Grallipeza albiterga, Marshall, S. A., 2013

Marshall, S. A., 2013, Grallipeza Rondani (Diptera: Micropezidae: Taeniapterinae) of the Caribbean and North America, Zootaxa 3682 (1), pp. 45-84 : 53-55

Grallipeza albiterga new species

Figs. 8–12

Description (females only; males unknown): Size: 7–8 mm. Colour: Head mostly orange; clypeus dark shining brown, some specimens with a blue-black sheen; frontal vitta velvet black from anterior margin to behind ocelli ( Fig. 12 ). Thorax patterned in reddish brown and black, scutellum, postpronotum and most of postsutural scutum black, pleuron entirely orange. Fore femur black on distal half, tarsomere one and tarsomere two off-white, other tarsomeres brown. Mid and hind femora with longitudinal black patches on basal ¾ and a distinct dark distal ring.

Katepisternal bristles black. Abdominal tergites two and three white, contrasting with dark tergite one, tergite two usually with circular black markings. Upper half of female abdominal pleuron black except for a yellow strip that reaches junction of t2 and t1, black pigmentation extending around abdomen near apex; oviscape shining black or dark brown (pale brown on one probably teneral type) except for paler tip, tergite 6 shining blue-black (brown on one probably teneral type).

Head: Arista long-haired at least over basal 2/3, longest hair over ½ scape width. Pedicel with long ventroapical bristles, one distinctly longer than first flagellomere. Interantennal distance equal to scape width. Frontal vitta broadened and raised in front of ocelli; narrowed and depressed behind ocelli.

Thorax: Cervical sclerite concave ventrally, concave surface densely covered with distinct circular pits or pores. Postpronotum with scattered long setulae along ventral third. Fore femur with only small ventral setulae. One distinct dorsocentral bristle, 1–3 long exclinate suprahumeral bristles. Wing: Anal cell microsetulose, wing membrane lightly and evenly infuscated over distal 2/3.

Female abdomen: Oviscape strongly constricted at base, about 3 times length of tergite 6 and 2/3 as long as preabdomen. Paired spermathecae large and oval, on short, slender single ducts arising from a distally swollen common duct; swelling of common duct occupying distal third of duct and separated from basal two thirds by a marked constriction ( Fig. 11 ). Single spermatheca with a round central part and elongate-oval, strongly tuberculate lateral lobes.

Type material: Holotype (female, CMNH 332-790) and two paratypes (Ƥ, CMNH # s 328,444 and 318,557): Dominican Republic. Hato Mayor, Parque los Haitises, 3 km W Cueva de Arena, 19-04N, 69-29W, 20 m, 7– 9.vii.1992, R. Davidson et al., mesic lowland forest. Other paratypes: Dominican Republic. La Vega Prov, P.N. Armando Bermudez, La Cienaga de Manabao, 19 ° 04.022’N, 71 ° 51.849’W, 1183m, 19.viii.1986, D. Perez, R. Bastardo, B. Hierro (female, USNM); La Cienaga-Los Tablones, 16–17.viii.2006, D. Perez (2 Ƥ, USNM).

Variation: One of the specimens from La Cienaga has two strong dorsocentral bristles but is otherwise identical to the type of G. albiterga . Intraspecific variation in dorsocentral number is extremely unusual.

Etymology: Grallipeza albiterga is named for its pale, almost white, abdominal tergites 2–3.

Comments: This species is part of a species group including G. nigrivitta and G. pleuritica , all of which share desclerotization of tergites 2–3, a dark lower vitta, and pigmentation of the scutum. Grallipeza albiterga is most distinctive for its largely black female abdominal pleuron (at least the upper half of the pleuron), with the black area interrupted by a white band reaching the junction of T2 and 3.

Figures

FIGURES 8 – 12. Grallipeza albiterga female. 8, right lateral; 9, head right lateral; 10, female terminalia right lateral; 11, spermathecae and ducts; 12, head and thorax dorsal.