spines, metatarsi I and II with two pairs of ventral spines.

LEG MEASUREMENTS. I = 3.07 (1.00, 1.18, 0.51, 0.38), II = 3.27 (1.01, 1.32, 0.53, 0.41), III = 3.54 (1.16, 1.22, 0.74, 0.42), IV = 3.98 (1.22, 1.45, 0.80, 0.51). Leg formula: IV–III–II–I.

ABDOMEN ( Fig. 11A ). Oval, dorsum yellow, covered with brown hairs and black stripe; inner area with four inclined markings; distal area covered with long brown hairs; each side with a wide longitudinal band; the posterior median area with black herring bones; ventral light yellow, the median area with a brown longitudinal band. Spinnerets brown, densely covered with long brown hairs.

EPIGYNUM ( Figs 11B–C , 12D–E ). As long as wide; the pockets below and relatively away from copulatory openings, interdistance of pockets wider than interdistance of copulatory openings; copulatory openings small, almost ()-shaped; copulatory ducts S-shaped; spermathecae tube-shaped, close to each other, heads touching.

Distribution

China (Yunnan Province, Fig. 41 ).

Figures

Fig. 10. Ptocasius filiformus sp. nov., holotype, ♂ (HNU-GKJ026–1A). A. Body, dorsal view. B. Palp, ventral view. C. Palp, retrolateral view. Scale bars: A = 0.5 mm; B–C = 0.1 mm.

Fig. 11. Ptocasius filiformus sp. nov., paratype, ♀ (HNU-GKJ026–1P). A. Body, dorsal view. B. Epigynum, ventral view. C. Vulva, dorsal view. Scale bars: A = 0.5 mm; B–C = 0.1 mm.

Fig. 12. Ptocasius filiformus sp. nov. A–C. Holotype, ♂ (HNU-GKJ026–1A). D–F. Paratype, ♀(HNU-GKJ026–1P). A. Palp, ventral view. B. Palp, retrolateral view. C. Chelicerae, posterior view. D. Epigynum, ventral view. E. Vulva, dorsal view. F. Chelicerae, posterior view. Scale bars = 0.1 mm.

Fig. 41. Distribution records of the species: P. angulatus sp. nov. (▲), P. filiformus sp. nov. (•) and P. robustus sp. nov. (▇).

Fig. 1.Ptocasius angulatus sp. nov., holotype, ♀ (HNU-98–EP–1A). A. Body, dorsal view.B. Epigynum, ventral view. C. Vulva, dorsal view. Scale bars: A = 0.5 mm; B–C = 0.1 mm.