Robustagramma longiseta 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 : 23-25

Robustagramma longiseta Cui and Marshall , new species

( Figs. 18–24 )

Body length 1.5–1.9 mm, general color brown to dark brown, moderately pollinose.

Head: Face, gena, antenna and lower frons yellowish to reddish brown. One well­developed pair of interfrontal bristles, similar in size to posterior orbital bristle. Two orbital bristles, anterior bristle 2/3 as long as posterior; uppermost orbital setula present between orbital bristles. Postocellar bristles weak or absent. Eye height ca. 2.3–2.5 times genal height. Aristal hairs twice as long as basal width of arista. Palpus slightly thickened, maximum width ca.1/4 of palpal length. Two preapical palpal bristles, slightly longer than maximum width of palpus.

Thorax: Dorsocentral bristles in 3 (2 postsutural and one presutural) pairs, presutural dorsocentral bristles slightly longer than acrostichal setulae but shorter than middle prescutellar acrostichal bristles. Acrostichal setulae in 6 regular rows between anterior postsutural dorsocentral bristles. Posterodorsal katepisternal bristle over 2/3 as long as distance between bristle base and wing base; anterodorsal katepisternal bristle very small. Halter knob brown, stem white. Wing clear. First costal sector thinner than second sector. Length of second costal sector ca. half length of third. Distal quarter of R 2+3 abruptly curved for­ ward, without a stump vein. Costa ending near wing apex, extending past R 4+5 by 2 vein widths. Discal cell with an angulate posterior corner, without appendices. Tarsi and fore tibia yellow to brownish yellow. Mid tibia with a single posterodorsal proximal bristle, an anterodorsal bristle near middle, and an anterodorsal, dorsal and posterodorsal distally; dorsal bristle very small. Mid femur with a row of 3 anterior bristles on distal half. Mid tibia of male with an apicoventral bristle and several short, stout ventral bristles in distal half. Mid femur of male with a regular row of 6 postventral bristles on basal half.

Male abdomen: Abdominal tergites uniformly dark, slightly shiny and similar in length. Sternite 5 over 1.5 times as long as sternite 4, with 6 prominent pairs of long, depressed bristles, and a black, smooth, shiny, hemispherical posteromedial protuberance. Epandrium with long, stout bristles; dorsomedial length of epandrium 0.4X length of sternite 8. Ejaculatory apodeme very small.

Female abdomen: Tergites 1–7 uniformly pigmented and entire. Sternite 7 truncate posteriorly. Sternite 8 entire. Spermathecae with distal portion larger than basal portion, and with ducts similar in length to spermathecae.

Holotype (♂, INBC): COSTA RICA: Alajuela. Volcán Tenorio, N slope near Bijagua Biol. Stn., 700m, RET over Atta mound, 16–20.vi.2000, S. A. Marshall.

Paratypes: COSTA RICA: Cartago. Braulio Carillo N.P., 10 10 N, 84 07 W, 500m, 10.iv.1985, H. Goulet and L. Masner (1 ♀, DEBU) . Same data as previous label, but collected by L. Masner (1 ♀, DEBU) . PERU: Madre de Dios. Manu Natl. Pk., Cocha Coshu Biol. Sta.; 390m, 2–4.x.1986, D. C. Darling (1 ♀, DEBU) .

Etymology: The specific name refers to the long­setose sternite 5 of the male.

Figures

FIGURES 18–24. Robustagramma longiseta sp. nov.: 18, posterior view of male terminalia; 19, lateral view of male terminalia; 20, lateral view of male internal genitalia; 21, male sternite 5; 22, dorsal view of female terminalia; 23, ventral view of female terminalia; 24, spermathecae.