Euwallacea Hopkins, 1915

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

Euwallacea Hopkins, 1915

Euwallacea Hopkins, 1915a: 54.

Wallacellus Hulcr & Cognato, 2010a: 27. Synonymy: Storer et al. 2015.

Type species.

Xyleborus wallacei Blandford, 1896b; original designation.

Diagnosis.

1.8-5.7 mm, 2.08-3.6 × as long as wide. Euwallacea is distinguished by a combination of homoplastic characters which include the pronotum typically tall with inflated anterolateral corners, appearing subquadrate to quadrate in dorsal profile (types 3, 4, 8), less commonly with rounded anterior margin (types 2, 4, 7); anterior margin of pronotum unarmed; pronotal disc alutaceous; declivital posterolateral margin with prominent costa or carina; elytral discal interstrial punctures seriate; declivity typically with very sparse setae; and antennal club truncate (type 2) or flattened (type 3), circular or taller than wide. In addition, the scutellum is flush with elytra and flat, mycangial tufts are absent, lateral margin of pronotum obliquely costate, and procoxae are contiguous.

Similar genera.

Fortiborus , Planiculus , Xylosandrus .

Distribution.

Found throughout tropical South Asia and Oceania, rare in temperate East Asia. Six species, including three in the Euwallacea fornicatus species complex, have been introduced to North America ( Gomez et al. 2018a, 2018b).

Gallery system.

This consists of branched tunnels, either in one horizontal plane or extending into three dimensions and penetrating deeply into the wood. Brood chambers are absent. In small diameter stems the galleries may be longitudinal.

Remarks.

Euwallacea species are in need of further taxonomic/phylogenetic investigation given evidence of several non-monophyletic species ( Cognato et al. 2020b).