Psechrus vivax Bayer 2012, sp. nov.
Creators: name: Bayer, Steffen
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Araneae
Psechridae
Psechrus
Psechrus vivax

description: Psechrus vivax sp. nov.
Figs 50a–e, 51a–g, 85o, 88o, 91o
Type material: Holotype ♂ (SB 310), THAILAND: Trat Province: Koh Chang Island, Klong Plu School, N 12°03'25.5'', E 102°18'31.2'', 78 m, jungle stream, rocks/ rock wall besides stream; P. Jäger & S. Bayer leg. 01.XI.2009; SMF. Paratypes (3 ♂♂, 2♀♀, 4 s.a. ♀♀): 2 ♂ (SB 291–292), 3 s.a. ♀♀ (SB 308, 336, 366 [with fully developed epigyne underneath cuticula of subadult specimen]), same data as for holotype; SMF; 1 ♂ (SB 364), 1 ♀ (SB 293), 1 s.a. ♀ (SB 365), THAILAND: Trat Province: Koh Chang Island, Kheeri Phet Waterfall, N 12°00'27.6'', E 102°21'09.2'', 50–150 m, (secondary) jungle forest, between rocks, boulder and roots of trees; P. Jäger & S. Bayer leg. 02.XI.2009 (SB 293: 31.X.2009); SMF.
Etymology. The specific name refers to the durability of the type specimens. After collecting they were kept alive in small boxes and endured therein for more than five weeks (Latin “vivax” means “long-living, durable”); term (adverb) in apposition.
Diagnosis (see also diagnosis for himalayanus -group above). Males similar to P. jaegeri sp. nov. in having strongly curved embolus (E) with several ridges and an almost square course of sperm duct (Figs 48a–c, 50a–c). Distinguished by the E with continuous shape, its distal section (Fig. 50e) slightly broader than in P. jaegeri sp. nov. Moreover, tegulum (T) with distal half slightly broader than basal half (Fig. 50b). Females similar to P. jaegeri sp. nov. in having mushroom-like shape of median septum (MS) (Fig. 49a, 51a,f), very short copulatory ducts (CD) and compact spermatheca with their heads (SH) on top (Fig. 49b, 51b,g). Distinguished by the narrower anterior part of MS (ratio ‘anterior part / posterior part’ <2.2) (Fig. 51a,f) and the less compact spermathecae (Fig. 51b,g).
Description. Male (measurements of holotype first, those of male paratypes given as ranges in parentheses):
Body and eye measurements. Carapace length 6.4 (6.2–7.6), carapace width 4.6 (4.4–5.5), anterior width of carapace 2.4 (2.4–2.9), opisthosoma length 9.3 (8.7–10.5), opisthosoma width 2.6 (2.5–3.6). Eyes: AME 0.34 (0.33–0.38), ALE 0.41 (0.39–0.43), PME 0.40 (0.39–0.44), PLE 0.36 (0.37–0.44), AME–AME 0.22 (0.20–0.22), AME–ALE 0.04 (0.04–0.06), PME–PME 0.28 (0.22–0.29), PME–PLE 0.34 (0.33–0.38), AME–PME 0.62 (0.49–0.62), ALE–PLE 0.44 (0.42–0.45), clypeus height at AME 0.81 (0.79–0.95), clypeus height at ALE 0.68 (0.67–0.73).
Cheliceral furrow with three promarginal and four retromarginal teeth.
Measurements of palp and legs. Leg formula: 1423. Palp 8.2 (7.7–8.6) [3.0 (2.8–3.2), 1.3 (1.2–1.5), 1.2 (1.1–1.3), 2.7 (2.6–2.8)], I 57.1 (53.7–65.2) [14.7 (14.1–17.1), 3.1 (3.0–3.6), 15.6 (14.5–17.9), 16.6 (15.6–19.1), 7.1 (6.5–7.5)], II 44.8 (44.2–51.3) [12.1 (11.8–13.9), 2.8 (2.8–3.2), 11.7 (11.4–13.8), 12.6 (12.6–14.3), 5.6 (5.6–6.1)], III 31.4 (30.7–35.9) [8.9 (8.8–10.2), 2.2 (2.2–2.6), 7.8 (7.5–8.9), 8.5 (8.3–9.9), 4.0 (3.9–4.3)], IV 47.9 (46.3–53.9) [12.9 (12.5–14.9), 2.5 (2.4–2.9), 12.1 (11.7–14.0), 13.9 (13.5–15.2), 6.5 (6.2–6.9)].
Spination. Palp: 131 (131), 110{010} (110,010), 1101 (0000); legs: femur I 566 (566), II 566{556} (566,556) III 555 (555), IV 555 (555,556); patella I–IV 000; tibia I–II 3038 (3038), III 3136 (3136), IV 3136 (3136,3036); metatarsus I–IV 3035 (3035).
Palpal femur without modification (Fig. 50d).
Copulatory organ (see also diagnosis and general description for himalayanus -group). Conductor (C) narrow, distal section slightly broader (Fig. 50b). Tegulum extending slightly further apically than in P. jaegeri sp. nov. (Fig. 50c). Palpal tibia in lateral view short (Figs 50a,c). Cymbium dorsally without scopula.
Female:
Body and eye measurements. Carapace length 6.4, carapace width 4.3, anterior width of carapace 2.8, opisthosoma length 9.3, opisthosoma width 4.3. Eyes: AME 0.35, ALE 0.42, PME 0.44, PLE 0.42, AME–AME 0.23, AME–ALE 0.05, PME–PME 0.26, PME–PLE 0.33, AME–PME 0.55, ALE–PLE 0.44, clypeus height at AME 0.84, clypeus height at ALE 0.66.
Cheliceral furrow with three promarginal and four retromarginal teeth.
Measurements of palp and legs. Leg formula: 1423. Palp: 8.1 [2.8, 1.2, 1.5, 2.6]; Legs: I 44.5 [11.7, 3.0, 12.4, 11.7, 5.7], II 36.0 [9.9, 2.5, 9.7, 9.4, 4.5], III 25.0 [7.3, 2.1, 6.1, 6.3, 3.2], IV 36.9 [10.3, 2.4, 9.5, 9.8, 4.9].
Palpal claw with 14 teeth.
Spination. Palp: 131, 110, 1101, 1014; legs: femur I 666, II 566, III 555, IV 554; patella I–IV 000; tibia I– II 3038, III 2016, IV 3036; metatarsus I– III 3035, IV 3034.
Copulatory organ (see also diagnosis and general description of himalayanus -group). Spermathecal heads (Fig. 51b) longer than in P. jaegeri sp. nov. (but only two adult females examined). Median septum smooth and glossy (Fig. 88o). Slit sense organs and epigynal muscle sigilla outside epigynal field (Fig. 51a).
Primordial copulatory organ. Pre-epigyne: Similar to P. jaegeri sp. nov. in shape of pre-MS. The latter almost as long as broad and with curved anterior margins (Fig. 49d, 51d). Distinguished by the broader posterior part of pre-MS (Fig. 51d).
Pre-vulva: Similar to P. jaegeri sp. nov. Distinguished by the less voluminous pre-spermatheca and the slightly more extending pre-SH (Fig. 51e).
Colouration of male and female (see also description for himalayanus -group and Psechrus). Median bands on carapace slightly serrated. Lateral bands narrow (0.5–0.7 diameter of PME) and (slightly) serrated. Light longitudinal line ventrally on opisthosoma continuous and narrow. If measured centrally on opisthosoma, its width is less than the width of one half of the cribellum (ca. 0.3–0.5 of one half of the cribellum).
Variation of copulatory organs. Females: The two females examined show less variation. In SB 293 from Kheeri Phet the posterior part of MS is slightly narrower (Fig. 51f). This female also shows slightly narrower receptacula (Fig. 51g).
Distribution. Thailand (Fig. 98).
description: Published as part of Bayer, Steffen, 2012, The lace-sheet-weavers — a long story (Araneae: Psechridae: Psechrus), pp. 1-170 in Zootaxa 3379 (1) on pages 94-96, DOI: 10.11646/zootaxa.3379.1.1, http://zenodo.org/record/6039832