Ptocasius geminus, Yang & Peng, 2023

Ptocasius geminus sp. nov.

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Figs 15–17 View Fig View Fig View Fig , 44 View Fig

Diagnosis

The male of the new species resembles that of P. falcatus ( Zhu et al., 2005) ( Zhu et al. 2005: fig. 13d–e) in having a similar morphology of the male palp, but can be distinguished by: (1) genital bulb distinctly longer than wide in ventral view ( Figs 15B View Fig , 17A View Fig ), while almost as long as wide in P. falcatus ( Zhu et al. 2005: fig. 13d); (2) genital lobe thumb-shaped in ventral view ( Figs 15B View Fig , 17A View Fig ), while somewhat rectangular in P. falcatus ( Zhu et al. 2005: fig. 13d); (3) tibial apophysis knife-shaped in retrolateral view ( Figs 15C View Fig , 17B View Fig ), while finger-shaped in P. falcatus ( Zhu et al. 2005: fig. 13e). The female of the new species resembles that of P. falcatus ( Zhu et al. 2005: fig. 13a–c) in having a similar morphology of the epigynum, but can be distinguished by: (1) top of pockets below posterior margin of copulatory openings in ventral view ( Figs 16B View Fig , 17D View Fig ), while anterior margin present between copulatory openings in P. falcatus ( Zhu et al. 2005: fig. 13b); (2) posterior margin of pockets two times as wide as long in ventral view ( Figs 16B View Fig , 17D View Fig ), while as long as wide in P. falcatus ( Zhu et al. 2005: fig. 13b).

Etymology

The specific name is derived from the Latin adjective ‘ geminus ’ (‘twin-born’), referring to the form of epigynum pockets.

Type material

Holotype

CHINA • ♂; Yunnan Province, Nujiang Prefecture, Gongshan County, Danzhu , 15.7–16.0 km Southwest of Gongshan ; 27°37′37″ N, 98°35′31″ E to 27°37′19″ N, 98°35′14″ E; 2800–3425 m a.s.l.; 2 Jul. 2000; Heng-mei Yan, David Kavanaugh, Charles Griswold, Hong-bin Liang, Darrell Ubick and Da-zhi Dong leg.; HNU-00–GDS–2A. GoogleMaps

Paratypes (14 ♁♁, 18 ♀♀)

CHINA – Yunnan Province • 4 ♀♀; same collection data as for holotype; HNU-00–GDS–2P GoogleMaps • 10 ♂♂, 9 ♀♀; Nujiang Prefecture, Nujiang State Nature Reserve, No. 12 bridge Camp area , 16.3 km West of Gongshan; 27°42′54″ N, 98°30′08″ E; 2775 m a.s.l.; 15–17 Jul. 2000; Heng-mei Yan, David Kavanaugh, Charles Griswold, Hong-bin Liang, Darrell Ubick and Da-zhi Dong leg.; HNU-Yan000715 GoogleMaps • 1 ♂; Nujiang Prefecture, Gongshan County, Nujiang State Nature Reserve , Qiqi , 9.9 km West of Gongshan; 27°42′55″ N, 98°33′55″ E; 2000 m a.s.l.; 9–14 Jul. 2000; Heng-mei Yan, David Kavanaugh, Charles Griswold, Hong-bin Liang, Darrell Ubick and Da-zhi Dong leg.; HNU-00–QF–5 GoogleMaps • 3 ♂♂, 5 ♀♀; Nujiang Prefecture, Gongshan County, Danzhu , 13.5 km Southwest of Gongshan; 27°37′50″ N, 98°37′14″ E; 2700 m a.s.l.; 30 Jun.–5 Jul. 2000; David Kavanaugh, Charles Griswold, Hong-bin Liang, Darrell Ubick, Heng-mei Yan and Da-zhi Dong leg.; HNU-Yan000730 GoogleMaps .

Description

Male ( holotype)

BODY AND HEAD. Total length 4.60. Prosoma 1.80 long, 1.40 wide. Opisthosoma 2.80 long, 1.30 wide. Clypeus height 0.10. Carapace ( Fig. 15A View Fig ) dark brown, carapace margin and eyes base black, anterior and lateral margins black; anterior and lateral margins of ocular area black with dense white hairs; PLE followed by two small slightly colored circles. Fovea thin, reddish brown, radial groove black, line-shaped. Eye diameter and interdistances: AME 0.40, ALE 0.20, PLE 0.20, AERW 1.20, PERW 1.10, EL 0.80. Sternum inverse pear-shaped, highly bulged, densely covered with fine brown hairs; yellowish brown, margin black. Clypeus dark brown, sparsely covered with long brown hairs; promargin black, sides light brown. Endites and labium brown, distal area covered with light grayish black hairs.

CHELICERAE ( Fig. 17C View Fig ). Brown, anterolateral area black, two large promarginal teeth and one small retromarginal denticle.

LEGS. Light brown to brown, with black markings or annuli; spines short. Tibiae I and II with three pairs of long ventral spines, metatarsi I and II with two pairs of ventral spines.

LEG MEASUREMENTS. I = 3.30 (1.00, 1.30, 0.50, 0.50), II = 2.95 (0.95, 1.10, 0.45, 0.45), III = 3.35 (1.00, 1.10, 0.70, 0.50), IV = 3.70 (1.20, 1.20, 0.80, 0.50). Leg formula: IV–III–I–II.

ABDOMEN ( Fig. 15A View Fig ). Oval, dorsum anterior margin black; cardiac marking bar-shaped, grayish black, with two pairs of sigillae; the posterior median with two large black herring bones; sides with some irregular black twills, ventral light yellow, the median area with small black spots, sides with many black twills; the posterior area with a big black marking. Spinnerets dark brown.

PALP ( Figs 15B–C View Fig , 17A–B View Fig ). Longer than wide; embolus originates at about 8:00 o’clock position; genital bulb with a membranous structure; genital lobe thumb-shaped in ventral view; tibial apophysis knife-shaped.

Female ( paratypes)

BODY AND HEAD. Total length 5.60. Prosoma 2.10 long, 1.60 wide. Opisthosoma 3.50 long, 2.40 wide. Eye diameter and interdistances: AME 0.40, ALE 0.25, PLE 0.25, AER 1.35, PER 1.30, EFL 0.90. Tibiae I and II with three pairs of long ventral spines, metatarsi I and II with two pairs of long ventral spines.

LEG MEASUREMENTS. I = 3.40 (1.10, 1.30, 0.50, 0.50), II = 3.10 (1.00, 1.20, 0.50, 0.40), III = 3.80 (1.20, 1.30, 0.70, 0.60), IV = 4.50 (1.40, 1.50, 1.00, 0.50). Leg formula: IV–III–I–II.

ABDOMEN ( Fig. 16A View Fig ). Mid-ventrally with a grayish black longitudinal band. Markings and other morphological features the same as in male.

EPIGYNUM ( Figs 16B–C View Fig , 17D–E View Fig ). Almost as long as wide; the pockets almost touching, present below the copulatory openings; copulatory openings almost transverse; copulatory ducts cylindrical; spermathecae spiral, close to each other.

Distribution

China ( Yunnan Province, Fig. 44 View Fig ).