Ptocasius circulus sp. nov.

urn:lsid:zoobank.org:act: 56D8C9A4-03B4-4646-80DC-49E5A3D730A2

Figs 3–4, 42

Diagnosis

The new species resembles P. strupifer Simon, 1901 (Peng 2020: fig. 275f) in having the similar outline of copulatory openings and the position of pockets, but can be distinguished by: spermathecae relatively well folded, complicated in dorsal view (Figs 3C, 4B), while globular in P. strupifer (Peng 2020: fig. 275g).

Etymology

The specific name is derived from the Latin noun ‘ circulus ’ (‘circle’) in apposition, referring to the circular outline of the atrium.

Type material

Holotype

CHINA • ♀; Yunnan Province, 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–1.

Paratype (1 ♀)

CHINA – Yunnan Province • 1 ♀; 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-00–GD–1 .

Description

Female (holotype)

BODY AND HEAD. Total length 6.00. Prosoma 2.50 long, 1.85 wide. Opisthosoma 3.50 long, 2.20 wide. Clypeus height 0.10. Carapace (Fig. 3A) light brown; carapace margin and eye base black; ocular area dark brown, lateral margins black sparsely with long brown hairs. Fovea reddish brown, cervical and radial groove black, distinct. Eye diameter and interdistances: AME 0.53, ALE 0.30, PLE 0.30, AERW 1.70, PERW 1.65, EL 1.10. Sternum scutiform, covered with short brown hairs; the median area slightly bulged, yellowish brown, with dark brown margin. Clypeus dark brown, between sides and AMEs with three clusters long dark brown hairs; promargin with row of long hairs. Endites and labium brown, distal area light brown, covered with grayish black hairs.

CHELICERAE (Fig. 4C). Dark brown, distal area covered with long brown hairs, two promarginal teeth and one retromarginal denticle.

LEGS. Grayish black with black annuli, densely covered with grayish black hairs, bearing long and strong spines. 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 = 4.35 (1.35, 1.70, 0.70, 0.60), II = 4.00 (1.30, 1.50, 0.60, 0.60), III = 4.80 (1.45, 1.70, 0.90, 0.75), IV = 5.35 (1.60, 1.85, 1.20, 0.70). Leg formula: IV–III–I–II.

ABDOMEN (Fig. 3A). Oval, dorsum long oval, light yellow, each side with a wide grayish black longitudinal band, the marginal area with a light incision; the posterior portion with five light markings, mid-dorsally with two pairs of sigillae; ventral light yellow, the median area with a grayish black longitudinal band, sides with irregular grayish black markings and twills. Spinnerets dark brown.

EPIGYNUM (Figs 3B–C, 4A–B).Almost as long as wide; the pockets triangular, almost touching copulatory openings; epigynum with a transverse W-shaped band between connecting the bases of copulatory openings; atrium outline almost circular; spermathecae folded, much complicated.

Male

Unknown.

Distribution

China (Yunnan Province, Fig. 42).