Pseudopostega latisaccula Davis & Stonis 2007

Pseudopostega latisaccula

ADULT. Figure 161. Length of forewing 2.0–2.4 mm. Small, mostly white moth with white forewings typically marked by a small, elongate, dark brown to fuscous dorsal spot midway along hind margin, an elongate, dark brown to fuscous spot near apex of costa obliquely slanted to termen, and a single, fuscous, subapical costal strigula; apical spot absent. Male with saccular lobe of valva broadly expanded, round; gathos narrow, tapering slightly to an indistinct, stout, subacute caudal lobe; basal fold absent (Figure 302). Papillae anales of female a reduced, widely separated pair of setose lobes; eighth abdominal segments with elongate dorsal and ventral paired pseudapophyses (Figures 444, 445).

Head: Vestiture white. Scape white; flagellum pale brown to brown, ~44–52-segmented. Maxillary palpus white to cream. Labial palpus white, suffused with brown laterally.

Thorax: White; tegula entirely white. Forewing white, marked by a small, elongate, dark brown to fuscous dorsal spot midway along hind margin, an elongate, dark brown to fuscous subterminal spot near apex of costa obliquely slanted to termen, and a single, fuscous, subapical strigula extending across base of cilia from costa often to tornus; apical spot absent; terminal cilia brown beyond strigula, then lighter brown along tornus and outer dorsal margin; venter of forewing brown except white at base over humeral area. Hindwing and cilia brown dorsally and ventrally except for white suffusion at base. Legs mostly cream; foreleg with lateral and dorsal surfaces brown; midlegs with terminal three tarsomeres mostly brown.

Abdomen: Light brown dorsally, white to cream ventrally. Sternum 7 of female relatively elongate, extending well caudad of papillae anales; both tergum 7 and sternum 7 with a pair of long, slender, flattened pseudapophyses; tergal pseudapophyses with anterior end strongly curved mesad.

Male Genitalia: Figures 302, 303. Socii a pair of very small, rounded, setose lobes, narrowly separated a distance about equal to width of gnathos base; caudal rim of uncus subtruncate. Vinculum elongate, rather abruptly constricted anteriorly beyond bases of valvae; anterior margin narrow, slightly round to subtruncate. Gnathos elongate, narrow, tapering slightly to a slender, round apex; anterior margin slightly concave; basal fold undeveloped. Valva with a large, semicircular shaped cucullar lobe ~0.4× length of genital capsule, bearing a pectinifer consisting of 42–46 blunt spines; pedicel strongly curved mesad, slender, elongate, width ~0.08× length of cucullar lobe; valva elongate, length along sacculus ~0.7× length of genital capsule; saccular lobe greatly enlarged as a broad, flattened, rounded lobe, extending well beyond apex of pedicel and either completely or nearly across cucullar lobe (Figure 302); basal process of valva relatively short, acute, terminating near apex of costal process. Juxta indistinct, membranous.

Female Genitalia: Figures 444, 445. Abdomen tapering to a slender, slightly cleft, setose apex. Each posterior apophysis fused for most its length, very slender and long. Papillae anales a pair of widely separated, small, rounded lobes connected by a slender, broadly U-shaped ninth tergite. Vestibulum membranous. Ductus bursae elongate, equaling length of corpus bursae, densely covered internally with pectinations consisting of short rows of 2–5 minute spicules; these becoming more fused into longer, dentate, transverse pectinations near junction with the corpus bursae; beyond this typically curved junction zone, pectinations gradually disappearing further into elongate corpus bursae; signum consisting of a long, slender, inverted U-shaped, nearly circular band of minute, conical to truncate, external tubercles. Ductus spermathecae short, approximately the length of ductus bursae; outer membranous canal reduced in diameter, closely adhering to tubular inner canal; latter usually undergoing 4–5 convolutions before enlarging to form a terminal, sigmoid vesicle.

LARVA AND PUPA. Unknown.

HOLOTYPE. ♂; DOMINICA: 2 mi [3.2 km] NW Pont Casse, 16 May 1965, D. R. Davis (USNM).

PARATYPES. DOMINICA: 0.4 mi [0.64 km] NW Pont Casse: 2 ♂, 2 ♀, 6 May 1964, O. S. Flint (USNM). 1.5 mi [2.4 km] NW Pont Casse: 7 ♂, 13 ♀, 1 UNK, 3 Apr 1965, D. R. Davis, slides USNM 16351, 16352 (SEM), 16353, 16354 (SEM), 32424, 32483 (USNM). 2 mi [3.2 km] NW Pont Casse: 3 ♀, 1 UNK, 20 Apr 1965, 4 ♀, 2 May 1965, 1 ♀, 5 May 1965, 1 ♀, 16 May 1965, 1 UNK, 17 May 1965, 2 UNK, 18 May 1965, 1 UNK, 25 May 1965, D. R. Davis, slides USNM 28764, 28765 (USNM). 5 mi [8 km] E Pont Casse: 1 ♂, 27 Jan 1965, J. F. G. & T. M. Clarke (USNM). Central Forest Reserve: 1 ♂, 3 ♀, 6 UNK, 3 May 1965, D. R. Davis, slide USNM 28763 (USNM). Clarke Hall: 2 ♂, 2 ♀, 23 Apr 1964, 1 ♂, 25 Apr 1964, O. S. Flint (USNM). Pont Casse: 1 ♂, 3 ♀, 6 Apr 1965, D. R. Davis (USNM). Rosalie: 1 UNK, 15 Jun 1965, D. R. Davis (USNM). Trafalgar: 1 ♂, 21 May 1965, D. R. Davis (USNM). PUERTO RICO: Carite, 500 m: 1 ♂, 17 Aug 1987, V. O. Becker, slide USNM 32478 (USNM). Centro Vacacional, Monte del Estado, nr. Maricao, 650 m: 2 ♂, 1–9 Mar 1971, C. F. Kimball, slide USNM 32738 (USNM).

HOST. Unknown.

FLIGHT PERIOD. This species probably flies throughout most of the year with records for January, March–June, and August reported.

DISTRIBUTION. (Map 6) Probably widespread in the Greater Antilles but currently known only from Dominica, where it was found to be common, and Puerto Rico.

ETYMOLOGY. The species name is derived from the Latin latus (broad, wide) and sacculus (little sac) in reference to the diagnostic, greatly enlarged saccular lobe of the male valva.

DISCUSSION. Pseudopostega latisaccula was the most common opostegid encountered during the three-year Bredin-Archbold Smithsonian Biological Survey of Dominica. The females are unusual in possessing the most slender, elongate ovipositor (including abdominal segments 7 and 8) known for the Opostegidae. This specialization suggests a modification in ovipostion behavior that may involve depositing eggs in a more concealed site than normal. The paired pseudapophyses within segment 7 may have developed as additional support for this prolongation.

The triangularis group

Males of the triangularis group are characterized by a generally triangular gnathos (viewed ventrally), which gradually tapers caudally to either an acute apex, or to a more attenuated, slender, caudal lobe. The valvae are moderately long (length along the sacculus ranging from ~0.5–0.7× the length of genital capsule), with well-developed saccular lobes. A juxta is usually absent.

Pseudopostega latisaccula is a moth of the family Opostegidae. It is probably widespread in the Greater Antilles but currently known only from Dominica (where it is common) and Puerto Rico.

The length of the forewings is 2–2.4 mm. Adults are mostly white. Adults have been collected throughout most of the year with records for January, from to March to June and August.