A monograph of the Xyleborini (Coleoptera, Curculionidae, Scolytinae) of the Indochinese Peninsula (except Malaysia) and China Author Smith, Sarah M. Department of Entomology, Michigan State University, 288 Farm Lane, East Lansing, Michigan 48824, USA https://orcid.org/0000-0002-5173-3736 camptocerus@gmail.com Author Beaver, Roger A. 161 / 2 Mu 5, Soi Wat Pranon, T. Donkaew, A. Maerim, Chiangmai 50180, Thailand Author Cognato, Anthony I. Department of Entomology, Michigan State University, 288 Farm Lane, East Lansing, Michigan 48824, USA text ZooKeys 2020 983 1 442 http://dx.doi.org/10.3897/zookeys.983.52630 journal article http://dx.doi.org/10.3897/zookeys.983.52630 1313-2970-983-1 7DED4CE2934C4539945F758930C927F9 C890C7FD4B2D57A8B1A062305ED42D53 Xylosandrus Reitter, 1913 Xylosandrus Reitter, 1913: 83. Apoxyleborus Wood, 1980: 90. Synonymy: Wood 1984 : 229. Type species. Xyleborus morigerus Blandford, 1894a; monotypy. Diagnosis. Xylosandrus species are small to moderately sized, 1.3-3.9 mm, and stout 1.79-2.6 x as long as wide. Xylosandrus is distinguished by the procoxae widely separated (narrowly separated in X. formosae ); pronotum with a median mycangial tuft (absent in X. formosae ); antennal club type 1, obliquely truncate with segment 1 covering the posterior face (flat and type 4 in X. spinifer ); eyes moderately to deeply emarginate; scutellum visible, flat, flush with elytra; lateral margin of the pronotum obliquely costate; protibiae distinctly triangular or slender with fewer than six large socketed denticles; and declivity with zero, five or six striae. Similar genera. Amasa , Anisandrus , Cnestus , Diuncus , Hadrodemius . Xylosandrus is closely related to Anisandrus , Cnestus , and Hadrodemius , all of which possess a mesonotal mycangium and the associated dense tuft of hair-like setae at the scutellar area and pronotal base ( Gohli et al. 2017 ; Johnson et al. 2018). Distribution. Globally distributed throughout temperate and tropical forests. Gallery system. The species typically breed in small diameter stems. The gallery system consists of a radial gallery leading to an irregular chamber in the center of the stem with longitudinal branches extending up and down the stem. Remarks. Xylosandrus was recently revised by Dole and Cognato (2010) but two additional species have since been described ( Gomez et al. 2020 ; Park et al. 2020 ) and one species, X. ramulorum (Schedl, 1957), was transferred from Amasa ( Sittichaya et al. 2019 ). Preliminary phylogenies suggest that Anisandrus maiche is monophyletic with Xylosandrus ( Cognato et al. 2020b ).