Taxonomic history

Xyleborus formosae Wood, 1992: 80 (new name for X. formosanus Browne nec Eggers 1930).

Xyleborus formosanus Browne, 1981a: 131 nec Eggers 1930: 186.

Cyclorhipidion formosanum (Browne): Beaver and Liu 2010: 24.

Xylosandrus formosae (Wood): Smith et al. 2020b: 400.

Diagnosis

2.5−3.0 mm long (mean = 2.76 mm; n = 5); 2.27−2.55 times as long as wide. This species can be distinguished by the narrowly separated procoxae; pronotal mycangial tuft absent; abundant hair-like elytral vestiture; declivital striae and interstriae uniseriate punctate; and declivity rounded, convex, unarmed, surface shagreened, appearing dull.

May be confused with

Anisandrus lineatus, Coptodryas inornata, Cyclorhipidion spp., Euwallacea fornicatus, E. kuroshio, and E. perbrevis

Distribution

China (Fujian, Jiangxi, Xizang), India (West Bengal), Taiwan, Thailand, Vietnam

Host plants

polyphagous; recorded from Amoora (Meliaceae), Machilus (Euphorbiaceae), Michelia (Magnoliaceae), and Saurauia (Actinidiaceae) (Smith et al. 2020b)

Remarks

The unusual morphology of this species is superficially similar to that of several other genera (see similar species above). This presents a challenge in the generic identification of specimens, especially if they are not pinned. Molecular phylogenetics revealed this species belongs in Xylosandrus and represents the only known species of an Australian species group comprised of X. monteithi Dole and Beaver, 2008, X. rotundicollis (Browne, 1984b), and X. woodi Dole and Beaver, 2008 in SE Asia (Cognato et al. review). 

DNA data

Sequences available for COI and CAD.

COI: MN620086MN620087MN620088

CAD: MN620343MN620344MN620345