A new genus and new species of valvatiform rissooid from continental Greece are described. The snail has a combination of anatomical characters not previously found in any known rissooid genus. It can be differentiated from Daphniola and Pseudoislamia, the other valvatiform hydrobiid genera known from Greece, by microsculpture of transition between protoconch and teleoconch, mantle and head pigmentation, lack of ctenidium, overall shape and pigmentation of penis, number and position of penial lobes, and the relative size of the seminal receptacles; and by shell aperture contour and number and position of penial lobes, respectively. Analysis of partial sequences of COI and 18S place it in Hydrobiidae, Sadlerianinae, with Radomaniola/Anagastina as sister clade, but well removed from the other valvatiform genera.

Key words: Balkans, DNA, molecular phylogeny, anatomy, taxonomy, freshwater, Hydrobiidae, Sadlerianinae; Europe, taxonomy; Gastropoda