Hadrodemius comans (Sampson)

Beaver, Roger A., 2010, A review of the genus Hadrodemius Wood, with new synonymy and a key to species (Coleoptera: Curculionidae: Scolytinae), Zootaxa 2444, pp. 51-57 : 54

Hadrodemius comans (Sampson)

( Figs 1 –2, 7–8)

Xyleborus comans Sampson, 1919: 109 .

Hadrodemius comans (Sampson) : Wood & Bright, 1992: 819. Xyleborus amorphus Eggers, 1926: 147 . Syn.n.

Xyleborus metacomans Eggers, 1930: 188 . Syn.n.

Taxonomy: I have examined female syntypes of H.comans (NHML) and X.amorphus (NMW), and compared them with specimens in my own collection (RAB) from Brunei, Taiwan, Thailand and West Malaysia. I have also compared the latter with specimens in NMB from Laos and Vietnam. It has not been possible to examine the holotype of X.metacomans from India held by the Forest Research Institute, Dehra Dun, but I have compared a specimen from Thailand which agrees very well with Eggers' description of the species. X.amorphus from Taiwan was separated by Eggers (1926, 1939) because the discal striae are distinct and have larger punctures than those on the interstriae, whereas in H.comans from Malaysia and Indonesia the strial and interstrial punctures are of similar size and the striae are indistinct. However, specimens from Vietnam and Laos are intermediate in this respect. Eggers (1930) distinguished the Indian species, X.metacomans from H.comans by the denser and finer puncturation of the elytral declivity, and the denser and longer vestiture. The declivity is also matt rather than shining. However, these characters are rather variable in H.comans , and insufficient to distinguish species. I have also compared a male syntype of X.amorphus (NMW) and males from Brunei Darussalam, Taiwan and West Malaysia in my collection. They are almost identical, and not specifically separable. It is clear that there is only a single rather variable species. The male has been described by Eggers (1939, as X.amorphus ), and Kumar & Chandra (1977, as X.metacomans ).

Distribution: Brunei, China (Fujian, Xizang), India (Assam, West Bengal), Indonesia (Java, Kalimantan, Sumatra), Laos, Malaysia, Myanmar, Taiwan, Thailand, Vietnam.

New Records: BRUNEI, Kuala Belalong FSC, 4o34’N, 115o7E, dipterocarp forest, 220 m, aerial FIT, 8.vi.1991 (N.Mawdsley) (1); as previous except: 275 m, 3.vii.1991 (1); as previous except: 260 m, 16.vii.1991 (1) (NHML); LAOS, Bolimkhamxai prov., Ban Nape (8km NE), 18o21’N, 105o08’E, c. 600m, 1–18.v.2001 (V.Kubán) (1) (NMB); THAILAND, Chiangmai, Doi Suthep, 7.viii.2002 (R.A.Beaver, K.Koivisto) (1) (RAB); VIETNAM, Tonkin, Vinhphu prov., Tandao, 2–11.vi.1985 (V.Kubán) (1) (NMB).

Biology: A polyphagous species recorded from at least 14 families and 22 genera of angiosperm trees. Browne (1961) briefly describes the gallery system, which is typical of the genus.

Figures

FIGURE 1. Dorsal and lateral views of Hadrodemius species. 1 – 2: H. comans female; 3 – 4: H. globus female; 5 – 6: H. pseudocomans female; 7 – 8: H. comans male.