Genus Ditrigona Moore, 1888

Ditrigona Moore, 1888: 258. Type species: Urapteryx triangularia Moore, 1867.

Leucodrepana Hampson, 1893: 333. Type species: Leucodrepana idaeoides Hampson, 1892.

Leucodrepanilla Strand, 1911: 198. Type species: Corycia sacra Butler, 1878.

Auzatella Strand, 1917: 148. Type species: Auzata micronioides Strand, 1917.

Thaleridia Moore, 1888: 266. Type species: Thaleridia pruinosa Moore, 1888.

Generic characters.

The generic characters of Ditrigona and its differentiation from related genera are detailed in Wilkinson (1968) and Jiang and Han (2019).

Distribution.

The species of Ditrigona are mainly distributed in the Oriental region.

Ditrigona derocina species group

Wilkinson (1968) placed three species in the Ditrigona derocina species group: Ditrigona derocina (Bryk), Ditrigona diana Wilkinson, and Ditrigona pruinosa (Moore). The two former species have been recorded in China, and a further species, Deroca crystalla Chu & Wang, 1987 is newly placed in this species group in this work.

Species of the Ditrigona derocina species group are characterized by unipectinate antennae and semi-transparent wings. In the male genitalia, the Ditrigona derocina species group is unusual in Ditrigona in having sclerotization of the vinculum, and a quite long and narrow aedeagus. The eighth sternite is distinguished by large and curved octavals, and the tergite protrudes strongly. The female genitalia are characterized by having a very long ductus bursae, an ostial plate, an accessory sac and a long and narrow signum.