Psechrus vivax, Bayer, 2012

Bayer, Steffen, 2012, The lace-sheet-weavers — a long story (Araneae: Psechridae: Psechrus), Zootaxa 3379 (1), pp. 1-170 : 94-96

publication ID	https://doi.org/ 10.11646/zootaxa.3379.1.1
DOI	https://doi.org/10.5281/zenodo.6303176
persistent identifier	https://treatment.plazi.org/id/D0272654-FFDD-581C-FF20-2C09FDE042EA
treatment provided by	Felipe
scientific name	Psechrus vivax
status	sp. nov.

Treatment

Psechrus vivax View in CoL sp. nov.

Figs 50a–e View FIGURES 50 , 51a–g View FIGURES 51 , 85o View FIGURES 85 , 88o View FIGURES 88 , 91o View FIGURES 91

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 GoogleMaps . 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 ) GoogleMaps , 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 GoogleMaps .

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 View FIGURES 48 , 50a–c View FIGURES 50 ). Distinguished by the E with continuous shape, its distal section ( Fig. 50e View FIGURES 50 ) slightly broader than in P. jaegeri sp. nov. Moreover, tegulum (T) with distal half slightly broader than basal half ( Fig. 50b View FIGURES 50 ). Females similar to P. jaegeri sp. nov. in having mushroom-like shape of median septum (MS) ( Fig. 49a View FIGURES 49 , 51a,f View FIGURES 51 ), very short copulatory ducts (CD) and compact spermatheca with their heads (SH) on top ( Fig. 49b View FIGURES 49 , 51b,g View FIGURES 51 ). Distinguished by the narrower anterior part of MS (ratio ‘anterior part / posterior part’ <2.2) ( Fig. 51a,f View FIGURES 51 ) and the less compact spermathecae ( Fig. 51b,g View FIGURES 51 ).

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 View FIGURES 50 ).

Copulatory organ (see also diagnosis and general description for himalayanus -group). Conductor (C) narrow, distal section slightly broader ( Fig. 50b View FIGURES 50 ). Tegulum extending slightly further apically than in P. jaegeri sp. nov. ( Fig. 50c View FIGURES 50 ). Palpal tibia in lateral view short ( Figs 50a,c View FIGURES 50 ). 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 View FIGURES 51 ) longer than in P. jaegeri sp. nov. (but only two adult females examined). Median septum smooth and glossy ( Fig. 88o View FIGURES 88 ). Slit sense organs and epigynal muscle sigilla outside epigynal field ( Fig. 51a View FIGURES 51 ).

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 View FIGURES 49 , 51d View FIGURES 51 ). Distinguished by the broader posterior part of pre-MS ( Fig. 51d View FIGURES 51 ).

Pre-vulva: Similar to P. jaegeri sp. nov. Distinguished by the less voluminous pre-spermatheca and the slightly more extending pre-SH ( Fig. 51e View FIGURES 51 ).

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 View FIGURES 51 ). This female also shows slightly narrower receptacula ( Fig. 51g View FIGURES 51 ).

Distribution. Thailand ( Fig. 98 View FIGURE 98 ).