Xyleborus glabratus Eichhoff, 1877

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

Xyleborus glabratus Eichhoff, 1877 Fig. 89C, D, J

Xyleborus glabratus Eichhoff, 1877: 127.

Xyleborus kumamotoensis Murayama, 1934: 288. Cognato et al. 2019: 1276.

Type material.

Lectotype Xyleborus glabratus (MIIZ). Lectotype Xyleborus kumamotoensis (NMNH).

Diagnosis.

2.2-2.5 mm long (mean = 2.36 mm; n = 5); 3.14-3.57 × as long as wide. This species is distinguished by declivital interstriae 1 laterally broadened from base to declivital midpoint and then narrowing towards apex; anterior 1/2 of the pronotum strongly shiny; discal interstriae 2 × the width of striae; discal strial punctures 4-5 × the diameter of those of interstriae; declivital striae and interstriae clearly distinguishable; declivital striae flat to feebly impressed; declivital interstriae 1 with at least one large denticle (typically three), numerous closely spaced granules and 1-3 small denticles (typically one); and posterolateral margin of declivity carinate to interstriae 7.

Similar species.

Xyleborus insidiosus , X. mysticulus .

Distribution.

Bangladesh, China (Fujian, Guangdong, Guangxi, Hong Kong, Hunan, Jiangxi, Sichuan), India (Assam, West Bengal), Japan, Myanmar, South Korea, Taiwan, Thailand, Vietnam. Imported to and established in USA ( Rabaglia et al. 2006; Gomez et al. 2018a).

Host plants.

The species has an evident preference for the family Lauraceae , and its attacks are restricted to that family in the US ( Rabaglia et al. 2006; Fraedrich et al. 2008). In the Oriental region, it has also been recorded on a few occasions from other families ( Dipterocarpaceae , Fabaceae , Fagaceae , Pinaceae , Theaceae ) ( Beaver and Liu 2010; Hulcr and Lou 2013), but it is not clear whether it was breeding in these trees.

Remarks.

Although not of economic importance in its native range, the species is an invasive pest in the US, where it transmits a pathogenic fungus ( Raffaelea lauricola ) to a variety of Lauraceae trees (including avocado) ( Harrington et al. 2011). Consequently, its host preferences, attractant volatiles, flight activity and other aspects of its biology, and possible management and control methods, have recently been studied intensively (e.g., Hanula et al. 2008; Hulcr et al. 2011; Brar et al. 2012, 2013; Kendra et al. 2012, 2015, 2016; Formby et al. 2013; Maner et al. 2013; Mayfield et al. 2013; Peña et al. 2015). Recent field collections in its native range revealed that the species exhibits the same biology there as it does in the US ( Hulcr et al. 2017; Cognato et al. 2019).

Figures

Figure 89. Dorsal, lateral and declivital view of Xyleborus festivus, 3.6 - 3.9 mm (A, B, I), X. glabratus, 2.2 - 2.5 mm (C, D, J), X. insidiosus holotype (E, F, K), and X. muticus holotype, 3.0 - 3.1 mm (G, H, L).