LAUSR

Abstract The taxonomy of South American Scythrididae (Lepidoptera: Gelechioidea) is revised, based on external morphology, genitalia, male abdominal segment VIII, and DNA barcodes using genetic distances, BINs, and a tentative molecular phylogeny. Data include both historical and fresh specimens from Argentina, Brazil, Colombia, Chile, Ecuador, Paraguay, and Peru. Thirty-four species are recognised as valid, and the fauna classified in three genera. Type specimens and morphology of all species are described and figured in detail. DNA barcode sequences of the COI gene were successful for 22 species, the average genetic divergence between species being 5.1%. A key to Neotropical Scythrididae species is provided, based on the male genitalia and abdominal segment VIII, which show most and easily accessible interspecific differences. Our study revealed that the Scythridae fauna of South America is more or less completely unknown. As a result, 22 new species are described, increasing the number of South American Scythrididae species from 13 to 34. All new species are authored by Kari Nupponen (incertae sedis means the genus combination is uncertain and needs further research, country of the type locality is given in parentheses): Rhamphurasubdimotasp. nov. (Argentina), R.pozohondaensissp. nov. (Argentina), R.spiniuncussp. nov. (Argentina), R.angulisociellasp. nov. incertae sedis (Argentina), R.curvisociellasp. nov. incertae sedis (Argentina), R.tetrafasciellasp. nov. incertae sedis (Argentina), Landryiaankylosauroidessp. nov. incertae sedis (Argentina), L.chilensissp. nov. incertae sedis (Chile), Scythrisdirectiphallellasp. nov. (Argentina), S.furciphallellasp. nov. (Argentina), S.manchaoensissp. nov. (Argentina), S.salinasgrandensissp. nov. (Argentina), S.angustivalvellasp. nov. (Argentina), S.caimancitoensissp. nov. (Argentina), S.lequetepequensissp. nov. (Peru), S.sanfriscoensissp. nov. (Argentina), S.tigrensissp. nov. (Argentina), S.bicoloristrigellasp. nov. incertae sedis (Argentina), S.saldaitisisp. nov. incertae sedis (Argentina), S.wikstromisp. nov. incertae sedis (Argentina), S.andensissp. nov. incertae sedis (Argentina), S.mendozaensissp. nov. incertae sedis (Argentina). The following new combinations are proposed: Scythrisdepressa Meyrick, 1931 and Scythrisdimota Meyrick, 1931 are transferred from Scythris Hübner, 1825 to Rhamphura Landry, 1991 comb. nov. Three species classified in Scythris earlier are now classified as Scythris (incertae sedis): Scythrisdividua Meyrick, 1916, S.medullata Meyrick, 1916 and S.notorrhoa Meyrick, 1921. The taxon Syntetrernisneocompsa Meyrick, 1933, recently classified in Scythrididae: Scythris, is excluded from Scythrididae and it is now classified in Cosmopterigidae incertae sedis.