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Shell habitus and COI mitochondrial gene sequences of one freshwater snail from Khios and three from Rhodes islands were analysed. Both methods confirmed assignment of these specimens to the genus Daphniola Radoman, 1973. Genetic distance between individuals from these two islands is surprisingly low, strongly suggesting that they belong to the same species, still undescribed. Comparison of COI sequences with other known species of this genus shows that the closest relative of the Khios and Rhodes populations is D. louisi Falniowski et Szarowska, 2000 from Attica. The results are discussed in the context of geological and climatic history of the Mediterranean.
A valvatiform hydrobiid gastropod, found in a spring at Dhiaselo, W of Sparta, N. Taigetos Mts., Peloponnese, Greece, was identified as Horatia hadei Gittenberger, 1982. Its protoconch sculpture, female reproductive organs and penis morphology are characteristic of Daphniola Radoman, 1973. Maximum likelihood phylogenetic analysis based on COI (cytochrome oxidase subunit I) fragments of mtDNA proved that the species is congeneric with D. exigua (A. Schmidt, 1856) and D. louisi Falniowski et Szarowska, 2000, and thus belongs to the genus Daphniola, and that D. hadei, D. exigua and D. louisi are species-level distinct taxa.
We studied the shell and penis morphology, and cytochrome oxidase subunit I (COI) gene sequences, in minute, valvatiform hydrobiid gastropods from Slovensky Kras, Slovakia. The morphology confirmed the assignment of the studied snails to the genus Hauffenia, while in the molecular tree they were placed within the Hydrobiidae, and not close to Hauffenia. The results indicate that the Slovak valvatiform hydrobiids are two taxa which presumably represent two genera: Hauffenia Pollonera, 1898 and Lobaumia Haase, 1993. More molecular data on the Austrian and Hungarian taxa are needed.
Twenty−six species of Rissoidae (Caenogastropoda: Littorinimorpha: Rissooidea) are described from the Badenian and Early Sarmatian of 14 localities in Austria and the Czech Republic (Molasse Basin, Styrian Basin, Vienna Basin) and from the Badenian of Coştei (Romania). For the first time, the early ontogenetic skeletal characters of these gastropods are described. Based on these features an indirect larval development with a planktotrophic veliger could be reconstructed for all investigated Mid−Miocene species. The status of Mohrensterniinae as a subfamily of the Rissoidae is confirmed by the morphology of the low conical protoconch, consisting of a fine spirally sculptured embryonic shell and a larval shell which is smooth except for growth lines. Transitions from embryonic shells to larval shells and from larval shells to teleoconchs are slightly thickened and indistinct. Whilst representatives of the subfamily Rissoinae characterise the marine Badenian assemblages, Mohrensterniinae predominate the Early Sarmatian faunas. We hypothesize that this take−over by the Mohrensterniinae was triggered by changes in the water chemistry towards polyhaline conditions. Consequently, the shift towards hypersaline conditions in the Late Sarmatian is mirrored by the abrupt decline of the subfamily. Four new species Rissoa costeiensis (Rissoinae) from the Badenian and Mohrensternia hollabrunnensis, Mohrensternia pfaffstaettensis, and Mohrensternia waldhofensis (Mohrensterniinae) from the Early Sarmatian are introduced.
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