Cnestus protensus (Eggers, 1930)

Sittichaya, Wisut, Smith, Sarah M. & Beaver, Roger A., 2019, Ten newly recorded species of xyleborine ambrosia beetles (Coleoptera, Curculionidae, Scolytinae, Xyleborini) from Thailand, ZooKeys 862, pp. 109-127 : 117-118

Cnestus protensus (Eggers, 1930) Fig. 7 A–F

Xyleborus protensus Eggers, 1930: 201.

Cnestus protensus (Eggers): Schedl 1958: 145.

Diagnosis.

Large, 4.0 mm long (N = 1); stout, 2.0 times longer than wide; body strongly shining, glabrous, black in color; pronotum from dorsal view conical frontally (type 6; Hulcr et al. 2007), pronotal apex strongly produced, armed with numerous strong serrations, anterior portion of pronotum strongly asperate, lateral margins parallel from the base to the middle, base densely coarsely punctate; mesonotal mycangial tuft absent on pronotal base; elytra round, elytral declivity strongly rounded and convex.

Material examined.

THAILAND, Khao Lak-Lam Ru National Park, Phang Nga Province, 8°39'22.4"N, 98°17'31.6"E, tropical rainforest, ethanol-baited trap, 01.xii.2014 (1) (W. Sittichaya).

Distribution.

India (Meghalaya), Indonesia (Java). New to Thailand.

Biology.

Unknown. Cnestus species, as far as is known, are twig and shoot-borers, and the gallery system is typical of such species with a short radial or circumferential gallery running to the middle of the stem, and longitudinal branches up and down the stem in which the brood develop ( Browne 1961, Hulcr and Cognato 2013).

Remarks.

This species can be distinguished from all other Cnestus recorded in Thailand by the strongly produced pronotal apex armed with strong serrations, prono tal base without a mycangial tuft, elytral declivity strongly rounded and convex. This species most closely resembles C. nitidipennis (Schedl), and can be distinguished by the distinctly larger size, much larger, coarser and more numerous pronotal apical serrations, punctures on pronotal base clearly coarser and denser, and sides of pronotum parallel for approximately half of the total length.

Figures

Figure 7. Cnestus protensus (Eggers, 1930) A lateral view B dorsal view C posterolateral view D front E antenna F declivity.