Talaus triangulifer Simon, 1886

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 : 414-415

Talaus triangulifer Simon, 1886

( Figs 2C , H–J, 4E, 7A–B)

Talaus triangulifer Simon, 1886: 172 .

Type material: Holotype: female, INDONESIA, Sumatra, no more locality data given ( MNHN 8289 , examined by C. L. Deeleman; see remarks below).

Other material examined. INDONESIA: East Kalimantan: 4♂, 1♀, Sepaku (40 km N of Balikpapan), de- graded remains of stand of primary rainforest, general hand collecting, 16 July 1979, P. R. & C. L. Deeleman ( RMNH.ARA.17832). West Sumatra: 1♀, Mt. Singalang, Anai, 480–520 m, general foliage, 22 June 1994, S. Djo- josudharmo ( RMNH.ARA.17834). MALAYSIA: Sabah: 1♀, Sorsinsim, 6° 06′N 116° 50′E, 5 year old adjacent secondary forest loc 21, canopy fogging Melochia umbellata (Stercul.) , 19 February 1997, 500– 700 m, A. Floren ( RMNH.ARA.17835); 1♀, 5° 26′N 116° 08′E, Crocker Range, 20 year old isolated secondary forest, CR.II.5, canopy fogging, Melanolepis glandulosa (Euphorbiaceae) , 18 February 2001, A. Floren ( RMNH.ARA.17833).

Diagnosis. This species is very similar to T. xiphosus , which was described by Zhu and Ono (2007). A much larger series of speciemns are required to review the specific differences, if any. Males of this species are also simi- lar to those of T. opportunus , but are distinguished by the oval tegulum, the longer, broad-based E and configuration of the tibial apophyses. Females may be distinguished from congeners by the oval S, relatively long C shaped CD ( Fig. 4E ).

Description. Male (RMNH.ARA.17832): Total length: 8.0; prosoma length: 4.6, width: 3.8. Leg I: femur 3.0, patella 1.0, tibia 2.8, metatarsus 2.4, tarsus 1.8. Prosoma reddish brown, with some long setae, surface with 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. Palp: VTA large, apically hookshaped; RTA digitiform and well sclerotised. Bulb oval, embolus broad-based, stout, apically pointed ( Figs 2 I–J, 7A–B).

Female RMNH.ARA.17832: Total length: 10.2; prosoma length: 4.6, width: 4.0. Leg I: femur 3.4, patella 1.0, tibia 3.0, metatarsus 2.4, tarsus 1.8. In general, similar to male except for slightly lighter colour, dark spots of the opisthosoma ( Fig. 2C ). Epigynum and vulva as in Figs 2H , 4C .

Distribution. Known from Indonesia (East Kalimantan) and Malaysia (Sabah).

Remarks. The type specimen was examined and drawn by C. L. Deeleman. These drawings were compared with the examined material. The type locality is Sumatra, probably it is Mt Singalang (C. L. Deeleman, pers. comm.). Material from that locality has been examined for this study. The perceived differences in length and curvature of the CD between T. xiphosus and T. triangulifer mentioned in Zhu & Ono (2007) are minor and thus, these species might turn out to be synonyms. Additionally, T. elegans Thorell, 1890 might also turn out to be a junior synonym of T. triangulifer . The sketches of the female type done by C. L. Deeleman during a visit to MCSN in 1987 indicate slight differences from T. triangulifer . Unfortunately, I have been unable to examine the type as it has been misplaced since (M. Tavano, MCSN, pers. comm.).

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 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).