Psechrus torvus (O. Pickard-Cambridge, 1869 )

Bayer, Steffen, 2012, The lace-sheet-weavers — a long story (Araneae: Psechridae: Psechrus), Zootaxa 3379 (1), pp. 1-170 : 127-129

Psechrus torvus (O. Pickard-Cambridge, 1869)

Figs 69a–g , 70a–d , 86g , 89m , 92m

Tegenaria torva O. Pickard-Cambridge 1869: 376 , pl. 11, figs 10–20 ( Description of ♂ and ♀, illustration of ♂). [Lectotype: 1 ♀ ( SB 93 ), here designated, from SRI LANKA (‘Ceylon’): Central Province: Ramboda (‘Rambodde’), ca. N 07°02', E 80°42', 1000–1700 m; J. Nietner leg. ca. 1855; OUMNH; Paralectotypes: 3 ♂ ( SB 264 , 268–269 ), 7 ♀♀ ( SB 263 , 265–267 , 270–271 , 275 ), 1 s.a. ♂ ( SB 274 ), 2 s.a. ♀♀ ( SB 272–273 ), with same data as for lectotype; OUMNH, all type material examined].

Notes on type material: During his stay in Ceylon ( Sri Lanka) between 1852 and 1874, John Nietner spent most of his time in the area of ‘Rambodde’ (presently Ramboda) as plantation owner ( Kraatz 1857), where he collected plenty of insect material ( Nietner 1855). It is likely that he collected the type specimens of Tegenaria torva at the same locality.

The type series contains one specimen (♀ SB 275) belonging to another species (see material list in the species description of P.hartmanni sp. nov.).

Lancaria torva — Karsch 1879: 557 (Transfer from Tegenaria ).

Psechrus torvus — Simon 1887: 194 (Syn. of Lancaria with Psechrus ; Formal transfer from Lancaria ). Karsch 1891: 275 (Syn. with P. argentatus ). Simon 1892: 225 (Removed from Syn. with P. argentatus ), 224, figs 173, 175 (Non description & illustration of ♂, misidentified, see P. hartmanni sp. nov.). Pocock 1900: 211. Simon 1906: 287 (Non record of ♀ from Singapore, misidentified, see P. singaporensis ). Kulczyṅski 1908: 567. Berland and Berland 1914: 133. Sherriffs 1919: 222. Fage 1929: 359. Reimoser 1934: 467 (Non record of ♀ from Pumbarai, India, misidentified, see P. crepido sp. nov.). Kayashima 1962: 9, figs 1–4 (Non illustration of ♀, misidentified, see P. clavis sp. nov.). Lee 1966: 18, figs 3e–g (Non illustration of ♂ and ♀, misidentified, see P. taiwanensis ). Lehtinen 1967: 260, fig. 476 (Non illustration of ♀, misidentified, see P. decollatus sp. nov.). Tikader 1977: 209. Levi 1982: 120, figs 16–28, ad part, figs 23–28 misidentified (Description of ♂ and ♀, figs 16–22: illustration of ♂, s.a. ♀ and ♀). Hu 1984: 57, figs 51.1–3 (Non illustration of ♂ and ♀, misidentified, see P. taiwanensis ). Yin et al. 1985: 19. Song et al. 1999: 398. Song et al. 2002: 373 (Erroneously listed as fauna element of Singapore [according to Simon 1906]. However, to date this species has been recorded only from Sri Lanka and India). Sebastian and Peter 2009: 279, 528.

Psechrus alticeps Pocock 1899: 751 (Description of s.a. ♀). [Syntypes: 1 s.a. ♀ (SB 234), 1 ♂ (SB 235), 1 juv. (SB 1047), all from INDIA: Kerala Province (‘Travancore’): Ponmudi, ca. N 08°45', E 77°07', 700–800 m; H. Ferguson leg. III.1896; NHM 1899˙1˙17˙54–55, all type material examined]. Pocock 1900: 211. Simon 1906: 286. Kulczyṅski 1908: 567. Berland and Berland 1914: 132. Sherriffs 1919: 223. Chamberlin 1924: 2. Fage 1929: 360. Lehtinen 1967: 261 (Syn.).

Note on type material: Pocock (1899) did not mention how many type specimens he had designated and of which sex they were. He only described the (subadult) female, so one would guess that there are no males among type material, but there is one male that is missing both pedipalps. The femur, patella and tibia from the right pedipalp are still present. Maybe the two palpal organs were already lost, when Pocock examined this male, otherwise he should have recognised it as such.

Additional material examined (2 ♀♀, 3 s.a. ♀♀, 1 s.a. ♂). INDIA: Tamil Nadu Province: Anaimalai Sanctuary (20 km SW of Pollachi), Top Slip , ca. N 10°27'30'', E 76°53', 1300–1400 m; W. Eberhard leg. XII.1983; 1 s.a. ♀ ( SB 622 ) , 1 s.a. ♂ ( SB 623 ), MCZ 82514; 1 s.a. ♀ ( SB 168 ), MCZ 82519 . SRI LANKA: Central Province: Pundaluoya , ca. N 07°00'30'', E 80°40', ca. 1100 m; E. E. Green leg. before 1898; 1 ♀ ( SB 260 ) , NHM 1899˙12˙13˙19. Labugolla, Mackwoods Tea Centre , N 07°01'24.5'', E 80°43'07.4'', ca. 1500 m, tea plantation, under large rock; V. Hartmann leg. 10.I.2011; 1 ♀ ( SB 941 , raised from juvenile, pre-epigyne of cuticle of subadult instar was kept), SMF .

Revised diagnosis (see also diagnosis for torvus -group above). Males with long conductor (C) (longer than width of tegulum [T], Figs 70a–c ). Embolus (E) with two helical windings ( Fig. 70c ), tip of harpago (H) pointing proximally ( Figs 70a,c ). Females with distally rounded branches of tegimentum (TM) pointing anterio-medially ( Figs 69a,d , 89m ). First loop of copulatory duct (CD) directed anteriorly, larger than second loop ( Fig. 69b ).

Description. Male:

Body and eye measurements. Carapace length 5.3–7.2, carapace width 3.8–4.8, anterior width of carapace 2.3–2.8, opisthosoma length 5.5–8.2, opisthosoma width 2.3–5.0. Eyes: AME 0.26–0.34, ALE 0.36–0.39, PME 0.33–0.36, PLE 0.36–0.42, AME–AME 0.14–0.24, AME–ALE 0.03–0.04, PME–PME 0.18–0.22, PME–PLE 0.26–0.31, AME–PME 0.44–0.54, ALE–PLE 0.34–0.43, clypeus height at AME 0.51–1.11, clypeus height at ALE 0.43–0.93.

Cheliceral furrow with three promarginal and four retromarginal teeth.

Measurements of palp and legs. Leg formula: 1423. Palp: 7.7–9.5 [2.8–3.4, 1.2–1.6, 1.5–1.7, 2.2–2.8]; Legs: I 45.0–53.3 [10.9–13.8, 2.5–3.4, 12.3–14.4, 12.6–14.3, 6.7–7.4], II 33.6–41.0 [8.8–11.3, 2.3–3.0, 8.6–10.9, 8.9–10.4, 5.0–5.4], III 22.2–26.3 [6.5–7.7, 1.8–2.2, 5.3–6.2, 5.4–6.4, 3.2–3.8], IV 35.4–41.7 [9.0–11.3, 2.0–2.7, 8.5–10.0, 10.0–11.1, 5.9–6.6].

Spination. Palp: 132, 000, 0000; legs: femur I 546, II 546 (556) , III 545 , IV 544 (545) ; patella I–IV 000; tibia I– II 3038 , III 2134 (2124) , IV 3136 (3126) ; metatarsus I 3037, II 3037 (3035) , III 3035 , IV 3036 (3046).

Palpal femur without modification ( Fig. 70d ). MC-I–II and MT-I: absent.

Copulatory organ (see also diagnosis and general description for torvus -group). Harpago arising at 12:30 o’ clock position on tegulum. Conductor with almost pointed tip, embolus base protruding retrolaterally ( Fig. 70b ). Sperm duct with flat curve anterio-prolaterally ( Fig. 70b ). Cymbium dorsally with very dense scopula, covering 2/3 of cymbium. Palpal tibia relatively long ( Figs 70a–c ), its distal retrolateral bulge not very distinct ( Fig. 70b ).

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

Body and eye measurements. Carapace length 8.0 (7.9–9.0), carapace width 5.5 (5.2–6.2), anterior width of carapace 3.7 (3.6–4.0), opisthosoma length 10.8 (10.1–12.6), opisthosoma width 6.0 (5.5–9.2). Eyes: AME 0.38 (0.36–0.38), ALE 0.47 (0.41–0.47), PME 0.45 (0.41–0.48), PLE 0.48 (0.47–0.48), AME–AME 0.24 (0.23–0.27), AME–ALE 0.06 (0.06–0.08), PME–PME 0.34 (0.26–0.34), PME–PLE 0.42 (0.36–0.42), AME–PME 0.63 (0.61–0.65), ALE–PLE 0.53 (0.49–0.54), clypeus height at AME 1.44 (1.21–1.55), clypeus height at ALE 1.16 (1.09–1.38).

Cheliceral furrow with three promarginal and four retromarginal teeth.

Measurements of palp and legs. Leg formula: 1423. Palp: 10.4 (9.9–11.4) [3.5 (3.4–4.2), 1.5 (1.4–1.6), 2.0 (1.9–2.1), 3.4 (3.2–3.5)]; Legs: I 48.7 (43.6–48.0) [12.4 (11.0–13.0), 3.6 (3.3–3.7), 13.2 (12.1–12.8), 12.8 (11.5–12.2), 6.7 (5.7–6.3)], II 37.6 (34.6–38.8) [10.3 (9.8–11.1), 3.0 (3.0–3.5), 9.9 (9.1–9.8), 9.6 (8.4–9.5), 4.8 (4.3–4.9)], III 25.6 (23.4–26.1) [7.6 (7.2–8.1), 2.4 (2.3–2.5), 6.0 (5.4–6.4), 6.3 (5.7–6.5), 3.3 (2.8–3.4)], IV 38.7 (35.1–39.0) [10.5 (9.7–11.2), 2.9 (2.6–3.0), 9.4 (8.4–9.6), 10.2 (9.3–10.0), 5.7 (5.1–5.5)].

Palpal claw with 15 (13–15) teeth.

Spination. Palp: 131{141} (131,141), 110{120} (110,110), 1101 (1101), 1014 (1014); legs (—except for patella— variable, only most common states noted): femur I 546 (546,556), II 546 (546,555) III 545 (545,555), IV 553 (554,454); patella I–IV 000; tibia I– II 3038 (3038), III 2124 (2124,3124), IV 3136 (3136); metatarsus I– II 3037 (3037), III 3035 (3035,3037), IV 3046 (3046,3036,3047).

Copulatory organ (see also diagnosis and general description of torvus -group). Epigyne without (distinct) epigynal field (EF) ( Figs 69a,d , 89m ). Copulatory ducts distinctly larger than receptacula. Spermathecal heads arising anterio-medial on receptacula ( Fig. 69b ).

Primordial copulatory organ. Pre-epigyne: Pre-MS just slightly broader than long, with parallel lateral margins, curves of anterior margins narrow ( Fig. 69g ). Distance between the two endings of anterior margins longer than half the length of pre-MS.

Pre-vulva: Pre-CD long, narrow and anteriorly with narrow curve ( Fig. 69f ).

Colouration of male and female (see also description for torvus -group and Psechrus ). Sternum unicoloured yellowish brown. Median bands on carapace serrated. Lateral bands broad (ca. 2x diameter of PME) and serrated. Light longitudinal line ventrally on opisthosoma mostly continuous, but sometimes broken subdistally and narrow to very narrow. If measured centrally on opisthosoma, its width is 0.1–0.3 times the width of one half of the cribellum.

Variation of copulatory organs. Males only with marginal intraspecific variation in the structures of bulb. Females: Lateral margins of tegimentum (TM) may be with slight curves ( Fig. 69a ) or without ( Fig. 69d ). Vulvae without significant variation ( Figs 69b,e , 92m ).

Remarks: Psechrus alticeps Pocock, 1899 was synonymised with P. torvus by Lehtinen (1967). Though Lehtinen gave no reason for this synonymy, he most likely was right. Firstly, the pre-epigynes of the subadult female syntype of P. alticeps matches the pre-epigyne of a P. torvus specimen from Labugolla, which is very close to type locality. The respective specimen (SB 941) had been raised from juvenile for the present study. After the final moult its exuviae was kept and the pre-epigyne was dissected and examined. Secondly, the pre-epigynes of the s.a. ♀ syntypes of P. torvus match those of P. alticeps , which Levi (1982) had already recognised. Thirdly and finally, the palpal femur of the male syntype of P. alticeps does not show the slightest modification and its palpal tibia is quite long and has a rather indistinct retrolateral bulge distally, like in the male paralectotypes of P. torvus and unlike in similar species related with P. torvus (see below).

Sherriffs (1919) stated that he has observed the webs of P. torvus in the field. Notice that at least a part of the material collected by Sherriffs in Sri Lanka (it is possible that additional material is deposited in other museums or were lost) had been checked in the present study and had proved to belong to other, closely related species.

Jose and Sebastian (2001) reported P. alticeps from Kerala Province, India, which is correct, as the type locality Ponmundi belongs to the present Kerala Province. However, they reproduced the illustrations of the copulatory organs of Fecenia protensa Thorell, 1891 after Tikader (1977, sub Psechrus nicobarensis ) (on this in detail see Bayer 2011, p. 31).

Distribution. Sri Lanka, India ( Fig. 94 ).

Figures

FIGURES 69a–g. Psechrus torvus, from Sri Lanka, Central Prov., ♀ adult and primordial copulatory organ. a–c ♀ lectotype SB 93, d–e ♀ SB 260, f–g s.a. ♀ SB 941. a, d Epigyne, ventral view. b, e Vulva, dorsal view. c Schematic course of internal duct system. f Pre-vulva, dorsal view. g Pre-epigyne, ventral view.

FIGURES 70a–d. Psechrus torvus, ♂ paralectotype SB 264 from Sri Lanka, Central Prov. a–c ♂ palp (a prolateral, b ventral, c retrolateral view). d ♂ left palpal femur, retrolateral view. C: Conductor. CA: Cymbium alveolus. E: Embolus. EB: Embolus base. H: Harpago. SD: Sperm duct. T: Tegulum.

FIGURES 86a–o. Psechrus spp., photos of left ♂ palp. a P.sinensis. b P. triangulus. c P. tingpingensis. d P. obtectus sp. nov. e P. senoculatus. f P. clavis sp. nov. g P. torvus. h P. hartmanni sp. nov. i P. zygon sp. nov.? j P. crepido sp. nov. k P. schwendingeri sp. nov. l P.cebu. m–o P. kunmingensis. a ♂ syntype SB 521 from China, Guizhou Prov. b ♂ paratype SB 882 from China, Yunnan Prov. c ♂ SB 529 from China, Hunan Prov. d ♂ paratype SB 1150 from Vietnam, Bac Thai Prov. e ♂ paratype SB 537 from China, Hunan Prov. f ♂ paratype SB 1008 from Taiwan, Nantou County. g ♂ paralectotype SB 264 from Sri Lanka, Central Prov. h ♂ SB 624 from Sri Lanka. i ♂ SB 848 from Sri Lanka, Central Prov. j ♂ holotype SB 644 from India, Tamil Nadu Prov. k ♂ holotype SB 143 from Philippines, Luzon, Mountain Prov. l ♂ holotype SB 149 from Philippines, Cebu Prov. m–o ♂ from China, Yunnan Prov., Kunming. a–m, o ventral, n prolateral view.

FIGURES 89a–p. Psechrus spp., photos of epigyne, ventral view. a P. sinensis. b P. triangulus. c P. tingpingensis. d P. obtectus sp. nov. e P.fuscaisp. nov. f P. kunmingensis. g P. senoculatus. h P.clavis sp. nov. i P. kenting. j P. taiwanensis. k P. crepido sp. nov. l P. cebu. m P. torvus. n P. hartmanni sp. nov. o P. zygon sp. nov. p P. tauricornis sp. nov. a ♀ paratype SB 524 from China, Guizhou Prov. b ♀ holotype SB 881 from China, Yunnan Prov. c ♀ paratype SB 194 from China, Hunan Prov. d ♀ paratype SB 1153 from Vietnam, Bac Thai Prov. e ♀ holotype SB 954 from China, Yunnan Prov. f ♀ SB 953 from China, Yunnan Prov. g ♀ SB 886 from China, Sichuan Prov. h ♀ paratype SB 614 from Taiwan, Taoyuan County. i ♀ paratype SB 618 from Taiwan, Taitung County. j ♀ holotype SB 238 from Taiwan. k ♀ paratype SB 984 from India, Tamil Nadu Prov. l ♀ paratype SB 151 from Philippines, Cebu Prov. m ♀ SB 941 from Sri Lanka, Central Prov. n ♀ paratype SB 845 from Sri Lanka, Central Prov. o ♀ holotype SB 846 from Sri Lanka, Central Prov. p ♀ paratype SB 849 from Sri Lanka, Central Prov.

FIGURES 92a–p. Psechrus spp., photos of vulva, dorsal view. a P. sinensis. b P. triangulus. c P. tingpingensis. d P. obtectus sp. nov. e P.fuscaisp. nov. f P. kunmingensis. g P. senoculatus. h P.clavis sp. nov. i P. kenting. j P. taiwanensis. k P. crepido sp. nov. l P. cebu. m P. torvus. n P. hartmanni sp. nov. o P. zygon sp. nov. p P. tauricornis sp. nov. a ♀ paratype SB 524 from China, Guizhou Prov. b ♀ holotype SB 881 from China, Yunnan Prov. c ♀ paratype SB 194 from China, Hunan Prov. d ♀ paratype SB 1155 from Vietnam, Bac Thai Prov. e ♀ holotype SB 954 from China, Yunnan Prov. f ♀ SB 953 from China, Yunnan Prov. g ♀ SB 886 from China, Sichuan Prov. h ♀ paratype SB 831 from Taiwan, Chiayi County. i ♀ paratype SB 618 from Taiwan, Taitung County. j ♀ holotype SB 238 from Taiwan. k ♀ paratype SB 984 from India, Tamil Nadu Prov. l ♀ paratype SB 151 from Philippines, Cebu Prov. m ♀ SB 941 from Sri Lanka, Central Prov. n ♀ paratype SB 845 from Sri Lanka, Central Prov. o ♀ holotype SB 846 from Sri Lanka, Central Prov. p ♀ paratype SB 849 from Sri Lanka, Central Prov.

FIGURE 94. Distribution of Psechrus in southern India and Sri Lanka. Symbols: species belonging to the torvus-group. Arrow: Distribution of P. crepido sp. nov.