Allometopon punctulatum Sasakawa, 1993

Owen Lonsdale, 2016, Revision of the genus Allometopon Kertész (Diptera: Clusiidae), Zootaxa 4106 (1), pp. 1-127 : 55-56

Allometopon punctulatum Sasakawa, 1993

Figs 234–238

Allometopon punctulatum Sasakawa, 1993: 5 .

Description. General: ( Figs 234, 235 ) Body length 3.0mm. Arista pubescent. M1+2 ratio 4.0. Gena and postgena relatively shallow and pilose (excluding posterior half of postgena). First flagellomere ovate, relatively high, produced dorsally and ventrally. Female unknown.

Chaetotaxy: Three fronto-orbitals. Ocellar seta small. Postvertical seta minute. Interfrontal seta absent. First flagellomere with longer apical hairs. Two missing dorsocentral setae (anterior socket smaller), closely spaced posteriorly. One pair of acrostichal setae (missing). One pair of lateral scutellar setae (missing).

Colour: Setae yellow. Body primarily yellow; first flagellomere light yellow; ocellar tubercle brown; back of head widely dark dorsomedially; anepisternum with small central brown spot with faded margin; legs paler; abdomen (from Sasakawa (1993)) testaceous yellow with tergites 4, 5 and epandrium excepting ventral side dark brown. Gena silvery tomentose. Wing lightly infuscated on distal half, becoming clear towards posterior margin and with darker cloud along R2+3.

Male terminalia: ( Figs 236–238 ) [From original description—genitalic dissection in poor condition]. Surstylus higher than epandrium, subtriangular with anterodistal margin shallowly concave and posterobasal corner extended as narrow rounded process exceeding margin of epandrium; inner marginal surface with long stout setae and several small apical tubercle-like setae. Hypandrium very broad with two medial setae and arm short. Phallapodeme rod-like. Pregonite membranous, subcircular and with two medial setae. Postgonite lobate with several apical setae. Basiphallus relatively long and flat, fused to similarly long, flat epiphallus. Distiphallus apparently simple, less than half length of phallapodeme. Paraphallus almost as long as distiphallus, welldeveloped, apically tapering, spinulose on dorsal surface past base.

Distribution: Malaysia ( Sarawak).

Holotype: MALAYSIA. Sarawak, Sadong, Kampong Tapuh, 300–450m, 4–9.vii.1958, T.C. Maa (1♂, BPBM).

Comments: Diagnostic of Allometopon punctulatum is a pubescent arista and a mostly yellow body with a small anepisternal spot, tergites 4 and 5 and the epandrium brown. The large subtriangular surstylus with a small posterobasal process exceeding the posterior margin of the epandrium is also characteristic, and suggests a relationship with A. plicatum (see comments for Allometopon plicatum ).

Figures

FIGURES 234 – 238. Allometopon punctulatum Sasakawa, holotype; 234: photo, dorsal; 235: same, lateral; 236: external genitalia, left lateral; 237: inner surface surstylus; 238: internal genitalia, right lateral. Illustrations from Sasakawa (1993).