First records of Elachistinae are given from Thailand. Ten species of Elachistinae are reported, eight of which are described as new: Urodeta longa Sruoga & Kaila sp. nov., Elachista buszkoi Sruoga & Kaila sp. nov., E. oryx Sruoga & Kaila sp. nov., E. pellineni Sruoga & Kaila sp. nov., E. capricornis Sruoga & Kaila sp. nov., E. phichaiensis Sruoga & Kaila sp. nov., E. loeiensis Sruoga & Kaila sp. nov. and E. siamensis Sruoga & Kaila sp. nov. The new species are diagnosed and illustrated with photographs of the adults and genitalia. One species remains unidentified to species level.

The species of the Elachista bedellella group with their male genitalia similar with those of E. graeca Parenti, 2002 and E. rudectella Stainton, 1851 are treated. The species share the presence of a cornutus in the male vesica. We restrict species here treated further by the shape of the juxta lobes. The species assemblage considered here apparently does not form a monophylum. The rationale is to narrow down the large group of unrevised species to more manageable units using distinctive characters. Known and named species close to the ones treated here are included in the diagnoses. Twelve species are here treated in detail, five of which are described as new: Elachista belona Kaila & Sruoga, sp. nov. (Russia: Tuva), E. granicorna Kaila & Sruoga, sp. nov. (Tajikistan), E. lagotara Kaila & Sruoga, sp. nov. (Turkmenistan), E. phantasma Kaila & Sruoga, sp. nov. (Kyrgyzstan) and E. scolopsa Kaila & Sruoga, sp. nov. (Lebanon). The females of E. multipunctata Sruoga, 1990, E. graeca Parenti and E. derbendi Parenti, 1981 are described for the first time.

Seven species of Opostegidae are reported from the Himalaya:Opostegoides pelorrhoa (Meyrick, 1915), Pseudopostega frigida (Meyrick, 1906), P. nepalensis Puplesis & Robinson, 1999, P. zelopa (Meyrick, 1905), Pseudopostega brevicaudata Remeikis & Stonis, sp. nov., Opostega chalcophylla Meyrick, 1910 and one documented but left unnamed Opostegoides species. Genital structures of all species treated herein are illustrated with photographs for the first time.

Six species of Elachistinae are newly reported from Nepal, four of which are described as new: Elachista conspecta sp. nov., E. marginata sp. nov., E. minor sp. nov. and E. simulans sp. nov. The new species are diagnosed and illustrated with photographs of the adults and genitalia. E. siamensis Sruoga & Kaila, 2019 and E. kurokoi Parenti, 1983 are recorded for the first time in Nepal.

Neotropical species of the Elachista praelineata species group are reviewed. Five species are recognized in the Neotropics. A new species, Elachista stonisi sp. nov., and female of E. albisquamella Zeller, 1877 are described and illustrated with photographs of the adults, some of the immature stages, female genitalia, and leaf mines. The female of E. lata Sruoga, 2010 is associated with the male based on morphology and the comparison of partial mitochondrial COI sequences. Identification keys to the Neotropical species of E. praelineata species group, based on male and female genitalia, are provided.

No Elachistinae have ever been recorded from Kenya. Here, we present nine taxa, including the descriptions of eight new species: Elachista brevis sp. n., E. kakamegensis sp. n., E. longispina sp. n., E. planca sp. n., Perittia falciferella sp. n., P. gnoma sp. n., P. spatulata sp. n., and P. tantilla sp. n. The new species are diagnosed and illustrated with drawings and photographs of the adults and genitalia. Elachista chelonitis Meyrick is reported for the first time from Kenya. The genus Cleroptila Meyrick is considered to be a synonym of Elachista Treitschke (syn. n.) and Gautengia Kemal & Koçak a synonym of Perittia Stainton (syn. n.). A checklist of Afrotropical Elachistinae is presented.