Neoephydra abrupta (Cresson)

Mathis, Wayne N. & Marinoni, Luciane, 2016, Revision of Ephydrini Zetterstedt (Diptera: Ephydridae) from the Americas south of the United States, Zootaxa 4116 (1), pp. 1-110 : 45-47

12. Neoephydra abrupta (Cresson)

Figs. 61–63 , Map 12

Dimecoenia abrupta Cresson 1935: 352 .— Oliveira 1954a: 188 [list].— Wirth 1968: 23 [Neotropical catalog].—Lizarralde de Grosso 1989: 58 [list, Argentina].— Mathis and Zatwarnicki 1995: 238 [world catalog].

Neoephydra abrupta .— Mathis 2008: 10 [generic combination].

Diagnosis. Specimens of N. abrupta are distinguished from similar congeners of the araucaria group by the following characters: appearance dimorphic, either dark, particularly the legs, or pale, with orangish yellow legs; face moderately setose; gena moderately short; and structures of male terminalia with distinctive conformation. Medium-sized to moderately large shore flies, body length 3.62–4.23 mm; generally dull, grayish brown to gray, somewhat subshiny dorsally.

Head: Head ratio 0.63–0.66; frontal ratio 0.51–0.53; mesofrons with dark, greenish blue, metallic luster, pilose laterally; ocellar triangle and parafrons nearly concolorous, microtomentose, brownish gray to charcoal gray; parafrons more charcoal colored anteriorly; fronto-orbits with narrow strip through insertions of fronto-orbital setae subshiny, with faint metallic reflections, concolorous with mesofrons; number of fronto-orbital setae usually 2, sometimes with a larger seta posterior of others. Antenna mostly concolorous, blackish brown. Facial ratio 0.96– 0.99; moderately setulose particularly along oral margin and toward posteroventral portions of face; dorsum of interfoveal hump with subshiny area more or less concolorous with mesofrons, otherwise face densely microtomentose, grayish yellow, paler along oral margin. Eye ratio 0.87–0.90; gena-to-eye ratio 0.35–0.38; gena moderately short, coloration gray to whitish gray but with faint tinges of olivaceous green posteriorly.

Thorax: Mostly microtomentose; scutum mostly brown, subshiny to shiny, with brassy brown metallic luster, more uniformly dark and subshiny posteriorly, anterior margin more microtomentose, especially postpronotum, grayish brown; pleural areas paler, more gray colored ventrally; anepisternum with central area and dorsal margin brownish, otherwise paler, olivaceous gray to brown; other pleural areas including coxae palely olivaceous white to more whitish gray ventrally. Wing length averaging 3.90–3.95 mm; mostly very palely infuscate, faintly brownish; costal vein ratio 0.19–0.22; M vein ratio 0.74–0.76. Leg coloration variable, either dark generally, femora greenish to bluish gray, microtomentose, or mostly paler, yellowish red, particularly tibiae and tarsi.

Abdomen: Generally microtomentose and unicolorous, grayish olivaceous green to gray, paler toward lateral margins, some specimens with faint bluish tinges of metallic luster; ventral surface of tergites frequently whitish gray. Tergite 5 of male somewhat trapezoidal, truncate apically. Male terminalia ( Figs. 61–63 ): margins of epandrium in posterior view parallel, rounded dorsally; surstyli in posterior view roughly forming isosceles triangle, apices of processes forming ventral angle with narrow gap between; surstylus in lateral view with posterior process tapered gradually to bluntly rounded apex, anterior margin irregularly shaped, posterior margin more regular; lateral process extremely short, as angulate bump indicated by patch of long medioapical setulae.

Type material. The holotype male is labeled “ Argentin [a] MENDOZA 17. XII. 0 4 [17 Dec 1904] [light green, date handwritten]/coll. Lichtwardt/Ƌ/ TYPE Dimecoenia ABRUPTA Ƌ T. Cresson, Jr. [red, name and sex handwritten].” The holotype is double mounted (minute nadel in foam block), is in fairly good condition (some setae of the head are missing, and the wings are tattered along the posterior margin), and is deposited in the ANSP. Allotype female and one male paratype (head missing) are labeled with the same label data as the holotype except for the type label and sex symbol as appropriate. Cresson's original description lists the depository of the holotype as “Deut. Ent. Inst.” The cited depository of DEI for the holotype is either an error or the specimen was not returned.

Type locality. Argentina. Mendoza: Mendoza (32°53'S, 68°49'W).

Additional specimens examined. ARGENTINA. La Rioja: Carrizal Bajo (28°53'S, 67°33'W), Oct 1958, L. E. Peña (3♂; MZUSP). Mendoza: Uspallata (32°40'S, 69°21.9'W), 1977, M. L. de Grosso (15♂, 13♀; FML).

CHILE. Atacama: Canto del Agua (28°09'S, 70°56'W), 6 Oct 1966, M. E. Irwin (2♂, 2♀; USNM). Coquimbo: Freirina (28°30.3'S, 71°04.6'W), Oct 1969, L. E. Peña (3♂, 1♀; USNM).

Distribution (Map 12): Neotropical: Argentina (La Rioja, Mendoza) and Chile (Atacama, Coquimbo).

Remarks. This species, like N. ciligena , has two basic color forms. The holotype is a representative of the dark form, i.e., legs mostly microtomentose, grayish green to grayish blue. The second form is pale colored, i.e., legs at most thinly microtomentose, mostly yellowish to orangish. The conformation of the male terminalia of both forms is virtually identical.

MAP 12. Distribution map for Neoephydra abrupta (Cresson) .

Figures

FIGURES 61 – 63. Structures of male terminalia of Neoephydra abrupta (Cresson). (61) epandrium, cerci, surstyli, posterior view; (62) same, lateral view; (63) surstylus, lateral view.