Orgyarbela, Yakovlev & Zolotuhin, 2020

Yakovlev, Roman V. & Zolotuhin, Vadim V., 2020, Revision of the family Metarbelidae (Lepidoptera) of the Oriental Region. I. Introduction and genera Encaumaptera Hampson 1893, Orgyarbela gen. nov., and Hollowarbela gen. nov., Ecologica Montenegrina 38, pp. 84-101 : 93

Genus Orgyarbela gen. nov.

Type species (here designated): Arbela millemaculata Hampson, 1897 .

Description. Basing on the known material, the genus is strongly sexually dimorphic.

Male. Small species, male fore wing length 9–10 mm. Antenna bipectinate, crest processes three times longer than antenna rod diameter in its medium third. Fore wing narrow, often with fine spotty pattern, hind wing smaller, without pattern. Bunch of very long hairs on tip of abdomen.

Male genitalia. Uncus very robust, strongly expanded towards top, apically with deep semicircular bifurcation; tegumen robust; gnathos arms of medium length; gnathos small; valve short, abdominal edge hypertrophied, strongly sclerotized, small dentate harpe on abdominal edge; juxta cup-like; saccus tiny; phallus short, slightly sharpened apically.

Female (only the female of O. millemaculata is known). Slightly larger than male, colored brightly and lighter. Antenna bipectinate, crest processes approximately equal to antenna rod diameter in its medium third. Pattern of fore wing mottled. Hind wing with longitudinal dark band. Bunch of very long hairs on tip of abdomen. Genitalia not examined.

Diagnosis. The new genus differs from the known Metarbelidae genera in the gracility, dimorphism in color and size, relatively bright coloration of females, the presence of a bundle of very long scales at the apex of the abdomen in both sexes, a very powerful split uncus. The split uncus, the reduced hind wing size and the dimorphism may be considered the autapomorphies of the genus.

The bright color and the extreme rarity of both sexes in collections suggest their daily activity and this may be also a unique autapomorphic feature of this group / genus.

Composition. The new genus includes three species: O. millemaculata ( Hampson, 1897) comb. nov., O. kerri sp. nov. and O. mackwoodi sp. nov.

Distribution. Eastern India, Myanmar and Laos ( Fig. 28 ).

Figures

Figure 28. Distributional map of genera Orgyarbela gen. n. & Hollowarbela gen. n.