Taxonomy

Euwallacea Hopkins, 1915a: 54.

Synonyms

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

Diagnosis

1.80−5.50 mm long, 2.08−3.60 times 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, and 8), less commonly with rounded anterior margin, (types 2 and 7); anterior margin of pronotum unarmed; pronotal disc alutaceous; posterolateral margin of declivity with prominent costa or carina; elytral discal interstrial punctures seriate; elytral declivity typically with very sparse setae; and antennal club obliquely truncate (type 2) or flattened (type 3), circular or taller than wide. In addition the scutellum flush with elytra and flat, mycangial tufts absent, lateral margin of pronotum obliquely costate, and procoxae contiguous.

May be confused with

Fortiborus, Planiculus, and Xylosandrus

Distribution

Found throughout tropical South Asia and Oceania, rare in temperate East Asia. Multiple species near E. fornicatus introduced to North America (Gomez et al. 2018).

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 is arguably one of the most challenging Xyleborini genera, as it contains a number of species that are clearly defined with molecular data but for which few diagnostic morphological characters exist.