Asiafroneta pallida, Tanasevitch, 2020

Tanasevitch, Andrei V., 2020, Asiafroneta, a new genus of the spider subfamily Mynogleninae, with two new species from Borneo, East Malaysia (Araneae: Linyphiidae), Raffles Bulletin of Zoology 68, pp. 56-61 : 57-58

Asiafroneta pallida , new species

( Figs. 1–5 , 11, 12 , 16, 17 )

Holotype. Male ( MHNG), EAST MALAYSIA, Sabah (West Coast Residency), Kinabalu Park , Mt Kinabalu , 2590 m a.s.l., wet ravine below Layang Layang, mist forest, sifting wet plant debris, 1 May 1987, coll. D. Burckhardt and I. Löbl [10a].

Paratypes. 1 male, 4 females ( MHNG), together with the holotype; 1 male, 1 female ( MHNG), EAST MALAYSIA, Sarawak, Santubong, 32 km N of Kuching, 0–50 m a.s.l., under bark of fallen trees along edge of secondary mixed dipterocarp forest, 28–29 May 1994, coll. I. Löbl and D. Burckhardt [13a].

Etymology. The specific epithet is a Latin adjective referring to the pale body in the new species.

Description. Male holotype. Total length 1.95. Carapace unmodified ( Fig. 1 ), 1.05 long, 0.78 wide, pale greyish brown, with indistinct grey radial stripes. Clypeus below each anterior lateral eye with a narrow and elongated groove (sub-ocular sulci), as in Fig. 4 . Chelicerae 0.38 long, anterior margin of fang groove with three strong teeth, mastidion absent. Legs pale greyish brown to yellow. Leg I 3.16 long (0.88 + 0.28 + 0.75 + 0.75 + 0.50), IV 3.27 long (0.88 + 0.28 + 0.75 + 0.78 + 0.58). Chaetotaxy: FeI: 0-1-0-0, II–IV: 0-0-0-0; TiI: 2-1- 0-0, II–III: 2-0-0-0, IV: 1-1-0-0. Metatarsi unarmed. Length of spines 1.5–3 diameters of corresponding leg segment. TmI 0.65. Metatarsi IV without trichobothrium. Palp ( Figs. 11, 12 ): Patella with a stout dorso-apical spine. Tibia long, subequal in length to cymbium. Cymbium narrow, bearing three macrosetae distally. Paracymbium simple, small, flat, L-shaped. Distal suprategular apophysis relatively short and thin, needle-shaped. Tegulum with a conical extention distally. Median membrane poorly visible, simply a short and membraneous process. Embolus relatively short and narrow, radix small, oblong-oval. Abdomen ( Fig. 1 ) 1.05 long, 0.60 wide, grey.

Female. Total length 1.90. Carapace unmodified ( Fig. 2 ), 0.95 long, 0.73 wide, pale greyish brown. Clypeus below each anterior lateral eye with a narrow and elongated groove (sub-ocular sulci), as in Fig. 5 . Chelicerae 0.40 long, anterior margin with three strong teeth, mastidion absent. Legs pale brown to yellow. Leg I 2.93 long (0.90 + 0.30 + 0.65 + 0.60 + 0.48), IV 2.98 long (0.85 + 0.25 + 0.70 + 0.65 + 0.53). TmI 0.65. Metatarsi IV without trichobothrium. Abdomen ( Fig. 2 ) 1.05 long, 0.70 wide, grey. Epigyne and vulva ( Figs. 3 , 16, 17 ): Epigyne small, anterior wall (= ventral plate, auct.) with a notch, posterior median plate (= dorsal plate, auct.) with a rudimentary parmula (= scapus, auct.), a pit present. Receptacles sub-spherical, median ducts globularly expanded distally, almost contiguous. Body colouration and chaetotaxy as in male.

Note. The female paratype from Santubong has two dorsal spines on TiIV vs. only one in other paratypes.

Taxonomic remarks. The new species is very similar to the following new species from Borneo, see below. By the structure of the genitalia, namely, the distal suprategular apophysis, radix and embolus, A. pallida , new species, resembles Parafroneta marrineri ( Hogg, 1909) and P. minuta Blest, 1979 , both known from New Zealand. The new species differs well in its significantly smaller size (about 2 mm vs. 6.50 in P. marrineri , 2.80 in P. minuta ), a deeper notch in the anterior wall of the epigyne, as well as by the median ducts placed more closely to each other.

Distribution. Known only from Sabah and Sarawak (East Malaysia) on Borneo Island.

Figures

Figs. 1–10. Photographs of Asiafroneta pallida, new species, male holotype (1, 4), female paratype from Layang Layang (2, 3, 5); A. atrata, new species, male holotype (6, 9) and female paratype (7, 8, 10). 1, 2, 6, 7, body, dorsal view; 3, 8, posterior part of body, ventral view; 4, 5, 9, 10, prosoma, frontal view.

Figs. 11–15. Details of male palp structure of Asiafroneta pallida, new species, male holotype (11, 12) and A. atrata, new species, male holotype (13–15). 11, 13, right palp, retrolateral view; 12, 14, right palp, prolateral view; 15, embolic division, mesal view, not to scale.

Figs. 16–20. Epigyne and vulva structure of Asiafroneta pallida, new species, female paratype from Layang Layang (16, 17) and A. atrata, new species, female paratype (18–20). 16, 18, epigyne, ventral view; 17, 19, 20, vulva, dorsal view, different aspects.