Robustagramma atratum 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 : 19-21

publication ID	https://doi.org/ 10.11646/zootaxa.1026.1.1
publication LSID	lsid:zoobank.org:pub:3EDC6787-C73B-4969-BA06-022D0532364F
DOI	https://doi.org/10.5281/zenodo.5052542
persistent identifier	https://treatment.plazi.org/id/0392570D-FFB5-426F-FEDA-ABA882B3FD4D
treatment provided by	Felipe
scientific name	Robustagramma atratum Cui and Marshall
status	sp. nov.

Treatment

Robustagramma atratum Cui and Marshall View in CoL , new species

( Figs. 2–8 View FIGURES 2–8 , 363 View FIGURES 363–370 )

Body length 1.7–2.2 mm. General color brown to black, lightly pollinose, except shining abdomen and tibiae.

Head: Face, gena, antenna and lower frons reddish to dark brown. One pair of conspicuously strong interfrontal bristles and one pair of interfrontal setulae between interfrontal bristles and ptilinal suture. Two orbital bristles, anterior orbital bristle ca. 2/3–3/4 as long as posterior. Postocellar bristles over half as long as postvertical bristles, convergent or cruciate. Eye height ca.1.8–2.1 times genal height. Aristal hairs ca. 2 times as long as basal width of arista. Palpus with several thin ventral bristles and two stout preapical ventral bristles; preapical palpal bristles 2.0–2.3 times as long as greatest width of palpus.

Thorax: Dorsocentral bristles in 3 (two postsutural and one presutural) pairs, anterior pair similar in length to middle prescutellar acrostichal bristles. Acrostichal setulae in 8 rows between anterior postsutural dorsocentral bristles. Posterodorsal katepisternal bristle very long, over 4/5 as long as distance between bristle base and wing base; anterodorsal katepisternal bristle very small. Halter knob brown; stem yellow. Wing clear except for lightly pigmented anterior marginal area.

First costal sector thinner than second costal sector; basal 1/6–1/4 of second costal sector distinctly dark. Ratio of second to third costal sector ca.0.45. Costa ending at or near wing apex, extending past R 4+5 by 1–3 vein widths. Distal quarter of R 2+3 abruptly curved forward. Discal cell with an angulate posterior corner and a long stump of vein CuA 1. Tarsi and fore tibiae reddish yellow except for brownish pretarsi. Mid tibia with a single posterodorsal proximal bristle, an anterodorsal bristle near middle, and an anterodorsal, dorsal and posterodorsal distally; dorsal bristle small; an additional smaller anterodorsal bristle anterior to dorsal bristle. Mid femur with a row of anterior bristles in distal half, a small posterodorsal apical bristle, and a row of strong anterodorsal setulae. Mid tibia of male with an apicoventral bristle and two rows of strong ventral setulae in distal half. Mid femur of male with a row of weak anteroventral and a row of 5–6 posteroventral bristles on basal third.

Male abdomen: Tergites uniformly dark to black and similar in length. Bristles of tergites 4, 5 and epandrium very long, lateral marginal bristles on tergite 5 longer than tergite 5. Epandrial length dorsomedially 0.25–0.33X length of sternite 8. Sternite 5 ca. 1.5 times length of sternite 4, with two dense patches of stout bristles on central area. Cercus short, subtriangular in shape. Surstylus reddish yellow to brownish, characteristic in shape with two broad, setulose lobes (fig. 2, 3). Postgonite with a thick distal half; ejaculatory apodeme very small.

Female abdomen: Tergites 1–7 uniformly pigmented and entire. Sternite 8 entire. Spermathecae with distal portion larger than basal portion. Paired spermathecae with ducts ca. 1.5 times length of spermatheca.

Holotype (♀, INBC) and paratypes (2 ♂, 1 ♀, DEBU): COSTA RICA: Puntarenas. Monteverde Biol. Res., 1500m, cloud forest, 11–13.vi.2000, S. A. Marshall.

Other paratypes: Same data as holotype, but dated 13.vi.2000 (1 ♂, INBC) ; 12.vi.2000, on dung (1 ♀, INBC) . COSTA RICA: San José. Zurquí de Moravia , 1600m, v.1991, P. Hanson (1 ♀, INBC) .

Etymology: The specific epithet, from the Latin for “dressed in black”, refers to the color of this species.