Allometopon nobile Frey, 1960

Owen Lonsdale, 2016, Revision of the genus Allometopon Kertész (Diptera: Clusiidae), Zootaxa 4106 (1), pp. 1-127 : 47-48

Allometopon nobile Frey, 1960

Figs 194–199

Allometopon (Calometopon) nobile Frey, 1960: 20 . Sasakawa 1977: 236 [catalogue, Orient]; Papp et al. 2006: 190 [ Thailand].

Description. General: ( Figs 194–196 ) Body length 3.5–4.6mm. Arista sparsely short plumose. M1+2 ratio 2.2–2.6. First flagellomere small, ovate. Clypeus small, narrow.

Chaetotaxy: Three fronto-orbital setae (anterior seta slightly shorter). Ocellar and postvertical setae thin, subequal in length to fronto-orbitals. Interfrontal seta absent. First flagellomere without any longer hairs. Frons glossy, bare, with very few minute setulae anterolaterally. Presutural supra-alar seta present, thin. Two dorsocentral setae, closely set posteriorly; anterior dorsocentral seta and acrostichal seta very thin and less than half length of posterior dorsocentral. Two thin lateral scutellar setae; sometimes small additional seta present anteriorly.

Colour: Setae black. Head predominantly dark brown; antenna yellow; face white with lateral margin glossy black, similar to parafacial; mouthparts with brownish tint except for yellowish-orange palpus; gena and postgena shiny; venter of gena glossy black. Thorax mostly dark brown; scutum withnarrow yellowish margin around scutellum laterally; with yellow anterolateral stripe on shoulder (at least on posterior region of postpronotum and anterior margin of notopleuron, but sometimes including all of postpronotum and large dorsal band on notopleuron) that continues onto whitish proepisternum and fore coxa. Wing clouded along R2+3 and in first radial cell on distal half. Halter white. Legs yellow with fore coxa whitish, mid and hind coxae light yellow; distal ¼ of fore and hind femora (except apex) dark brown, mid femur brown excluding apex, tibiae dark brown and tarsomeres light yellow to whitish. Abdomen dark brown with tergite 1 (and sometimes also tergite 2), surstylus and cercus yellow to reddish-yellow; terminalia yellow in female.

Male terminalia: ( Figs 197–199 ) Annulus well-developed with seventh spiracle enclosed within sclerite. Epandrium broadly rounded, with apex slightly constricted and lateral surface somewhat bulging. Cerci narrow and rounded, widely separated. Surstylus small, narrow, pointed, and curved inwards; inner posterobasal margin with narrow, serrated process that is as long as surstylus itself. Ventral lobe of hypandrium short, rounded and bare; arm of hypandrium stout, broadly rounded. Phallapodeme rod-like, well-developed with anterior margin possibly fused to hypandrium. Pregonite large, ovate, membranous and with cluster of medial setulae. Postgonite small and shallowly lobate, fused to membrane connecting pregonite and hypandrium. Basiphallus half length of phallapodeme and densely “haired” dorsally. Epiphallus free from basiphallus, heavily sclerotized, strongly projecting and with spinulose membrane posteriorly. Distiphallus 1/3 length of phallapodeme with small laterobasal outgrowths.

Female terminalia: Not dissected.

Distribution: Burma.

Lectotype: BURMA. N.E. Burma, Kambaiti, 7000ft., 11.v.1934 (1♂, MZHF).

Paralectotypes: BURMA. N.E. Burma, Kambaiti, 2000m, 25.v.1934, Malaise (1♂, MZHF), 17.v.1934 (1♀, MZHF), 1.vi.1934 (1♀, MZHF) [allotype], 14.v.1934 (1♂, MZHF).

Additional material examined: BURMA. Same locality as lectotype, 25.v.1934 (1♂, MZHF), 21.v.1934 (1♂, MZHF), 23.v.1934 (1♂, MZHF), 17.v.1934 (1♂, MZHF), 29.v.1934 (1♂, MZHF), N.E. Burma, Kambaiti, 7000ft., R. Malloch, 20.v.1934 (1♂, BMNH), 23.v.1934 (1♂, BMNH)..

Comments: Allometopon nobile is a readily diagnosed species with a presutural supra-alar seta, highly contrasting, dark colouration, a saw-like basal process on the small, pointed surstylus and an elongate, “haired” basiphallus. A male syntype in good condition is here designated and labeled as the lectotype for A. nobile in order to better fix and further stabalize the concept of this species.

Figures

FIGURES 194 – 199. Allometopon nobile Frey; 194: paralectotype female, photo, dorsal; 195: same, anterior; 196: same, lateral; 197: non-type male, external genitalia, left lateral; 198: same, posterior; 199: internal genitalia, left lateral.