First male description of Urodeta longa Sruoga & Kaila, 2019 from Thailand with identification keys to Asian species of Urodeta Stainton, 1869 (Lepidoptera, Elachistidae, Elachistinae)

A male of the little-known species Urodeta longa Sruoga & Kaila, 2019 is described for the first time based on material collected in northern Thailand. The species is diagnosed based on characters found in the habitus and genitalia, which are illustrated in detail. Conspecificity of male and female specimens is confirmed by DNA barcodes.

Identification keys to all known Asian species of the genus Urodeta Stainton, 1869, based on male and female genitalia, are provided. Exceptionally high intra-generic barcode divergence among Urodeta species is reported.