Acostatrichia fimbriata Flint 1974

Santos, Allan Paulo Moreira, 2020, A review of the Neotropical microcaddisfly genus Acostatrichia Mosely, 1939 with description of a new species from Brazil (Trichoptera: Hydroptilidae: Leucotrichiinae), Zootaxa 4755 (2), pp. 201-230 : 216-217

Acostatrichia fimbriata Flint 1974

Figs. 9 , 16

Acostatrichia fimbriata Flint 1974:54 . Figs. 108-110, male; type locality: Surinam: Coppename River, Raleigh Falls; type depository: RNH.

Redescription. Length from front of head to tips of folded forewings 2 mm (n = 1). General color, in alcohol, light brown. Head unmodified. Ocelli 3. Antennae broken. Forewings each with costal vein simple, unmodified.Abdominal segment VII bearing very long ventromesal process, with fimbriate and capitate apex ( Fig. 9A ). Segment VIII shorter dorsally than ventrally; in ventral view, posterior margin of sternum truncate; with pair of long ventrolateral processes, each bearing acute projection on median area and fimbriate projection at apex; tergum with scattered setae. Segment IX mostly within segment VIII, ventrally open; without dorsolateral processes. Preanal process obliquely truncate and bearing very long setae ( Fig. 9A ). Inferior appendages fused with each other as plate, with shallow U-shaped incision on posterior margin in ventral view ( Fig. 9B ); with pair of very long digitate lateral processes rising from apex ( Fig. 9B ); in lateral view, upturned. Subgenital plate, in ventral view, broad and rounded at apex; in lateral view, slightly downturned ( Fig. 9A ). Tergum X membranous, bilobed, both lobes rounded in dorsal view. Phallus tubular basally, bearing midlength complex, with dorsal window, basal loop indistinct; apical portion with pair of long internal spines.

Material examined. PARATYPE: Surinam, Coppename River, Raleigh Falls , 9 July 1963, D.C. Geijskes leg., 1 male, partially damaged ( NMNH).

Remarks. This species is known from the male type specimens from Suriname. The paratype studied is partially damaged and missing some genital structures, preventing preparation of a complete set of illustrations. The description provided above was made based on this specimen and on the original description. Acostatrichia fimbriata is closely related to A. brevipenis as mentioned by Flint (1974). This species is easily distinguished from A. brevipenis and other Acostatrichia species by the ventrolateral processes of segment VIII each having a dorsal acute projection and a fimbriate apex.

Distribution. Suriname ( Fig. 16 ).

Figures

FIGURE 9. Acostatrichia fimbriata Flint 1974, paratype male, genitalia. 9A, left lateral (segment VIII was missing in the specimen and the dashed line is based on the illustration by Flint 1974); 9B, inferior appendages and posteroventral margin of segment IX, ventral. Scale bar = 0.1 mm.

FIGURE 16. Distribution map of the Acostatrichia species in South America, based on material examined here and previously published records. When latitude and longitude were not available, an approximate location was used. Circle, species in the Acostatrichia plaumanni Group; square, species in the Acostatrichia brevipenis Group; triangle, species in the Acostatrichia cerna Group.