Robustagramma nigrivittatum 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 : 51-53

Robustagramma nigrivittatum Cui and Marshall , new species

( Figs. 121–127 )

As described for Robustagramma crassipalpus except as follows. Body length 1.8–2.1 mm. Face, gena, antenna and lower frons reddish yellow. Interfron­ tal bristles in 3 pairs plus a pair of interfrontal setulae. Postvertical bristles convergent, similar in length to outer occipitals, slightly shorter than inner occipitals. Eye height ca. 1.9 times genal height. Aristal hairs ca. 2.5 times as long as basal width of arista. Preapical palpal bristle slightly longer than maximum palpal width; submedial palpal bristle distinctly shorter than maximum palpal width.

Prosternum with 2 pairs of setulae. Acrostichal setulae in 6 rows between anterior dorsocentral bristles. Length of second costal sector ca. 0.55–0.68X length of third. Mid tibia with a single dorsal proximal bristle, a small anterodorsal submedian bristle, and an anterodorsal, dorsal and posterodorsal bristle distally. Mid femur with 4–5 anterior bristles on distal half and a small posterodorsal apical bristle. Mid tibia of male with an apicoventral bristle and several very small bristles on ventral surface of distal quarter.

Male terminalia: Sternite 5 over 1.5 times as long as sternite 4, with 2 or 3 dense rows of long bristles, a prolonged posteromedial margin, and a black middle vitta. In posterior view, lower interior margin of surstylus with many small strips. Cercus short, pointed in lateral view. Ejaculatory apodeme small, shorter than 1/6 of length of aedeagal apodeme.

Female terminalia: Anterolateral portions of two sclerites of sternite 8 narrow, tapering. Sternite 10 large, mainly setulose.

Holotype (♂, DEBU): ECUADOR: Pichincha. 4 km S Sto. Domingo, Río Palenque Station , 250m, 17–25.ii.1979, FIT, S. A. Marshall.

Paratype: ECUADOR: Río Palenque , dung trap day 3, 24–25.iii.1976, S. Peck (1 ♀, DEBU) .

Etymology: The specific name refers to the black strip on sternite 5 of the male.

Figures

FIGURES 121–127. Robustagramma nigrivittatum sp. nov.: 121, posterior view of male terminalia; 122, lateral view of male terminalia; 123, lateral view of male internal genitalia; 124, male sternite 5; 125, dorsal view of female terminalia; 126, ventral view of female terminalia; 127, spermathecae.