Cnestus Sampson, 1911

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 Sampson, 1911

Cnestus Sampson, 1911: 383.

Tosaxyleborus Murayama, 1950: 49. Synonymy: Browne 1955: 368.

Type species.

Cnestus magnus Sampson, 1911; monotypy.

Diagnosis.

Cnestus species are typically moderate to large in size, 1.8-5.5 mm, and stout, 1.54-2.75 × as long as wide. Cnestus is a morphologically variable genus but is distinguished by the eye feebly emarginate; lateral margin of the pronotum carinate from base to at least the midpoint; submentum depressed; procoxae narrowly separated; antennal club truncate, types 1 or 2 with segment 1 completely or almost covering the posterior face; antennal funicle 3- or 4-segmented; scutellum flat, flush with elytral surface. Most species have a mesonotal mycangium on the pronotal base.

Similar genera.

Anisandrus , Hadrodemius , Xylosandrus . Cnestus is closely related to Anisandrus , Hadrodemius and Xylosandrus , all of which possess a mesonotal mycangium and the associated dense tuft of hair-like setae at the scutellar area and pronotal base ( Gohli et al. 2017; Johnson et al. 2018).

Distribution.

Distributed throughout Asia, Oceania and South America ( Petrov and Mandelshtam 2018). One species is established in the United States ( Schiefer and Bright 2004).

Gallery system.

The 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 develops.