Euwallacea sibsagaricus (Eggers, 1930)

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

Euwallacea sibsagaricus (Eggers, 1930) Fig. 58C, D, J

Xyleborus sibsagaricus Eggers, 1930: 196.

Euwallacea sibsagaricus (Eggers): Wood 1989: 173.

Xyleborus dalbergiae Eggers, 1930: 196. Synonymy: Wood 1989: 173.

Xyleborus tonkinensis Schedl, 1934a: 39. syn. nov.

Type material.

Holotype Xyleborus sibsagaricus (FRI). Cotype Xyleborus dalbergiae (NMNH, 1). Holotype Xyleborus tonkinensis (NHMW).

New records.

China: Yunnan, Xishuangbanna, Jinghong City, Jinghong Farm, 21.785N, 100.790E, 677 m, 18.vii.2018, Lai S-C., Zhang L., ex Hevea brasiliensis (RABC, 1). India: Arunachal Pradesh, Etalin vicinity, 28°36'56"N, 95°53'21"E, 700 m, 12-25.v.2012, L. Dembický (ZFMK, 1). Meghalaya, 3 km E Tura, 25°30'N, 90°14'E, 1150 m, 4.v.1999, Dombický, Pacholátko (NHMB, 1). Vietnam: Central Tonkin, [Tuyen Quang], Chiem-Hoa, viii-ix.[no year given], H. Fruhstorfer (NHMW, 1). Tonkin, Hoa-Binh, De Cooman, 1926 (NMNH, 1); as previous except: 1940 (MNHN, 2).

Diagnosis.

3.4-3.9 mm long (mean = 3.58 mm; n = 5); 2.77-2.83 × as long as wide. This species is distinguished by its slender form; declivital posterolateral margin costate and granulate, pronotum appearing subquadrate when viewed dorsally (type 3); protibiae outer margins distinctly triangular bearing five short broad obtuse denticles; declivital strial punctures approximately the same size on disc and declivity; declivity very steep; and declivital surface strongly shiny.

Similar species.

Euwallacea luctuosus , E. subalpinus , Heteroborips tristis .

Distribution.

China* (Yunnan), India (Arunachal Pradesh*, Assam, Meghalaya*, West Bengal), Indonesia (Maluku), East Malaysia, Philippines, Vietnam.

Host plants.

Recorded from Ehretia ( Ehretiaceae ), Sapium ( Euphorbiaceae ), Casearia ( Salicaceae ) ( Beeson 1961), and Hevea brasiliensis ( Euphorbiaceae ).

Remarks.

Images of the Xyleborus dalbergiae and X. sibsagaricus holotypes and the holotype specimen of X. tonkinensis was compared to each other and found to be conspecific and X. tonkinensis is here placed in synonymy.

Figures

Figure 58. Dorsal, lateral and declivital view of Euwallacea semirudis, 3.1 - 3.3 mm (A, B, I), E. sibsagaricus, 3.4 - 3.9 mm (C, D, J), E. similis, 2.3 - 2.5 mm (E, F, K), and E. subalpinus holotype, 2.4 mm (G, H, L).