Jacaena thakek (Jäger, 2007) Jager, 2007

Dankittipakul, Pakawin, Tavano, Maria & Singtripop, Tippawan, 2013, Revision of the spider genus Jacaena Thorell, 1897, with descriptions of four new species from Thailand (Araneae: Corinnidae), Journal of Natural History 47 (23), pp. 1539-1567 : 1553

Jacaena thakek (Jäger, 2007) comb. nov.

( Figures 1 F, 5 G–I, 10 D–F)

Sesieutes thakek Jäger, 2007: 48 , figs 73–82, description of ♂.

Type material

Holotype: ♂, Laos, Khammouan Province, 9.5 km northeast of Thakek, 159 m, 17◦26.936′ N, 104◦52.499′ E, sieving leaf litter in front of cave, 30 October 2004, P. Jäger and V. Vedel leg. ( SMF –56635, examined, Figures 1 F, 5 G–I, 10 D–F) .

Diagnosis

This species seems to be closest to J. mihun , because both species have very distinctly enlarged PME; their palps can be distinguished from other members of Jacaena by the pear-shaped bulb anteriorly narrowed, and the apex of the short, triangular conductor is pointing apically ( Figures 4 G–I cf. 5 G–I). The male of this species can be separated from that of J. mihun by the absence of a small, triangular denticle on the dorsal surface of the conductor ( Figure 10 A cf. 10 D). However, we have a private notion that the boundary between these two species is vague and J. thakek comb. nov. is possibly a junior synonym of J. mihun . Much larger samples would be needed to corroborate these slight differences as species-specific rather than intraspecific variation because more material recently obtained suggests that J. mihun has relatively broad distribution covering northern and north-eastern parts of Thailand (and most likely extending eastwards to Laos where J. thakek comb. nov. was collected).

Distribution

Known only from the type locality, Khammouan Province, Laos.

Figures

Figure 1. Males of Jacaena spp., habitus, dorsal (A – H). Jacaena schwendingeri comb. nov., holotype (A); J. lunulata sp. nov., holotype (B); J. punctata sp. nov., holotype (C); J. mihun (D); J. erawan comb. nov. (E); J. thakek comb. nov., holotype (F); J. schwendingeri comb. nov. (G); J. lunulata sp. nov., paratype (H). DS, dorsal scutum.

Figure 4. Jacaena spp. Male palps, ventral (A, D, G). Ditto, prolateral (B, E, H). Ditto, retrolateral (C, F, I). Jacaena schwendingeri comb. nov., holotype (A – C); J. lunulata sp. nov., paratype (originally misidentified as Sesieutes schwendingeri) (D – F); J. mihun, holotype (G – I).

Figure 10. Jacaena mihun, holotype (A – C); J. thakek comb. nov., holotype (D – F). Male palp, ventral (A, D). Ditto, prolateral (B, E). Ditto, retrolateral (C, F).