Xyleborus Eichhoff, 1864

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

Xyleborus Eichhoff, 1864

Xyleborus Eichhoff, 1864: 37.

Anaeretus Dugès, 1888: 141. Synonymy: Hagedorn 1910b: 98.

Progenius Blandford, 1896a: 20. Synonymy: Hagedorn 1910b: 98.

Mesoscolytus Broun, 1904: 125. Synonymy: Beaver 1998: 181.

Boroxylon Hopkins, 1915a: 58. Synonymy: Schedl 1952c: 162.

Type species.

Bostrichus monographus Fabricius, 1793; subsequent designation: Lacordaire, 1865: 381.

Diagnosis.

1.9-3.9 mm, 2.5-3.51 × as long as wide. Xyleborus is distinguished by a combination of homoplastic characters which include the scutellum flush with elytra and flat; mycangial tufts are absent; lateral margin of pronotum obliquely costate; procoxae contiguous; pronotum from dorsal view rounded frontally (types 0, 2, 6, 7), rarely quadrate (type 4 in X. bidentatus ); elytral disc longer than declivity; elytral disc strial and interstrial punctures seriate; pronotal disc alutaceous; posterior face of the protibiae flat, unarmed; antennal club typically obliquely truncate with segment 1 nearly covering the entire posterior face (type 2), or flattened (type 3); antennal funicle 4-segmented; and anterior margin of pronotum typically unarmed (serrations on a carina in X. bidentatus ).

Similar genera.

Cryptoxyleborus , Fortiborus , Heteroborips , Planiculus , Stictodex .

Distribution.

Widespread throughout temperate and tropical regions of the world.

Gallery system.

The gallery system usually consists of irregularly branched tunnels, usually in one horizontal plane, but sometimes spreading into three dimensions, and without brood chambers. However, given the heterogeneity of the genus, it is not surprising that there are variations on this pattern. In some species, small brood chambers may be present.

Remarks.

Xyleborus is in need of further taxonomic/phylogenetic investigation given its likely polyphyly ( Cognato et al. 2020b).