The Korean species of Nemoura belong to several different groups. Males of some, especially N. despinosa and N. geei, are readily identified from the excellent illustrations in synopses of the Russian fauna (Zhiltzova 2003, Teslenko & Zhiltzova 2009).
Several new species were discovered in a group including also Arctic or circumpolar species (for example, N. arctica Esben Petersen, N. sahlbergi Morton, N. viki Lillehammer, N. trispinosa Claassen). Because of resemblances in shape of paraprocts and cerci structural details of the epiproct are particularly important but were so far not described in all. The caudal view of the cercus apex provides useful supplementary information to separate the species. It should be remembered that in species whose apical epiproct sclerite is semi-erect and oriented essentially in the sagittal plane the sclerite may look very different, depending on the degree of flattening in microscope preparations.
1 The specimen was cleared in hot KOH. It could be that folds subdividing the lateral sclerites supporting the funnel-shaped structure are an artifact caused by this treatment. The female of A. denstigris was cleared in cold KOH.
Most females in this group can at best be identified tentatively. Females definitely associated with males of the new species are not available. Females in the studied collection remain unidentified and are not recorded.