Diuncus mucronatulus (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

Diuncus mucronatulus (Eggers, 1930) Fig. 50E, F, K

Xyleborus mucronatulus Eggers, 1930: 199.

Diuncus mucronatulus (Eggers): Hulcr and Cognato 2009: 33.

Type material.

Holotype (FRI).

Diagnosis.

1.5 mm long; 2.37 × as long as wide. This species is distinguished by its minute size; pronotum conical frontally and angulate (type 6) in dorsal view; pronotal summit at anterior 3/8, basal 5/8 punctate; elytral summit armed by two pairs of large denticles, one pair on interstriae 2, the other on interstriae 3; pronotum as long as wide; declivity appearing weakly bisulcate; and interstriae 1 and 3-6 flat to weakly convex giving the declivity a finely sculptured appearance.

Similar species.

Diuncus haberkorni , D. mucronatus , D. quadrispinulosus .

Distribution.

India (West Bengal). The inclusion of Indonesia ( ‘Borneo’, Java), Malaysia and Thailand in the distribution by Maiti and Saha (2004) is in error.

Host plants.

Recorded only from Mesua ( Calophyllaceae ) ( Beeson 1930).

Remarks.

The species was found associated with Xylosandrus mesuae (Eggers) ( Beeson 1930).

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).