Polyamia (Polyamia) choromorica sp. n.

(Figs 5–6)

Length. Male: 3.0– 3.1 mm; female: 3.2–3.6 mm.

Coloration and morphology. Ground colour pale brownish marked with brown, fuscous (Fig. 5A–C). Crown white with brown, fuscous marks. Pronotum with small paired fuscous spots anteriorly and six longitudinal brown stripes. Mesonotum and scutellum with fuscous marks (Fig. 5A–B). Face mostly dark brown, with paired white arcs (Fig. 5D). Forewing pale brownish, veins white, cell borders dark brown (Fig. 5A–C). Mesosternum dark brown. Femora and tibiae with fuscous marks (Fig. 5C–D).

Head wider than pronotum, anterior margin distinctly angulate in dorsal view. Crown longer than distance between eyes (Fig. 5A–B). Clypeal sulcus absent. Anteclypeus tapering to apex, extending beyond normal curve of genae. Lorum semicircular, narrower than anteclypeus, well separated from lateral margin of face (Fig. 5D). Pronotum slightly longer than vertex or nearly as long as vertex (Fig. 5A–B). Forewing exposing apex of pygofer or not, with numerous extra crossveins, especially in clavus (Fig. 5A–C).

Male genitalia. Pygofer lobe long, apex rounded, with numerous macrosetae in distal half (Fig. 6A–B). Valve angulate caudally. Subgenital plate 3x length of valve, subtriangular, lateral margin incurved, apex acute, with macrosetae arising laterally (Fig. 6C). Style with short articulatory arm; preapical lobe rectangular; apophysis digitate, apex acute, slightly laterally curved (Fig. 6D). Connective slightly shorter than aedeagus. Aedeagus with shaft in lateral view moderately long and slender, slightly tapered from base to apex and curved slightly dorsad, apex obliquely tapered; in ventral view slightly tapered, apex truncate with pair of small lateral projections (Fig. 6E–F).

Female. Sternite VII with posterior margin undulate, without posteriolateral lobes (Fig. 5E).

Material examined. Holotype: ♂, Argentina: Tucumàn, 23 rd km W Choromoro, 1180 m, 26°23′41"S, 65°31′19"W, 20 January 2008, C.H. Dietrich, vacuum, AR29–1 (MLP) . Paratypes: 2♂, 2♀, same data as holotype (INHS) .

Remarks. This species runs to P. (P.) randa DeLong & Thambimuttu (couplet 1) in the key of Sinada and Blocker (1994) and is similar to that species, recorded from Mexico and Panama, in form and coloration, including structure of the male genitalia and female abdominal sternite VII. Polyamia (P.) choromorica sp. n. is easily distinguished by the much less strongly curved aedeagal shaft, the vestigial dorsal aedeagal apodeme, and lack of a distinct emargination at the shaft apex. Polyamia (P.) randa DeLong & Thambimuttu has the distal half of the aedeagal shaft oriented perpendicularly to the basal part and connective in lateral view.

Distribution. Argentina

Etymology. The specific epithet is based on the type locality.