Diamesa permacra (Walker, 1856)

(Fig. 1 C, D)

The species can be easily identified on the basis of the shape of the aedeagal lobe bearing only fine spines at apex (Fig. 1 C, D). There is an old drawing of this species (Pagast 1947), and the most recent ones are in Serra-Tosio (1971b). In the paper with the original description of D. thomasi Serra-Tosio, 1970 (the dampfi group), some other diagnostic details are also provided.

In Italy, only an adult male associated to pupal exuviae was collected in Acqualba stream in 1978 (Prealps, NO). Larvae and pupal exuviae cannot be separated from D. dampfi; the larvae and pupae recorded in few localities in Prealp springs (Rossaro & Lencioni 2015a, b) probably belong to D. permacra .