Pseudopostega acrodicra Davis & Stonis 2007

Pseudopostega acrodicra

ADULT. Figure 214. Length of forewing 5.0–5.6 mm. Small, mostly white moth with white forewings marked with a relatively large, often triangular, dark brown to fuscous spot at distal one-fourth of costa, 2 faint, light brown, subapical costal strigulae, and a small, dark brown to nearly black apical spot. Male gnathos with apex of caudal lobe minutely forked; basal fold slender, slightly arched (Figure 377). Papillae anales of female fused into a single, stout, moderately long setose lobe (Figure 481).

Head: Vestiture white. Scape white; flagellum light brown, 74–76-segmented. Palpi cream, lightly irrorated dorsally with brown scales on maxillary palpus, more heavily irrorated dorsally and laterally with brown on labial palpus.

Thorax: White; tegula with dark brown spot on anterior margin. Forewing white with a relatively large, often triangular, dark brown to fuscous spot at distal one-fourth of costa and 2 faint, light brown, subapical costal strigulae traversing apical cilia; first strigula crossing near base of cilia, often with faint suffusion of grayish brown from inner margin over apical area of wing; strigula 2 across middle of cilia, terminating just before small, brown to nearly black apical spot; terminal cilia mostly white, with faint brownish suffusion along dorsal margin; venter of forewing light brown except for basal, subhumeral white area. Hindwing and cilia light brown dorsally and ventrally except for white suffusion at base. Legs mostly white to cream; foreleg with dorsal surfaces heavily suffused with dark brown; tarsomeres mostly brown ventrally; midleg with tarsomeres ringed with brown; tarsomeres of hindleg more lightly ringed with brown dorsally, mostly cream ventrally.

Abdomen: Brown dorsally, white to cream ventrally.

Male Genitalia: Figures 377. Socii a pair of relatively small, rounded, setose lobes widely separated by a distance ~0.7× length of cucullar lobe; caudal rim of tegumen concave, broadly V-shaped. Vinculum broad; anterior margin subtruncate to slightly concave. Base of gnathos broad, abruptly narrowing posteriorly to a moderately long, slender, caudal process with a slightly broader, short, furcate apex; anterior margin slightly concave, with a slender, slightly arched, basal fold. Valva with an elongate cucullar lobe ~0.6× length of genital capsule; bearing a pectinifer consisting of a single row of ~46–48 blunt spines; terminal apex of cucullar lobe extended slightly as a roughly tuberculate, narrowly rounded lobe; base of pedicel broad, approximately one-third length of cucullar lobe; valva elongate, length along sacculus ~0.75× length of genital capsule; saccular lobe moderately slender, tapering to subtruncate, setose apex; basal process of valva tapering to acute apex, exceeding length of costal lobe. Juxta undeveloped.

Female Genitalia: Figures 480, 481. Apex of abdomen subacute, with two large, closely aligned setose lobes. Each posterior apophysis fused most its length, slender and moderately long, length ~5.5× length of papillae anales. Papillae anales fused into a single, moderately long, stout, setose lobe; setae ~0.32× length of apophysis. Vestibulum relatively narrow, membranous. Ductus bursae with a small concentration of pectinations aligned in transverse rows of usually 3–7 minute spicules; a similar, longer zone of pectinate spicules located more anteriorly at junction of corpus bursae. Corpus bursae slightly enlarged anteriorly, with a dense, U-shaped band of relatively large, external tubercles. Ductus spermathecae ~0.5× length of bursa copulatrix; membranous outer canal broadly inflated, ~0.85× length of entire duct; inner canal long, slightly sinuous, with about 3–4 small, terminal convolutions abruptly enlarging to form a bilobed, tubular vesicle.

LARVA AND PUPA. Unknown.

HOLOTYPE. ♂; BRAZIL: MINAS GERAIS: Unaí, 700 m: 1 ♂, 3 Nov 1983, V. O. Becker (VOB).

PARATYPES. BRAZIL: MINAS GERAIS: Unaí, 700 m: 3 ♂, 27 Sep 1983, 1 ♂, 16 Oct 1988, 7 ♂, 1 ♀, 1 UNK, 7 Nov 1982, V. O. Becker, slides USNM 28653, 31961, 32870, (USNM, VOB). MATO GROSSO: Unai, 700 m, 9 Nov 1983, V. O. Becker (VOB).

HOST. Unknown.

FLIGHT PERIOD. Adults have been collected from September to November.

DISTRIBUTION. (Map 15) Known only from the type locality in south-central Brazil.

ETYMOLOGY. The species name is derived from the Greek akron (tip, end) and dikros (forked, cloven) in reference to the small, apical furcation of the caudal lobe of the male gnathos.

DISCUSSION. This species is closely allied to another Brazilian species, P. caulifurcata, as evidenced by their similar wing pattern and male genital morphology. The male of P. acrodicra differs from the latter in possessing a gnathos with a broader base and relatively shorter caudal lobe. The most significant distinction between the males of these two species is the longer sacculus of acrodicra (nearly 0.7× length of genital capsule), and in particular the longer, more robust saccular lobe. The papillae anales of female acrodicra are unusual in consisting of a single, fused lobe, similar to that occurring in P. elachista and most P. venticola. The female of caulifurcata is unknown.

Pseudopostega acrodicra is a moth of the family Opostegidae. It was described by Donald R. Davis and Jonas R. Stonis, 2007. It is known from south-central Brazil.

The length of the forewings is 5-5.6 mm. Adults have been recorded from September to November.