Cnestus bicornioides (Schedl, 1952)

Smith, Sarah M., Beaver, Roger A. & Cognato, Anthony I., 2020, A monograph of the Xyleborini (Coleoptera, Curculionidae, Scolytinae) of the Indochinese Peninsula (except Malaysia) and China, ZooKeys 983, pp. 1-442 : 1

Cnestus bicornioides (Schedl, 1952) Fig. 32E, F, K

Xyleborus bicornioides Schedl, 1952a: 368.

Cnestus bicornoides (Schedl): Browne 1955: 360.

Type material.

Holotype (NHMW).

New records.

China: Tibet [Xizang], Chayu, Shama, 2020 m, 21.vii.1973, ex Fagaceae sp. (NMNH, 2). S Yunnan, Xishuangbanna, 25 km NW Jinghong, vic. Zhang Zhi Chang (NNNR), 22°11.06'N, 100°39.05'E, 780 m, rubber plantation, EKL, 6.iv.2009, L. Meng (RABC, 1). Thailand: Chiangmai, Khun Chang Kian Highld Agr. Res. Stn, 18°50'23"N, 98°53'53"E, 1200-1300 m, 12.ii.2014, T. Saowaphak, ex EtOH trap (RABC, 2); as previous except: 26.ii.2014 (RABC, 2).

Diagnosis.

3.3-3.7 mm long (mean = 3.42 mm; n = 5); 2.36-2.75 × as long as wide. This species is distinguished by the absence of a mesonotal mycangial tuft on the pronotal base; elongate body; declivity excavated; pronotum from dorsal view type 6; pronotum apex strongly produced, extending to a process with two serrations; mandibles normal; epistoma entire; elytral punctures distinct, clearly uniseriate; declivital interstriae bearing sparse erect hair-like setae; declivital interstriae 2-5 sparsely denticulate; protibiae very slender with three large narrow denticles; antennal club type 2, with two sutures visible on the posterior face; and 3-segmented antennal funicle.

Similar species.

Cnestus bicornis (from Indomalayan region), C. quadrispinosus .

Distribution.

China* (Xizang, Yunnan), India (Andaman Is, West Bengal), West Malaysia, Philippines, Thailand*.

Host plants.

Recorded from Shorea ( Dipterocarpaceae ), Swietenia ( Meliaceae ) ( Browne 1961b) and Fagaceae .

Remarks.

The entries in Maiti and Saha (2004) under the name Cnestus cruralis (Schedl) refer to this species, which was earlier ( Maiti and Saha 1986; Saha and Maiti 1996) referred to as C. bicornioides . The species described as Xyleborus cruralis Schedl belongs in the genus Microperus ( Beaver 1998).

Figures

Figure 32. Dorsal, lateral and declivital view of Cnestus ater (holotype Xyleborus retusiformis), 3.9 - 4.1 mm (A, B, I), C. aterrimus (lectotype C. pseudosuturalis), 1.8 - 2.6 mm (C, D, J), C. bicornioides holotype, 3.3 - 3.7 mm (E, F, K), and C. gravidus, 5.0 - 5.5 mm (G, H, L).