Xylosandrus borealis Nobuchi, 1981

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

Xylosandrus borealis Nobuchi, 1981 Fig. 93A, B, I

Xylosandrus borealis Nobuchi, 1981b: 34.

Type material.

Holotype (NIAES).

New records.

China: Guangdong, Shimentai, 28.iii.2003, P. Grootaert (RABC, 1). Hong Kong, Tai Po Kau, vi.2017, J. Skelton (MSUC, 1). Taiwan: Nantou, Sun Moon Lake, 28.vii.2014, C.-S. Lin (MSUC, 5).

Diagnosis.

2.0-2.2 mm long (mean = 2.12 mm; n = 5); 2.0 × as long as wide. This species is distinguished by its moderate size; elytral disc flat, longer than declivity; declivital face steep, abruptly separated from disc; elytra obliquely truncate; posterolateral margins of elytra carinate to interstriae 7; declivital face with four apparent granulate striae (striae 5 short, converging with striae 4 forming a loop); declivital face convex; striae setose, setae semi-recumbent hair-like and equal to the width of an interstria; interstriae granulate, granules multiseriate, confused with a uniseriate row of very long erect hair-like setae longer than the width of two interstriae and confused semi-erect setae approximately the width of an interstria; strial granules large, 1-1.5 × larger than those of interstriae; pronotum longer than wide, from dorsal view conical frontally (type 6) and lateral view taller (type 2), summit at basal 1/4, basal 1/4 shagreened, dull, densely punctate; and broad, dense mycangial tuft on the pronotal base.

Similar species.

Xylosandrus beesoni , X. discolor , X. diversepilosus .

Distribution.

China* (Guangdong*, Hong Kong*), Japan, Korea, Taiwan*.

Host plants.

Only reported from Styrax ( Styracaceae ) and Camellia ( Theaceae ) ( Dole and Cognato 2010).

Figures

Figure 93. Dorsal, lateral and declivital view of Xylosandrus borealis, 2.0 - 2.2 mm (A, B, I), X. brevis, 2.75 - 2.9 mm (C, D, J), X. compactus, 1.5 - 1.9 mm (E, F, K), and X. crassiusculus, 2.3 - 2.9 mm (G, H, L).