Psechrus tauricornis, Bayer, 2012

Bayer, Steffen, 2012, The lace-sheet-weavers — a long story (Araneae: Psechridae: Psechrus), Zootaxa 3379 (1), pp. 1-170 : 135-137

publication ID	https://doi.org/ 10.11646/zootaxa.3379.1.1
DOI	https://doi.org/10.5281/zenodo.6303188
persistent identifier	https://treatment.plazi.org/id/D0272654-FF06-58CB-FF20-2ABAFD9E43BA
treatment provided by	Felipe
scientific name	Psechrus tauricornis
status	sp. nov.

Treatment

Psechrus tauricornis View in CoL sp. nov.

Figs 75a–g View FIGURES 75 , 81j View FIGURES 81 , 82g,k View FIGURES 82 , 89p View FIGURES 89 , 92p View FIGURES 92

Psechrus torvus View in CoL — Simon 1905b: 167 (material from Kandy, misidentified). Levi 1982: 122, figs 16–28, ad part, figs 23–28 misidentified (figs 25–26: illustration of ♀).

Type material. Holotype ♀ ( SB 129 ), SRI LANKA: Central Province: Kandy , near waterworks, ca. N 07°17', E 80°38', ca. 600 m, forest, along vertical walls of stream; C.L. Deeleman & P.R. Deeleman leg. 11.VIII.1981; Deeleman Coll. in RMNH GoogleMaps ; Paratypes: 1 ♀ ( SB 849 ), 1 s.a. ♀ ( SB 850 ), SRI LANKA: Central Province: Nawalapitiya , ca. N 07°02', E 80°32', 915 m, road-banks; W.R. Sherriffs leg. 1914–1918, collected between February and May; W.R. Sherriffs det. P. torvus 1919 ; Tilg. 20-11-1960; ZMUC 12814 GoogleMaps .

Additional material examined (3 ♀♀, 1 s.a. ♀, 6 juvs). SRI LANKA (‘Ceylan’): Possibly Kandy; E. Simon leg. before 1892; Simon det. P. torvus ; Simon-Coll. No. 499; 1♀ ( SB 633 ), MNHN AR170/5; 1 ♀ ( SB 634 ), MNHN AR170/4. GoogleMaps SRI LANKA: Central Province: Kandy, near waterworks, ca. N 07°17', E 80°38', ca. 600 m, forest, along vertical walls of stream; C.L. Deeleman & P.R. Deeleman leg. 11.VIII.1981; 6 juvs ( SB 851–856 ), Deeleman Coll. in RMNH. GoogleMaps SRI LANKA: Central Province: Vakarawatte (near Kandy); Pagel leg. 1973; ‘Eingang’ (acquisition): 15.I.1974, 1 s.a. ♀ ( SB 515 ), NHMW. GoogleMaps SRI LANKA: Southern Province: Hiniduma, Kanneliya Forest Reserve (‘Kaneliya’), ca. N 06°17', E 80°20', ca. 150 m; R.R. Jackson leg. 09.I.1982, Zoo. Dept. Univ. Cant. NZ; |SL 25|; D.P. Wijesinghe det. P. torvus 1983 ; 1 ♀ ( SB 261 ), NHM GoogleMaps .

Additional doubtful material examined. SRI LANKA: Sabaragamuwa Province: Sinharaja Nature Reserve, near Pitadeniya , N 6°21'40.19'', E 80°29'03.61'', ca. 300 m, primary rainforest, slope at pathside; V. Hartmann leg. 16.I.2011; 1 juv. ( SB 885 ), SMF GoogleMaps .

Etymology. The specific name refers to the shape of the epigynal median septum of the female type specimens resembling a bull head in frontal view (Ancient Greek “tauros” means “bull, buffalo”; latin “cornu” means “horn”); adjective.

Diagnosis (see also diagnosis for torvus -group above). Females with branches of tegimentum (TM) distally pointed and resembling the horns of a bull ( Figs 75a,e View FIGURES 75 , 89p View FIGURES 89 ). Copulatory duct (CD) with small loops being more or less equal in size ( Figs 75b,d View FIGURES 75 , 92p View FIGURES 92 ).

Description. Male: unknown.

Female (Measurements of holotype first, those of other females as range in parentheses):

Body and eye measurements. Carapace length 7.8 (6.1–8.8), carapace width 5.1 (4.3–5.5), anterior width of carapace 3.5 (2.8–4.0), opisthosoma length 10.4 (9.1–10.3), opisthosoma width 6.2 (4.9–3.9). Eyes: AME 0.39 (0.32–0.40), ALE 0.42 (0.38–0.51), PME 0.43 (0.39–0.44), PLE 0.44 (0.39–0.45), AME–AME 0.24 (0.19–0.28), AME–ALE 0.08 (0.03–0.15), PME–PME 0.28 (0.25–0.28), PME–PLE 0.37 (0.33–0.43), AME–PME 0.62 (0.57–0.68), ALE–PLE 0.52 (0.46–0.53), clypeus height at AME 1.14 (1.03–1.53), clypeus height at ALE 0.98 (0.87–1.23).

Cheliceral furrow with three promarginal and four retromarginal teeth.

Measurements of palp and legs. Leg formula: 1423. Palp: 9.6 (8.2–11.0) [3.2 (2.7–4.0), 1.4 (1.2–1.6), 2.0 (1.7–2.1), 3.0 (2.6–3.3)]; Legs: I 46.0 (41.3–56.1) [12.4 (11.0–14.9), 3.3 (2.6–3.8), 12.7 (11.2–15.4), 11.8 (11.1–15.5), 5.8 (5.4–6.5)], II 37.3 (33.3–43.3) [10.3 (9.2–12.2), 3.0 (2.4–3.4), 9.7 (8.8–10.8), 9.6 (8.6–11.6), 4.7 (4.3–5.3)], III 26.9 (23.2–28.7) [8.1 (6.8–8.7), 2.3 (1.9–2.5), 6.5 (5.5–6.6), 6.6 (5.9–7.4), 3.4 (3.1–3.5)], IV 38.5 (34.8–44.0) [10.8 (9.8–12.5), 2.7 (2.1–2.8), 9.7 (8.8–10.8), 10.0 (9.2–12.1), 5.3 (4.9–5.8)].

Palpal claw with 14 (13–15) teeth.

Spination. Palp: 121{141} (131,141,142), 110 (110), 1101 (1101), 1014 (1014); legs: femur I 556 (566,676,757), II 556 (546,657,855) III 545 (545,546), IV 554 (555,654,554); patella I–IV 000 (000); tibia I– II 3038 (3038,30310), III 2124 (2124,2134,3134), IV 3134 (3136); metatarsus I 3037 (3037,3038,3047), II 3037 (3037), III 3035 (3035), IV 3036 (3037,3035,3036).

Copulatory organ (see also diagnosis and general description of torvus -group). Distal endings of the branches of TM pointing anterio-medially ( Fig. 75a View FIGURES 75 ). Epigyne with many wrinkles and ridges surrounding MS and mostly without (distinct) epigynal field (EF). Copulatory ducts (CD) just a bit larger than receptacula. Spermathecal heads arising anterio-medial on receptacula ( Fig. 75b View FIGURES 75 ).

Primordial copulatory organ. Pre-epigyne: Pre-septum (pre-MS) with one posterior transversal edge. Anterior margins of pre-MS visible as two small longitudinal edges ( Fig. 75f View FIGURES 75 ) below anterior margins of pre-lateral lobes. Distance between the two endings of the former longer than half the length of pre-MS.

Pre-vulva: Pre-CD shorter than in P. torvus , narrow and anteriorly with narrow curve ( Fig. 75g View FIGURES 75 ).

Colouration of female (see also description for torvus -group and Psechrus ). Sternum brown to red-brown with yellowish-white median line running end-to-end ( Fig. 82k View FIGURES 82 ). Median bands on carapace clearly serrated. Lateral bands very broad (2.5–3.5x diameter of PME) and clearly serrated. Light longitudinal line ventrally on opisthosoma continuous and (very) narrow. If measured centrally on opisthosoma, its width is 0.2–0.3 times the width of one half of the cribellum.

Variation in colouration pattern: Interestingly in this species a second morph colour pattern exists: The female from Southern Province ( SB 261 ) and one female from ‘Ceylan’ (Simon-Collection, SB 633 ) belong to that morph. It is characterised by the absence of the light longitudinal line ventrally on opisthosoma ( Fig. 81j View FIGURES 81 ) and by the unicoloured yellowish-brown sternum.

Variation of copulatory organs. Females: Distal tips of the branches of tegimentum (TM) may be directed further medially ( Fig. 75e View FIGURES 75 ). Posterior section of MS may be shorter ( Fig. 75e View FIGURES 75 ). Direction of SH may differ slightly ( Fig. 75d View FIGURES 75 ).

Distribution. Sri Lanka ( Fig. 94 View FIGURE 94 ).