Allometopon hauseri, Owen Lonsdale, 2016

Owen Lonsdale, 2016, Revision of the genus Allometopon Kertész (Diptera: Clusiidae), Zootaxa 4106 (1), pp. 1-127 : 31-32

Allometopon hauseri spec. nov.

Figs 95–99

Description. General: ( Figs 95, 96 ) Body length 3.6mm. Arista densely plumose with hairs becoming sparser on distal half. M1+2 ratio 3.8. First flagellomere slightly produced anterodorsally at base of arista, which is inserted higher than average. Cell bm partially open. Female unknown.

Chaetotaxy: Two fronto-orbital setae, with anterior seta slightly thinner and 3/5 length. Ocellar seta as long as posteriormost fronto-orbital. Postvertical seta absent. Interfrontal seta very small, barely visible. First flagellomere along distal margin below insertion of arista with hairs as long as width of arista base. Presutural supra-alar present, small. Anterior dorsocentral widely separated from posterior dorsocentral and only slightly shorter. Acrostichal seta absent. One short, thin lateral scutellar seta plus one minute additional seta anteriorly on left side. Setulae sparser posteromedially on scutum.

Colour: Setae yellow. Antenna light yellow with black medial stripe on outer surface of first flagellomere and dorsum of outer surface of first flagellomere brownish, becoming yellower dorsally; frons brown to dark brown with anterior margin and large anteromedial triangle light yellow; back of head with large dark brown dorsomedial spot enclosing one pair of very small, thin yellow spots; remainder of head yellowish-white; parafacial, gena and postgena silvery tomentose. Scutum yellow with broad dark brown medial stripe that encloses dorsocentral setae and is narrowest between suture and anterior dorsocentral. Scutellum dark brown with apex (not including base of lateral setae) yellow. Katatergite dark brown; anatergite and mediotergite dirty white with mediotergite brownish along dorsal and dorsolateral margins. Pleuron yellowish-white; anepisternum yellow and with limited, faint brown anterior mottling; posterior margin of anepimeron dark brown. Legs yellowish-white, becoming yellower past midpoint of femora; fore tarsi brown with base of basal segment yellowish. Wing faintly infuscated. Halter white. Abdomen yellow with tergite 4 to sternite 8 dark brown; sternite 4 brown, sternite 5 dark brown; epandrium dark brown; cercus yellow; surstylus dirty yellow with basal half brown; cercus light yellow.

Male terminalia: ( Figs 97–99 ) Cercus small. Surstylus nearly as long as epandrium and slightly higher, with broad, curved anteodistal margin that grades into a longer, narrower posterodistal lobe; outer surface setose on posterior half; distal and posterior (except base) margins with short, rounded tubercle-like setae on inner surface. Hypandrial arm long, narrow, strongly angled posteriorly; fused to long, shallow lobe with three distal setae. Phallapodeme rod-like. Pregonite ovate, membranous, flanking basiphallus and with two minute apical setae. Postgonite small, narrow, with two minute apical setae. Basiphallus and epiphallus folded into globular, pigmented mass differentiated into separate sclerites posteriorly and at base of distiphallus. Distiphallus approximately 4/5 length of phallapodeme, smooth, bent at base. Paraphallus minute, lobate, smmooth.

Etymology: The specific epithet recognizes one of the collectors of the holotype, M. Hauser.

Distribution: Malaysia (Sabah).

Holotype: MALAYSIA. Sabah (Borneo): Penampang Distr., Kiulu (bamboo forest), 570m, 5˚52′34ʺN, 116˚15′00ʺE [SDG11–20] 18.x.2011, M. Hauser & S. Gaimari (1♂, CSCA).

Comments: A sister-group relationship is strongly supported between Allometopon hauseri and A. artibatum ( Fig. 19 ), especially the dark frons and the highly characteristic shape of the surstylus and basiphallus. These species are differentiated in the key.

Figures

FIGURES 95 – 99. Allometopon hauseri spec. nov., holotype; 95: photo, dorsal; 96: same, lateral; 97: holotype, external genitalia, left lateral; 98: same, posterior; 99: internal genitalia, left lateral.

FIGURES 19 – 23. Allometopon atribatum spec. nov., holotype; 19: photo, dorsal; 20: photo, lateral; 21: external genitalia, left lateral; 22: same, posterior; 23: internal genitalia, left lateral.