Horatia Bourguignat, 1887: is this genus really phylogenetically very close to Radomaniola Szarowska, 2006 (Caenogastropoda: Truncatelloidea)?

Horatia Bourguignat, 1887 was the first genus established for hydrobiid snails with valvatoid shell, and numerous valvatoid-shelled hydrobioids were classified as Horatia. The genus was the type one for some tribe/family-rank taxa. Thus it is one of the “crucial” hydrobiid genera. Horatia seems to inhabit only Croatia and Macedonia, and its type species: H. klecakiana Bourguignat, 1887, inhabits the springs in the Cetina River Valley. In the present paper the shell, operculum, soft part pigmentation, protoconch SEM microsculpture, female reproductive organs, and penis of H. klecakiana from the spring Studenci, N of Kučiće, in the valley of the Cetina River, Croatia, are described, to confirm the identity of the studied specimens with this species. Mitochondrial cytochrome oxidase subunit I (COI) and nuclear 18S ribosomal RNA gene sequences are used to infer phylogenetic relationships of Horatia, especially with Radomaniola and the sequence of Horatia from GenBank. The results suggest close relationships of the genus with Sadleriana, not with Radomaniola

Pseudamnicola exilis (Frauenfeld, 1863) in southern Greece: a remnant of a flock of species (Rissooidea: Hydrobiidae)?

The morphology of shell, penis, and female reproductive organs was studied in five populations of Pseudamnicola exilis (Frauenfeld) from southern Peloponnese and Kithira Island (Greece). No interpopulation differences were found in any of the characters. Thirty eight sequences of mitochondrial cytochrome oxidase subunit I (COI) and nuclear ribosomal 18S RNA genes were analysed. In COI 19 haplotypes, high haplotypy diversity, low nucleotide diversity in each population, and restricted gene flow between populations were found. NCA indicated allopatric fragmentation for all populations, and long-distance colonisation and/or past fragmentation for populations 4 and 5. Mismatch distribution in the most polymorphic population 4 reflected a bottleneck followed by population growth. The values of K2P interpopulation distances, though relatively low, pointed to congeneric distinct species within the Rissooidea. The monophyly of Pseudamnicola/Adrioinsulana clade was confirmed. Most probably the studied populations of Pseudamnicola were part of a flock of vicariant species little differentiated in morphology and ecology, many of which must have disappeared due to human impact