Robustagramma uniseta 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 : 29-30

Robustagramma uniseta Cui and Marshall , new species

( Figs. 38–41 )

Male: Body length 2.1 mm. General color reddish brown, moderately pollinose.

Head: Frons distinctly flattened, slightly shiny. Face, gena and lower frons reddish; antenna reddish yellow. Ocellar triangle, interfrontal strips and orbital strips lightly silvery, head otherwise dark brown. One well­developed pair of interfrontal bristles, distinctly shorter than orbital bristle. Posterior orbital bristle well developed, anterior orbital bristle absent. Ocellar bristle, inner and outer vertical bristles, and inner and outer occipital bristles well developed. Postocellar bristles cruciate, half as long as postvertical bristle. Eye height ca.1.8 times genal height. Aristal hairs over twice as long as basal width of arista. Palpus with two preapical bristles twice as long as maximum width of palpus; maximum palpal width ca. 1/5 as long as palpus.

Thorax: Dorsocentral bristles in 3 (2 postsutural and one presutural) pairs. Acrostichal setulae in 6 rows between anterior postsutural dorsocentral bristles. Halter knob brown; stem pale. Wing uniformly yellowish. First costal sector distinctly thinner than second costal sector; length ratio of second to third costal sector ca. 0.38; costa ending at wing apex, extending past R 4+5 by 5 vein widths; R 2+3 abruptly curved forward at distal 1/4, with long (5 vein widths) stump vein. Discal cell with an angulate posterior corner and long (3 vein widths) stump of vein CuA 1. Tarsi and fore tibiae yellow. Mid tibia with a single posterodorsal proximal bristle, an anterodorsal bristle near middle, single anterodorsal, dorsal and posterodorsal bristles distally; an apicoventral bristle, and two rows of short, stout bristles on ventral surface of distal two thirds. Mid femur with a row of 4 anterior bristles in distal half; 3 small anteroventral bristles and a row of 6 posteroventral bristles on basal third. Abdomen reddish brown in color, shiny. Tergites with weak, sparse, bristles. Dorsomedial length of epandrium 0.2X length of sternite 8. Sternite 5 with 3 pairs of small stout bristles; posteromedial margin convex. Surstylus slightly longer than cercus, characteristic in shape. Ejaculatory apodeme small, ca. 0.2X length of aedeagal apodeme.

Female: Unknown.

Holotype (♂, DEBU): ECUADOR: Napo. Baeza , 5.iii.1979, S. A. Marshall. Etymology: The name uniseta refers to the single pair of orbital bristles.

Figures

FIGURES 38–41. Robustagramma uniseta sp. nov.: 38, posterior view of male terminalia; 39, lateral view of male terminalia; 40, lateral view of male internal genitalia; 41, male sternite 5.