Diuncus mucronatus (Eggers, 1923)

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

Diuncus mucronatus (Eggers, 1923) Fig. 50G, H, L

Xyleborus mucronatus Eggers, 1923: 191.

Diuncus mucronatus (Eggers): Hulcr and Cognato 2009: 34.

Type material.

The holotype was destroyed in the bombing of UHZM in World War II ( Wood and Bright 1992).

New records.

China: Guizhou, Guiyang, Huaxi, 25.x.2015, Y. Li, ex trap baited with ipsenol + EtOH (MSUC, 1). Hong Kong, Tai Po Kau, vi.2017, J. Skelton (MSUC, 4). Jiangsu, Nanjing, Laoshan National Park, Bacai Road, 32.09156N, 118.583701E, 15.viii.2017, Cognato, Li, Gao, ex Populus (MSUC, 2). Vietnam: Cao Bang, 22°34.118'N, 105°52.537'E, 1048 m, 12.iv.2014, VN13, Cognato, Smith, Pham, ex large felled Pinus sp. (MSUC, 1).

Diagnosis.

2.0-2.5 mm long (mean = 2.26 mm; n = 5); 2.33-2.78 × as long as wide. This species is distinguished by the elytral summit armed by two pairs of large denticles, one pair on interstriae 2 and the other on interstriae 3; pronotum longer than wide; declivity appearing strongly bisulcate; declivital interstriae 1 and 3-6 clearly convex giving the declivity a rugged appearance.

Similar species.

Diuncus haberkorni , D. mucronatulus , D. quadrispinulosus .

Distribution.

China* (Guizhou*, Hong Kong*, Jiangsu*), Indonesia (Java), Japan, East & West Malaysia, New Guinea, Philippines, Thailand, Vietnam*.

Host plants.

Polyphagous ( Browne 1961b).

Figures

Figure 50. Dorsal, lateral and declivital view of Diuncus javanus, 2.5 - 2.7 mm (A, B, I), D. justus, 1.5 - 1.7 mm (C, D, J), D. mucronatulus holotype, 1.5 mm (E, F, K), and D. mucronatus, 2.0 - 2.5 mm (G, H, L).