Systaria bifida, Dankittipakul, Pakawin & Singtripop, Tippawan, 2011

Dankittipakul, Pakawin & Singtripop, Tippawan, 2011, Seven new species of Systaria Simon, 1897 from Southeast Asia (Araneae, Clubionidae, Systariinae), Zootaxa 2905, pp. 16-32 : 24-26

Systaria bifida sp. nov.

Figs 20–25

Type material. Holotype: 3, THAILAND: Narathiwat Province: Waeng Dao District, Hala-Bala Wildlife Sanctuary, Sirinthorn Waterfalls, 200 m, evergreen rainforest, 8 January 1999, leg. P.J. Schwendinger ( MHNG, Sys-04).

Paratypes: 1Ƥ, same data as holotype ( MHNG). THAILAND: Phang Nga Province: 13, Khao Lak National Park, Tone Chong Fa Waterfall, 100-300 m, Winkler extraction in primary moist forest with secondary spot, 15 January 1998, leg. A. Schulz & K. Vock, ( MHNG, AS-T- 3, Sys-06). MYANMAR: Taninthayi Division: 1Ƥ, Taninthayi Kyun [= Pulo Ru, Ko Song], 9º56'N 98º32'E, 60 m, old secondary forest, 4 July 2007, leg. P.J. Schwendinger ( MHNG, TH- 07/04, Syst-07).

Diagnosis. Males of S. bifida sp. nov. can be recognized by a bifid ventral process on the RTA ( Figs 20–23 ). Females resemble those of S. decidua sp. nov. in having the similar shape of anterior bursae but can be distinguished by the lack of a median septum on the epigynal atrium ( Figs 14 vs. 25).

Etymology. The specific epithet is an adjective derived from Latin (bifidus, -a, -um), referring to the shape of a ventral process on the RTA of the male palp.

Description. Male (holotype): Total length 7.88. Prosoma 3.58 long, 2.46 wide. Opisthosoma 4.30 long, 2.12 wide. Leg formula: 4123; I 11.36 (2.94, 1.60, 2.86, 2.54, 1.42); II 9.60 (2.76, 1.32, 2.60, 1.84, 1.08); III 8.44 (2.28, 0.86, 1.92, 2.30, 1.08); IV 12.16 (3.42, 1.12, 3.16, 3.30, 1.16). Spination. Femora I d1-1-1, p1-1-1, r1-0-1; II d1-1- 1, p1-0-2, r0-1-0; III d1-1-1, p0-1-1, r1-1-1; IV d1-1-1, p0-1-1, r1-2. Tibiae: I v2-2 -2; II v2-2 -2; III d0-1-0, p0-1-1, r2-2-2, v2-2 -2; IV d0-1-0, p1-1-0, r1-1-0, v2-2 -2. Metatarsi: I v1 -0-0; II v1-2; III p1-1-2, r1-1-2, v1-1 -1; IV p1-1-1, r2-2-2, v1-1 -1. Eye size and interdistances: AME 0.14, ALE 0.10, PME 0.10, PLE 0.08; AME–AME 0.18, AME– ALE 0.16, PME–PME 0.24, PME–PLE 0.16, ALE–PLE 0.12; MOA 0.30 long, anterior width 0.32, posterior width 0.30.

Palp ( Figs 20–23 ). Ventral surface of tibia with distinct distal swelling. RTA broad in lateral view, provided with bifid ventral process ( Figs 21–23 ) and blunt dorsal process ( Fig. 21 ). Cymbial fold partially membranous. Cymbial tubercle triangular, sharply pointed. Embolus triangular; embolic base membranous; distal part of embolus filiform, elongated. Conductor membranous, with triangular apical flange directed anteriad and rostrate retrolateral extension directed retrolaterad.

Female (paratype, MHNG, Sys-04): Total length 10.54. Prosoma 4.92 long, 3.46 wide. Opisthosoma 5.82 long, 3.18 wide. Leg formula: 4123; I 9.50 (2.72, 1.44, 2.62, 1.74, 0.98); II 8.90 (2.66, 1.32, 2.34, 1.68, 0.90); III 8.50 (2.94, 0.92, 1.82, 1.98, 0.84); IV 12.82 (3.62, 1.36, 2.88, 3.32, 1.64). Spination. Femora: I d1-1-1, p1-0-1, r0-1-1; II d1-1-1, p0-1-1, r0-1-2; III d1-1-1, p0-1-1, r1-1-1; IV d1-1-1, p1-1-1, r0-1-1. Tibiae: I v2-2 -0; II v0-2-0; III p1-0-2, r1-1-0, v2-2 -2; IV p1-1-0, r1-1-0, v2-2 -2. Metatarsi: II v1-1 -0; III p1-1-2, r1-1-2, v2 -0-2; IV p1-1-2, r1-1-1, v2-2 -2. Eye size and interdistances: AME 0.16, ALE 0.12, PME 0.12, PLE 0.12; AME–AME 0.18, AME–ALE 0.16, PME–PME 0.24, PME–PLE 0.18, ALE–PLE 0.14; MOA 0.26 long, anterior width 0.36, posterior width 0.36.

Genitalia ( Figs 24–25 ). Epigynal atrium shallow, with clearly elevated anterior ridge. Copulatory orifices situated medially. Anterior bursae sclerotized, elongated, widest in the middle, distinctly narrowed anteriorly and posteriorly. Insemination ducts with mating plugs. Spermathecae spherical. Fertilization ducts subulated.

Natural history. Types of S. bifida sp. nov. were collected from humid habitats in lowland forests near the seashore.

Distribution. Southern Thailand and Myanmar (Fig. 43).

Figures

FIGURES 20 – 25. Systaria bifida sp. nov., holotype male (20 – 23) and paratype female (24 – 25). 20 – 21 Left male palp (20 ventral, 21 retrolateral); 22 – 23 Palpal tibia (22 proventral, 23 dorsal); 24 Epigyne, ventral; 25 Vulva, dorsal. Scale lines = 0.1 mm.

FIGURES 9 – 14. Systaria decidua sp. nov., holotype male (9 – 11) and paratype female (12 – 14). 9 – 11 Left male palp (9 ventral, 10 retrolateral, 11 dorsal); 12 – 13 Epigyne, ventral; 14 Vulva, dorsal. Scale lines = 0.1 mm.