Arixyleborus yakushimanus (Murayama, 1958)

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

Arixyleborus yakushimanus (Murayama, 1958) Fig. 30E, F, I

Xyleborus yakushimanus Murayama, 1955: 83.

Arixyleborus yakushimanus (Murayama): Nobuchi 1985: 28.

Type material.

Holotype (NMNH).

New records.

China: Jiangxi, Long Nan, 12.vii.2016, Lv-Jia, Lai, S-C., ex Cyclobalanopsis glauca (RABC, 1). Yunnan, Xishuangbanna Sanchahe Nat. Res., 22°09.784'N, 100°52.256'E, 2186 m, 29-30.v.2008, A. Cognato (MSUC, 1). India: Bengal [Bihar], Dahura, Kurseong, 22.x.[19]33, N.C. Chatterjee (NMNH, 4). [West Bengal], Kalimpong, Samsingh, 18.iv.1934, N.C. Chatterjee, ex Castanopsis sp. (NMNH, 1). Laos: Vientiane, Ban Van Eue, 15.ii.1966, native collector, ex malaise trap (BPBM, 1). Taiwan: Nantou, Sun Moon Lake, 16.vi.2016, C.-S. Lin (MSUC, 2). Vietnam: Cao Bang, 22°34.118'N, 105°52.537'E, 1048 m, 12-17.iv.2014, Cognato, Smith, Pham, ex FIT (MSUC, 7). Thua Thien-Hue, Bach Ma N.P., 16.22897, 107.85349, 415 m, 15.ii.2017, VN55, A.I. Cognato, T.A. Hoang, ex 5 cm diameter (MSUC, 28; NHMUK, 2; NMNH, 2; VMNH, 4).

Diagnosis.

2.0-2.2 mm long (mean = 2.08 mm; n = 5); 2.5-2.75 × as long as wide. This species is distinguished by the protibiae posterior faces inflated, granulate; antennal club wider than long; posterolateral carina costate; pronotum lateral margin distinctly costate, nearly carinate; pronotum anterior margin elevated with a row of serrations; strial furrows equal in width to interstrial ridges on disc; interstrial ridges glabrous or with minute setae no longer than 1/2 width of a strial furrow; interstrial ridges finely tuberculate; striae moderately impressed; declivity strongly shagreened; and moderate size.

Similar species.

Arixyleborus grandis , A. malayensis , A. tuberculatus .

Distribution.

China (Fujian, Jiangxi, Sichuan, Xizang, Yunnan), India* (Bihar, West Bengal), Japan, Laos*, Taiwan*, Thailand, Vietnam*.

Host plants.

Recorded from Castanopsis ( Fagaceae ) and Machilus ( Lauraceae ) ( Yin et al. 1984).

Remarks.

The record of Arixyleborus malayensis from Doi Pui, Chiang Mai, Thailand in Beaver et al. (2014), and other unpublished records from this area, should be referred to this species. The species apparently occurs only in the north of the country and is replaced by A. malayensis in the central and southern regions.

Figures

Figure 30. Dorsal, lateral and declivital view of Arixyleborus titanus holotype, 5.2 mm (A, B, G), A. tuberculatus paratype, 1.35 - 1.5 mm (C, D, H), and A. yakushimanus, 2.0 - 2.2 mm (E, F, I).