Genus Microptila Ris

Microptila Ris 1897, 416–418. Type species Microptila minutissima Ris, by monotypy.

Adult (modified after Marshall 1979). Head with 3 ocelli but no setal warts (Fig. 1 A). Antenna 18–25 segmented. Maxillary palpi each 5-segmented, 2 basal segments short, other segments cylindrical; labial palpi each 3- segmented, basal segment short, other segments cylindrical. Pronotum with pairs of round mesal and round lateral warts; mesoscutellum reversed triangular and metascutellum triangular (Fig. 1 A). Wings long, apically acuminate, length of each forewing 1.5–3.0 mm. Spur formula 0, 3, 4.

Male genitalia simple: Segment IX large with anterior and posterior excisions dorsally and ventrally; tergite X membranous lobe; subgenital plate elongate; inferior appendages elongate caudally; phallus slender and long, tapering to pointed apex in some species, with short spiral titillator in some species.

Larva. Known only for a European species, Microptila minutissima Ris 1897 (Graf et al. 2004; Waringer & Graf 2011). The larva is mainly characterized as follows: Tibial process of foreleg with pinnate spines, abdomen slightly flattened laterally with dorsal sclerite on segment I (hardly visible with transmitted light under compound microscope, visible using scanning electron microscopy) but without caudal filament on segment IX or X; cases purse-shaped, constructed largely of silk with sparse filamentous algae.

Habitat. Adults of most species are found near hygropetric zones.

Japanese name. Keshi-himetobikera-zoku.