Talaus nanus Thorell, 1890

Benjamin, Suresh P., 2020, Distributional and taxonomic notes on the crab spider genus Talaus Simon, 1886 with description of a new species (Araneae: Thomisidae), Zootaxa 4858 (3), pp. 405-416 : 407-411

Talaus nanus Thorell, 1890

Figs 2A, B, G, K , 3 A–E, 4A–D

Talaus nanus Thorell, 1890: 15 . Thorell 1895: 312.

Microcyllus nanus (Thorell) . Thorell 1892: 121.

Type material. Holotype: 1 immature female, INDONESIA: Java, no exact locality data available, leg. Beccari ( MCSN, examined).

Other material examined. MALAYSIA: Sabah: 1♂ (opisthosoma missing), North of Tamparuli, 50–100 m, roadside shrub, general beating shrubs, 01 July 1979, G. Perrault ( RMNH.ARA.17842); 1♂ 3♀, West Sabah, road Tuaran-Ranau, 900 m, degraded forest, general collecting, 30 June 1979, P. R. & C. L. Deeleman ( RMNH. ARA.17843); 1♂, West Sabah, 5º 59’ N 116º 42’E, Kinabalu National Park, Poring, 5–700 m, primary forest, loc 1, night fogging canopy, Aporosa sp. ( Euphorbiaceae ), tree DA8, 26–27 February 1996, A. Floren ( RMNH. ARA.17840); 20♂ (3 damaged) 14♀, West Sabah, 6° 06′N 116° 50′E, Sorinsim, 5yr old adjacent secondary for- est, loc 19 SW1, 500– 700 m, canopy fogging, Melochia umbellata (Stercul.) , tree 1 fog 1, 16 February 1997, A. Floren ( RMNH.ARA.17839); 9♂ 4♀, same locality, loc 25 SW1, tree 4 fog 1, 18 February 1997, leg. A. Floren ( RMNH.ARA.17841); 51♂ 20♂, same locality, loc 29 SW1, tree 5 fog 6, 10 March 1997, leg. A. Floren ( RMNH. ARA.17845); 7♂ 4♀, same locality, loc 35 SW1, 500– 700m, tree 11 fog 1, 16 February to 12 March 1997, leg. A. Floren ( RMNH.ARA.17846). Sarawak: 1♀, Matang Reserve, Mount Serapi, 350 m, primary forest, general beating shrub, 11 January 1984, P. R. & C. L. Deeleman ( RMNH.ARA.17838). Pahang: 1♂, Cameron Highlands National Park, general beating shrub, 5 June 1979, G. Perrault ( RMNH.ARA.17844).

Diagnosis. This species is similar to T. beccarii sp. nov., but is distinguished by the hook-shaped VTA and RTA, presence of a cymbial flange in about 2 o’clock position and filiform embolus winding once around tegulum. Females may be distinguished from congeners by the kidney-shaped S and relatively shorter C-shaped CD ( Figs 4 A–D).

Description. Male (RMNH.ARA.17839): Total length: 7.0; prosoma length: 3.6, width: 3.6. Leg I: femur 2.2, patella 1.0, tibia 2.0, metatarsus 1.8. tarsus 1.4. Prosoma red-brown, without markings. ALE, PLE on tubercles, not connected to each other. ALE>PLE>AME>PME, MOA wider than long, distance between AMEs one diameter of AME. Distance between PME more than 4x AME. One small cheliceral tooth. First two legs darker than the restNo markings on opisthosoma except for the rounded muscle spots. Palp as in Figs 3 A–D, 4A–B. Tibia with ventral, retrolateral and dorsal apophyses: ventral apophysis well developed, longer, apically hooked; retrolateral apophysis curved; dorsal apophysis least developed, denticulate. Bulb rounded, embolus long and filiform, winding once around tegulum.

Female (RMNH.ARA.17839): Total length: 9.0; prosoma length: 4.0, width: 3.8. Leg I: femur 2.6, patella 1.2, tibia 2.0, metatarsus 1.4; tarsus 1.6. In general, similar to male except for slightly lighter colour. Epigynum and vulva as in Figs 3E , 4 C–D.

Remarks. The examined material generally fits the descriptions of Thorell (1890, 1892). However, since no material from the terra typical has been examined, the distribution of this species needs to be assessed in future studies.

Distribution. Indonesia (Java), Malaysia (Pahang, North Borneo, Sarawak) and Myanmar.

Figures

FIGURE 2 A–K. A–B, G, K Talaus nanus (G, K immature female from MCSN); C, H–J T. triangulifer from Indonesia, Kalimantan (RMNH.ARA.17832); D T. oblitus male from Sri Lanka (OUMNH b1242 t.8); E, F T. opportunus syntypes from Sri Lanka (OUMNH b1239). A, C, E, G female, habitus dorsal; B, D, F male, habitus dorsal; H epigynum, ventral; I, J right male palp (I ventral, J retrolateral); K epigynal area of immature female. Scale lines = 0.1 mm (H, K), 0.2 mm (I, J), 0.5 mm (A–C), 1.0 mm (G).

FIGURE 3 A–E. Scanning electron micrographs of Talaus nanus from Indonesia, Kalimantan (RMNH.ARA.17839). A left male palp, ventral/retrolateral view; B cymbium modification of unknown function; C RTA, ventral; D tibial apophyses, ventral; E epigynum, ventral. Scale bars = 20 μm (B–E), 100 μm (A).

FIGURE 4 A–E. A–D Talaus nanus from Indonesia, Kalimantan (RMNH.ARA.17839); E T. triangulifer from Indonesia, Kalimantan (RMNH.ARA.17832). A left palp, ventral; B same, retrolateral; C, E epigynum, ventral; D vulva, ventral. Scale lines = 0.2 mm (A, B), 0.1 mm (C–E).