Nocticanace austra Mathis & Marinoni

Mathis, Wayne N. & Marinoni, Luciane, 2012, A conspectus on the Canacidae (Diptera) of Brazil, ZooKeys 162, pp. 59-92 : 67-69

Nocticanace austra Mathis & Marinoni sp. n. Figs 3-6

Diagnosis.

As in the species group diagnosis with the following additions: Small to moderately small beach flies, body length 1.80-2.40 mm, of the galapagensis group (see key to species groups). Head (Figs 3-4): 3 large dorsoclinate and 1 inclinate genal setae. Thorax: Scutellar disc with 1 pair of setae, apical scutellar setae very shallowly curved, not distinctly oriented dorsally compared with lateral scutellar setae. Legs generally gray, with basitarsomeres blackish gray dorsally. Abdomen: Tergites generally gray or slightly brownish gray medially. Male terminalia as follows (Figs 5-6): Epandrium in posterior view bearing long setulae on dorsal half, with medial projection at level of dorsal 1/3 from each lateral arm, forming a cercal cavity, but cerci not evident; medial margin thereafter ventrally forming a wide cavity that narrows ventrally because of medially directly surstyli; surstylus broadly attached or fused to ventral margin of epandrium, in lateral view only slightly narrower than ventral portion of epandrium, essentially an extension of epandrium, slightly swollen posteroventrally, bearing numerous short setulae along posterior margin, ventral margin shallowly bifurcate, forming posterior and anterior lobes, posterior lobe slightly shorter than anterior lobe, gently rounded; anterior lobe more robustly developed than posterior lobe, bluntly rounded to truncate apically, very slightly produced anteroventrally as a shallow, obtuse, point, in posterior view with posterior lobe of surstylus extended medially, pointed apically, anterior lobe more broadly developed apically.

Type material.

The holotype male is labeled "BRAZIL. São Paulo: Praia do Estaleiro (23°20.5'S, 44°53'W; beach), 30Mar2010[,] D. & W. N. Mathis/USNM ENT 00118071 [plastic bar code label]/HOLOTYPE ♂ Nocticanace austra Mathis & Marinoni, DZUP [red]." The holotype is double mounted (minuten in a block of plastic), is in excellent condition, and is deposited in DZUP. Five paratypes (4♂, 1♀; DZUP, USNM) bear the same label data as the holotype.

Other Specimens examined from Brazil. PARANÁ. Matinhos (N.; 25°46.4'S, 48°30.8'W; 3 m; beach/estuary), 9 Apr 2010, D. and W. N. Mathis (1♂; USNM); Paranaguá (Rio Itiberê; 25°31.4'S, 48°30.3'W; 3 m), 23 Jan 2010, D. and W. N. Mathis (1♀; DZUP).

Distribution.

Neotropical: Brazil ( Paraná, São Paulo).

Etymology. The specific epithet, austra, is of Latin derivation and means southern, referring to the distribution of this species in the Southern Hemisphere.

Remarks.

This species differs from congeners in the galapagos group in structures of the male terminalia, especially the shape of the surstylus (see figures and description above). The surstylus has a shallow, ventral bifurcation, somewhat like Nocticanace wirthi , but is more narrowly developed, like Nocticanace panamensis . The anteroventral surstylar lobe is slightly longer than the posterior lobe.