ZOOKEYS, cilt.2024, sa.1214, ss.265-279, 2024 (SCI-Expanded)
As part of our detailed study of the Caucasian mayfly fauna, we describe Epeorus ( Cau- casiron) abditus sp. nov., a new species of the genus Epeorus Eaton, 1881, subgenus Caucasiron Kluge, 1997, based on larvae collected in T & uuml;rkiye, Georgia, and Russia. We use several methodological approaches to delimit the new species by analysing COI sequence data and larval morphology. We provide a comparison with related taxa and diagnostic characters allowing determination of the larvae. We also update the identification key for the Caucasian species of E . ( Caucasiron ) with E . (C.) abditus sp. nov. and two recently described species, E . (C.) hyrcanicus Hrivniak & Sroka, 2021 and E . (C.) tripertitus Hrivniak & Sroka, 2022.