Mesoptila Meyrick, 1891

Mironov, Vladimir G. & Galsworthy, Anthony C., 2012, A generic level review of Eupithecia Curtis and some closely related genera based on the Palaearctic, Nearctic and Oriental fauna (Lepidoptera, Geometridae, Larentiinae), Zootaxa 3587, pp. 46-64 : 50-51

Mesoptila Meyrick, 1891

Mesoptila Meyrick, 1891 , Proceedings of the Linnaean Society of New South Wales, (2) 5, 793 (key), 794. Type species: Mesoptila compsodes Meyrick , by original designation.

Emmesocoma Warren, 1907, Novitates zoologicae, 14 (1), 155. Syn. n. Type species: Emmesocoma deviridata Warren , by original designation.

Diagnosis. Differing externally from Eupithecia by the central tuft of erect scales in the longitudinally elongate fore wing disc. The male abdomen has long and narrow apodemes on the second tergite, while those in Eupithecia are short and broad. The male genitalia are distinguished from Eupithecia by the unusually narrow, usually curved, valve with a broadened basal lobe to the sacculus bearing a tuft of long setae, by the replacement of the normal papillae on the anterior arms of the labides by a narrow membranous cushion on the ventral surface bearing a row of setae, and by the more elongate shape of the juxta. The female genitalia have no significant differences from those of representatives of the genus Eupithecia .

Description. Adults (figs 1–3). Labial palpi with separate tufts of scales at the base under the eyes. Frons with a short tuft of tight-fitting scales directed forward. Head with double collar of scales behind eyes; distance between scapes of antennae short. Antennae filiform in male and female. Metathorax without crests of scales. Hind leg with two pairs of tibial spurs. Apodemes of the second tergite extremely long and narrow (fig. 31). Venation of fore wing: R1 long, not uniting or anastomosing with Sc; areole without oblique transverse vein; M1 and R2+5 arising separately from cell, a short distance from each other. Venation of hind wing: M3 and CuA1 arising separately from cell (fig. 13). Fore wing relatively narrow and elongate, with almost straight costal margin and narrowly rounded apex, the costal margin with a row of narrow and elongate scales in basal half of fore wing. Pattern in most species very distinct: medial area on the fore wing slightly darker, distinctly bordered by ante- and especially postmedial lines, the latter with a pale external border, and with a patch of protruding black scales on the stalk of the CuA vein; terminal area with distinct light subterminal transverse line; discal dot large, elongate, rather ovate, consisting of an erect black scale-tuft. Hind wing triangular with rounded apex, almost straight terminal margin and right angled tornus; generally paler than fore wing, brownish ochreous, with a much darkened area along the anal margin terminating in a characteristic dark tornal blotch bordered with fine white lines. In one species the upperside pattern is entirely suppressed and replaced with a uniform medium brown, varied only by discal and a few costal spots. Underside of wings pale with distinct but paler transverse postmedial lines and tornal spots, white on the fore wing and black on the hind wing; discal dots not visible. No sexual dimorphism in the size, shape, colouration and pattern of wings.

Male genitalia (figs. 17, 18). Uncus with short but prominent basal lobes, its spine-like apical part slightly broadened near apex, with thin and pointed tip. Anal tube relatively broad, covered with numerous short setae in apical part. Tegumen narrow. Valve elongate and narrow, usually slightly curved; sacculus broadened near vinculum with a tuft of long setae. Vinculum very short and relatively narrow, slightly tapered to apex. Coremata present. Labides short and narrow; anterior arms of labides short with narrow membranous cushions on ventral side, covered with a row of setae; posterior arms with larger setaceous papillae connected with each other at the middle. Juxta shaped like an hour-glass, as in Eupithecia , but more longitudinally elongate. Aedeagus usually slim, shorter than length of valve; ductus ejaculatorius attached to anterior end of aedeagus. Vesica covered with numerous longitudinal striations and dense small teeth, armed with one long and narrow styloid cornutus with lancet-shaped apex. Sternite A8 almost membranous or very lightly sclerotized, with two narrow, apically blunt and slightly broadened arms, connected with each other by a short band at base and divided by a deep membranous hollow.

Female genitalia (fig. 25). Bursa copulatrix membranous, small, almost completely covered with small spines. Ductus bursae not distinguishable. Ductus seminalis slightly broadened at base, attached to posterior part of corpus bursae near colliculum on left side. Colliculum short and narrow. Antrum membranous, long and narrow. Two narrow, sclerotized, band-like branches, slightly broadened to apices, arising from basal parts of anterior apophyses. Tergite A8 elongate, rectangular. Anterior and posterior apophyses narrow, anterior apophyses relatively elongate, posterior apophyses relatively short. Papillae anales small, rounded or slightly elongate, covered mainly with short setae.

Distribution. South and South East Asia, Philippines (Mindanao), Sri Lanka, Bali, Borneo, Sulawesi, New Guinea, Java, Australia, East and South Africa.