Taxonomic history

Xyleborus mutilatus Blandford, 1894b: 103.

Xylosandrus mutilatus (Blandford): Wood, 1989: 177.

Cnestus mutilatus (Blandford): Dole and Cognato, 2010: 530.


Xyleborus sampsoni Eggers, 1930: 184. Wood, 1989: 177.

Xyleborus taitonus Eggers, 1939b: 118. Wood and Bright, 1992: 799.

Xyleborus banjoewangi Schedl, 1939b: 41Kalshoven, 1960: 63.


3.6−3.8 mm long (mean = 3.76 mm; n = 5); 1.58−1.73 times as long as wide. This species can be distinguished by the presence of a mesonotal mycangial tuft on the pronotal base; elytral disc very short, two times scutellum length; elytral declivity, obliquely truncate; pronotum type 1 when viewed dorsally; antennal club type 2, with two sutures visible on posterior face; antennal funicle four-segmented; protibia obliquely triangular; procoxae narrowly separated; posterolateral margin of elytra weakly carinate from apex to declivital base along interstriae 7; declivital interstriae granulate, setose with recumbent hairs and often median row of long erect hairs (varies geographically); striae 1 and 2 impressed; discal punctures dense, confused; and uniformly black body.

May be confused with

Anisandrus ursulus, Cnestus gravidus, Cnestus improcerus, and C. testudo


Throughout the Oriental region from India to Indonesia and New Guinea, and extending northwards to Japan, Korea, and Russia (Far East). Introduced and established in the United States (Schiefer and Bright 2004, Gomez et al. 2018a). Recorded in the study region from China (Anhui, Fujian, Guizhou, Hainan, Hong Kong, Jiangsu, Jiangxi, Shaanxi, Shanghai, Sichuan, Yunnan, Zhejiang), Taiwan, Vietnam.

Host plants

polyphagous (Wood and Bright 1992)


The biology of the species has been studied in Japan by Kajimura and Hijii (1992, 1994), in China by Tang (2000), and in U.S.A. by Stone and colleagues (Stone and Nebeker 2007, Stone et al. 2007). The associated ambrosia fungus has been described by Six et al. (2009). It is a pest of young Castanea mollissima (Fagaceae) trees in China (Zhejiang) (Tang 2000), but in USA appears to favor stressed host plants (Stone et al. 2007).

DNA data

Sequences available for COI and CAD.

COI: GU808719MN619875MN619876MN619877MN619878

CAD: GU808641MN620163MN620164MN620165MN620166