Robustagramma dilatatum Cui and Marshall, 2005

Marshall, Stephen A. & Cui, Yongsheng, 2005, Systematics of Robustagramma, a new genus of New World Sphaeroceridae (Diptera), Zootaxa 1026 (1), pp. 1-122 : 31-32

Robustagramma dilatatum Cui and Marshall , new species

( Figs. 42–48 )

Body length 1.2–1.6 mm. General color brown, heavily pollinose but without conspicuous patterns.

Head: Face, gena and antenna brownish yellow; lower frons reddish yellow. Frons lightly pollinose. Interfrontal bristles in 3 pairs. Postvertical bristles slightly shorter than inner occipitals, parallel or convergent. Eye height ca. 2.1–2.3 times genal height. Preapical palpal bristles ca. 1.2–1.5 as long as maximum width of palpus.

Thorax: Acrostichal setulae in 6 rows between anterior dorsocentral bristles. Posterodorsal katepisternal bristle over half as long as distance between bristle base and wing base; anterodorsal katepisternal very small. Wing lightly pigmented, with two indistinct pale bands beyond intersection of R 2+3 and costa. First costal sector slightly thicker than second costal sector. Length of second costal sector 0.38–0.46X length of third. R 2+3 short, distal third curved forward. Costa ending before wing apex, extending past R 4+5 by 0.5–2 vein widths. Stump vein CuA 1 ca. 2 vein widths long. Tarsi and fore tibiae yellow to brownish yellow. Mid femur with 1–2 anterior preapical bristles. Mid tibia of male with an apicoventral bristle and two rows of short ventral bristles or setulae on distal two­thirds; mid femur of male with a row of anteroventral bristles on distal half, and one or 2 irregular rows of small ventral bristles or stout setulae on basal 3/4.

Male terminalia: Sternite 5 nearly twice as long as sternite 4, with a slightly emarginate posteromedial margin and a bare central area. Dorsomedial length of epandrium 0.29X length of sternite 8. Posterior portion of surstylus densely setose, tapering distally. Cercus similar in length to surstylus, with narrow distal halves and slightly ampliate apices. Distiphallus with a pair of dorsal whip­like sclerites and a pair of large ventral sclerites. Postgonite with a straight distal half. Ejaculatory apodeme small.

Female terminalia: Sternite 8 small but entire (not reduced to 2 small sclerites). Spermathecae with distal portions much larger than basal portions.

Holotype (♂, DEBU): BRAZIL: Paraná. Londrina, Mata dos Godoy , 28–31.i.1990, S. A. Marshall.

Other paratypes: BRAZIL: Paraná. Curitiba , 30 km SE BR 277, 6–9.ii.1990, S.A. Marshall (2 ♂, DEBU). São Paulo State. USP Biol. Stn., 5–6.ii.1979, human dung, R. Woodruff and J. Runnacles (2 ♀, DEBU) .

Etymology: The specific epithet refers to the expanded apex of the cercus in lateral view.

Figures

FIGURES 42–48. Robustagramma dilatatum sp. nov.: 42, posterior view of male terminalia; 43, lateral view of male terminalia; 44, lateral view of male internal genitalia; 45, male sternite 5; 46, dorsal view of female terminalia; 47, ventral view of female terminalia; 48, spermathecae.