Molecular taxonomy and phylogeny of Italian Lepidurus taxa (Branchiopoda: Notostraca)

Notostraca taxonomy is controversial, mainly owing to the high intraspecific variability of morphological characters; other complexity factors are represented by the consistent rate of reproductive variation. We undertook the molecular analyses of Italian Lepidurus taxa through the characterization of 12S, 16S and COI mitochondrial genes in new L. apus demes and in the L. couesii populations recently discovered in Southern Italy. For L. apus, the analysis of a wider data set (both in terms of molecular markers and of analysed populations) confirms the previously suggested specific rank of differentiation between its so far recognized subspecies, the Italian L. apus lubbocki and the European L. apus apus. The Italian L. couesii samples pertain to a well-defined taxonomic entity, strictly related to Canadian L. couesii. In 12S dendrograms, this taxon strongly diverges from the other North American Lepidurus species, but the relationships among nearctic taxa are unresolved. On the other hand, a high affinity between Italian/Canadian L. couesii and the circumpolar species L. arcticus is scored and a possible descent from a common ancestor is hypothesized. © 2009 Unione Zoologica Italiana.