Pseudopostega acuminata Davis & Stonis 2007

Pseudopostega acuminata

ADULT. Figures 176. Length of forewing 3.1–3.3 mm. Small, mostly white moth with white forewings marked with a moderately large, broadly triangular, fuscous spot near distal third of costa, a pair of slender, fuscous, subapical strigulae, the most apical of which is more faint, a slender, fuscous, tornal strigula, and a small, oblong, dark fuscous apical spot. Male with gnathos broadly triangular, tapering to slender, elongate, strongly reflexed caudal lobe; basal fold narrow, with slightly convex caudal margin (Figures 326, 327). Female unknown.

Head: Vestiture white. Scape white. Flagellum golden brown dorsally, paler ventrally, ~44-segmented. Maxillary palpus white. Labial palpus white, with brownish suffusion laterally and dorsally.

Thorax: White. Forewing almost entirely white, with a broadly triangular, fuscous spot at distal 2/5–1/3 of costa, a dark fuscous, subapical costal strigula from costal subapex to brownish suffusion immediately basal to oblong, fuscous apical spot; strigula 2 fuscous, short, and poorly preserved in specimens examined but curving across apex of wing around apical spot; tornal strigula fuscous, shortly extended below apical spot; terminal cilia variable, white around apex and tornus, becoming light brown immediately above apical spot and immediately distad to terminal strigula and then brown apically and along dorsal margin; venter of forewing light brown with white patch over base of wing. Hindwing and cilia light brown dorsally and ventrally. Legs mostly cream; foreleg heavily suffused with dark gray dorsally from coxa to end of tarsi; mid- and hindlegs with dorsal base of tarsomeres banded with gray.

Abdomen: Grayish brown dorsally, white ventrally.

Male Genitalia: Figures 326, 327. Socii a pair of moderately long, rounded, setose lobes, widely separated by a distance ~0.9× length of cucullar lobe; caudal rim of uncus shallowly concave. Vinculum moderately broad, narrowing to a slightly concave to truncate anterior margin. Gnathos broadly triangular, tapering abruptly to form a slender, elongate, strongly curved dorsally, caudal lobe; apex of lobe acute; anterior margin of gnathos shallowly concave, slightly swollen at middle; basal fold narrow, moderately arched (Figure 326). Valva with a relatively short cucullar lobe ~0.3× length of genital capsule, bearing a pectinifer consisting of ~28–29 blunt spines; distal apex of cucullar lobe extended; pedicel moderately broad, ~0.2× length of cucullar lobe; length of valva along sacculus ~0.65× length of genital capsule; saccular lobe moderately stout, elongate, gradually tapering to a narrow, smoothly rounded apex bearing ~7–8 small setae; basal process of valva tapering to acute apex, slightly exceeding length of slender costal process. Juxta undeveloped.

FEMALE, LARVA AND PUPA. Unknown.

HOLOTYPE. ♂; ARGENTINA: TUCUMáN: 11 km S Tacanas, 28 km WSW Trancas, sta. 28, 800 m: 16–17 Dec 1995, Neth. Ent. Exp. N-Arg., slide DRD 4135 (RMNH).

MATERIAL EXAMINED. VENEZUELA: MéRIDA: Mucuy Fish Hatchery, 7 km E Tabay, 6600 ft [~2000 m]: 1 ♂, 10–13 Feb 1978, J. B. Heppner, slide USNM 32968 (USNM).

HOST. Unknown.

FLIGHT PERIOD. Adults have been collected in February (Venezuela) and April (Argentina).

DISTRIBUTION. (Map 7) Known from only two widely disjunct localities in northern Argentina and northwestern Venezuela.

ETYMOLOGY. The species name is derived from the Latin acuminatus (pointed, sharpened), in reference to the long, slender, acute caudal lobe of the male gnathos.

DISCUSSION. The holotype male of P. acuminata from Argentina is characterized by the long, slender, dorsally recurved caudal lobe of the gnathos, broad basal fold with a small median swelling, and broad, slightly concave anterior margin of the vinculum. A single male from Venezuela may represent a disjunct population of this species, but the genitalia differ from the holotype in possessing a slightly more narrow, truncate vinculum and basal fold without a noticeable median enlargement. For these reasons this specimen has not been considered a paratype.

Pseudopostega acuminata is a moth of the family Opostegidae. It was described by Donald R. Davis and Jonas R. Stonis, 2007. It is known from northern Argentina and north-western Venezuela.

The length of the forewings is 3.1–3.3 mm. Adults have been recorded in February (in Venezuela) and April (in Argentina).