Xyleborinus attenuatus (Blandford, 1894)

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

Xyleborinus attenuatus (Blandford, 1894) Fig. 82E, F, K

Xyleborus attenuatus Blandford, 1894b: 114.

Xyleborinus attenuatus (Blandford): Beaver and Liu 2010: 30.

Xyleborus alni Niisima, 1909: 160. Synonymy: Knížek 2011: 246.

Xyleborus canus Niisima, 1909: 161. Synonymy: Smith et al. 2018b: 397.

Type material.

Holotype Xyleborus attenuatus (NHMUK). Syntypes of Xyleborus canus should be housed in NIAES but have not been located ( Smith et al. 2018b).

New records.

China: Chongqing, Wu Xi, 4.viii.2015, Wang, J-G., Lv-Jia, Tian-Shang, ex Pinus armandii (RABC, 2). Shaanxi, Feng Xian, 20-22.v.2016, Nie, Yang (MSUC, 1). Vietnam: Cao Bang, 22°36.402'N, 105°52.397'E, 1601 m, 13.iv.2014, VN17, Cognato, Smith, Pham, ex standing stump (MSUC, 1); as previous except: 22°36.804'N, 105°51.982'E, 1831 m, 17.iv.2014, VN44, Cognato, Smith, Pham, ex fallen tree, 10 cm branch (MSUC, 1).

Diagnosis.

2.6-2.9 mm long (mean = 2.78 mm; n = 5); 2.9-3.25 × as long as wide. This species is distinguished by the declivital face with interstriae 2 armed by granules at declivital summit, unarmed on declivital face; denticles of declivital interstriae 3 larger than those of interstriae 1; denticles pointed, spine-like, slightly incurved; denticles on interstriae 5 large, sharply pointed, spine-like, curved slightly downwards; discal interstriae 1 and 2 unarmed; declivital interstriae 2 flattened; and large size.

This species is nearly identical to X. thaiphami and is distinguished by the declivital interstriae 3 denticles that are incurved rather than acutely pointed and interstriae 5 denticles always down-curved.

Similar species.

Xyleborinus saxesenii , X. subgranulatus , X. subspinosus , X. thaiphami .

Distribution.

China* (Chongqing, Shaanxi), Japan, Korea, Russia (Far East), Taiwan. Introduced and established in central and northern Europe and North America ( Knížek 1988; Hoebeke and Rabaglia 2007; Gomez et al. 2018a).

Host plants.

Previously recorded from trees in the families Betulaceae , Fagaceae and Rosaceae ( Beaver and Liu 2010). Recorded here from Pinus ( Pinaceae ).

Figures

Figure 82. Dorsal, lateral and declivital view of Xyleborinus andrewesi, 1.9 - 2.0 mm (A, B, I), X. artestriatus, 2.3 - 2.8 mm (C, D, J), X. attenuatus, 2.6 - 2.9 mm (E, F, K), and X. cuneatus holotype, 2.1 - 2.2 mm (G, H, L).