Pseudopostega pumila (Walsingham 1914) Davis 1989

Pseudopostega pumila (Walsingham)

Opostega pumila Walsingham, 1914:350.—Davis, 1984:18.

Pseudopostega pumila (Walsingham).—Davis, 1989:77.—Puplesis and Diškus, 2003:418.

ADULT. Figure 227. Length of forewing ~3.2 mm. Small white moth with 3 golden brown, subapical costal strigulae and a fuscous apical spot near apex of forewing.

Map 18. Distribution of New World Pseudopostega brachybasis species group.

Male gnathos with stout caudal lobe terminating in a broadly bilobed apex; basal fold absent (Figure 398). Female unknown.

Head: Vestiture white. Scape white; flagellum ochreous cream dorsally, whitish cream ventrally, ~56-segmented. Palpi whitish cream.

Thorax: White. Forewing white, with very light brownish scales suffused over wing and visible from a certain viewing angle; subapical region of forewing marked with 3 golden brown, subapical costal strigulae; first strigula extending obliquely across wing well before small, fuscous, apical spot; strigula 2 parallel to 1 but shorter and fading to yellowish area before apical spot; strigula 3 short, fading above apical spot, then interrupted above spot before continuing around spot to tornus; terminal cilia cream, otherwise white; venter of forewing yellowish brown. Hindwing whitish cream dorsally and yellowish brown ventrally, except for cream white area at basal 1/6; cilia cream to ochreous cream. Legs ochreous cream with brownish suffusion on tarsi of mid- and hindlegs.

Abdomen: Ochreous cream dorsally, lustrous cream ventrally.

Male Genitalia: Figures 398, 399. Socii a pair of slender, setose lobes moderately widely separated by a distance ~0.35× length of cucullar lobe; caudal margin of uncus rather deeply concave. Tegumen narrow. Vinculum broad, with anterior margin rounded. Gnathos broad at base, consisting of a broad, oval plate that constricts abruptly to form a moderately stout, elongate, caudal lobe terminating in a broadly bilobed apex which curves slightly dorsally; basal fold absent. Valva with elongate cucullar lobe ~0.45× length of genital capsule, bearing a pectinifer consisting of ~38–40 blunt spines; outer apex of cucullar lobe slightly extended, rounded, and setose; Valva moderately long, ~0.65× length of genital capsule; saccular lobe broad, irregularly rounded; basal process of valva relatively short, acute; costal process of valva well sclerotized and equal in length to basal process. Juxta undeveloped.

FEMALE, LARVA AND PUPA. Unknown.

HOLOTYPE. ♂; MEXICO: TABASCO: Teapa, Mar 1918, H. H. Smith, Gdm. Slv. 66772, BMNH slide 29631 (BMNH).

Material Examined. Holotype ♂.

HOST. Unknown.

FLIGHT PERIOD. March (unique record).

DISTRIBUTION. (Map 18) Known only from the type locality in southern Mexico.

DISCUSSION. This species is represented only by the male holotype, which is in good condition. The caudal lobe of the male gnathos in P. pumila superficially resembles that of some species of the divaricata species group (e.g., P. concava, also from Mexico). The gnathi in the latter group, however, do not possess the lateral, lobate expansion present in pumila and in other members of the brachybasis group. The gnathos of pumila differs from that of latiapicula and ecuadoriana in having the apical lobe more divided and in lacking a basal fold.

Pseudopostega pumila is a moth of the family Opostegidae. It was described by Walsingham, Lord Thomas de Grey, in 1914. It is known from Tabasco, Mexico.

The length of the forewings is about 3.2 mm. Adults have been recorded in March.