Nigripeza spangleri, Marshall, 2022

Marshall, Stephen A., 2022, Amapeza and Nigripeza, new genera of Neotropical micropezid flies (Diptera, Micropezidae, Taeniapterinae), Zootaxa 5092 (3), pp. 251-272 : 270-271

Nigripeza spangleri new species

Figures 10A–10D

Description: Colour: Body mostly black, head dark brown dorsally, frontal vitta orange anteriorly but phasing to brown posteriorly. Orbital plate pruinose orange, epicephalon dark shiny brown, ocellar plate small and black. Clypeus dark brown. Fore femur brown basally, yellow distally. Fore tibia dark brown, fore tarsomeres 1–2 white, 3–5 black. Other legs yellowish brown; hind femur with a strong and elongate dark ring in basal third; distomedian and distal rings very faint. Vertical row of katepisternal bristles black. Wing with complete but weak broad discal band. Abdominal pleuron (discoloured on available specimens) apparently dirty white except for the male pleural sac, which is large, brownish with dense black microsetulosity. Female oviscape pruinose basally but otherwise shining dark brown, apex pale.

Head: Frontal vitta almost parallel sided behind ocelli, expanded and slightly elevated in front of ocelli, hardly tapered anteriorly. Orbital plate dulled with very fine striae; epicephalon shiny and bare; paracephalon mostly bare, microsetulose only between postocellar and inner vertical bristles. Clypeus entirely microsetulose.

Thorax: Postpronotal lobe distinctly elevated posteriorly, sparsely microsetulose. One dorsocentral bristle. Suprahumeral bristles absent.

Female abdomen: Major (paired) spermathecal duct elongate and almost parallel-sided, gradually expanded to a bulb-like swollen apex from which short, distally expanded transversely striate, convoluted stems lead to 2 funnel-shaped spermathecae. Spermathecae with distinct outpocketings at base and broad distal invaginations. Minor (single) duct shorter and slightly narrower but similar in shape, single spermatheca large, similar to paired spermathecae.

Male abdomen: Genital fork with very short, broad, parallel-sided and straight arms; 5 short stout bristles on mesal surface, all in apical third, and 3 long outer preapical or apical bristles as long as or longer than length of arm. Distiphallus short and broad, ending in a broad but tapered and distally pointed phallic bulb. Ejaculatory apodeme not clearly visible in only available male, but apparently smaller than epandrium.

Type material: Holotype (♀, USNM) and paratypes (1♂, 1♀, USNM): ECUADOR. Past. Puyo, 31.Jan.1976, Spangler et al, Ecuador Peace Corps Smithsonian Institution Aquatic Insect Survey.

Etymology: Nigripeza spangleri is named after coleopterist Paul Spangler, the collector of this and many other new insect species.

Comments: Nigripeza spangleri is very similar to the closely related N. obscura , the only dark congener with a plumose arista. Both species have a swollen cervical sclerite and a single dorsocentral bristle. Male and female terminalia of these species reflect the close relationship but differ clearly in details such as the shape, dimensions and chaetotaxy of the genital fork and the shape and dimensions of the spermathecae and associated ducts. Nigripeza spangleri is distinctive for its very short genital fork and very large single spermatheca.

Figures

FIGURES 10A–10D. Nigripeza spangleri new species, Ecuador. A, spermatheca and associated structures; B, male sternite 5 and genital fork; C, male terminalia, lateral; D, female.