Xylosandrus beesoni Saha, Maiti & Chakraborti, 1992

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 beesoni Saha, Maiti & Chakraborti, 1992 Fig. 92E, F, K

Xylosandrus beesoni Saha, Maiti & Chakraborti, 1992: 11.

Type material.

Holotype (ZSI ( Maiti and Saha 2004)). Not examined.

New records.

China: Yunnan, Kunming, 27.v.2013, J. Hulcr (UFFE, 1); S. Yunnan, Xishuangbanna, 23 km NW Jinghong. vic. Na Ban Village (NNNR), 22.10'N, 100.39'E, 700-1000 m, v-vii.2009, leg. L. Meng (RABC, 1). India: Arunachal Pradesh, Etalin vicinity, 28°36'56"N, 95°53'21"E, 700 m, 12-25.v.2012, L. Dembický (MSUC, 2; ZFMK, 2). Thailand: Chiang Mai, Doi Pui, 16.i.2005, R.A. Beaver (RABC, 1); as previous except: 1400 m, 29.viii-2.ix.2005, W. Puranasakul, ex EtOH trap (RABC, 1); Doi Suthep, ~ 1400 m, 18.x.2004, R.A. Beaver (RABC, 2). Vietnam: Lao Cai, Hoang Lien N.P., 22.35, 103.77, 1500-2000 m, 19.v.2019, VN172, S.M. Smith, A.I. Cognato (MSUC, 13). Ninh Binh, Cuc Phuong N.P., 20.28055, 105.67765, 5-7.iii.2018, 198 m, A.I. Cognato, S.M. Smith, ex FIT (MSUC, 1).

Diagnosis.

2.2-2.7 mm long (mean = 2.43 mm; n = 4); 2.0-2.25 × 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 less than the width of an interstria; interstriae granulate, granules multiseriate, confused with a uniseriate row of erect hair-like setae longer than the width of 1.5 interstriae and confused semi-erect hair-like setae equal to the width of an interstria; strial granules 2 × 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 borealis , X. discolor , X. diversepilosus , X. subsimiliformis .

Distribution.

China (Yunnan)*, India (Arunachal Pradesh*, West Bengal), Thailand*, Vietnam*.

Host plants.

Recorded only from Symplocos ( Symplocaceae ) ( Maiti and Saha 2004).

Remarks.

This species was collected in great abundance by SMS and AIC in Lao Cai province, Vietnam. In nearly all collecting events the species was found in small branches (1-5 cm in diameter) that were dry and often exposed to full sun, an unusual feeding habit, as most other xyleborines are unable to thrive under these conditions. Thai specimens were recorded as Xylosandrus subsimiliformis by Dole and Cognato (2010) and Beaver et al. (2014).

Figures

Figure 92. Dorsal, lateral and declivital view of Xylosandrus adherescens, 2.0 mm (A, B, I), X. amputatus, 2.8 mm (C, D, J), X. beesoni, 2.2 - 2.7 mm (E, F, K), and X. bellinsulanus holotype, 3.9 mm (G, H, L).