Eudontomyzon graecus, a new nonparasitic lamprey species from Greece (Petromyzontiformes: Petromyzontidae)

Abstract

Eudontomyzon graecus, sp. n., a nonparasitic lamprey from Greece, is restricted to the Loúros River drainage, Ionian Sea basin, Epirus Periphery. It is distinguished from Eudontomyzon hellenicus, the other nonparasitic Greek brook lamprey, occurring allopatrically in the Strymon River drainage, Aegean Sea basin, Central Macedonia Periphery, by possessing at the adult stage a relatively longer tail and a greater number of bicuspid teeth in both the first row of anterials and posterials, and at the ammocoete stage, by a relatively shorter trunk and longer tail and a less pigmented upper lip, tongue precursor bulb and lateral aspects of the elastic ridge. Taken individually, these three adult and five larval characters, varied in their diagnostic power from 71 to 88% for the adults and from 91 to 97% for the ammocoetes. However, in combination, these characters provide sufficient evidence to justify recognition of this new species, in addition to the wide distance (ca 400 km) separating it from its closest extant relative, as well as its independent origin.