Language: English with bilingual summary in English and Italian
The collection of holoplanktonic Mollusca (Gastropoda, Heteropoda and Euthecosomata) housed in the "Dipartimento di Scienze della Terra" at Torino, including type and illustrated material published by Bellardi (1873), Audenino (1897), Sacco (1904) and Pavia & Robba (1979), is systematically revised. A total of 46 taxa (3 Heteropoda and 43 Euthecosomata), predominantly originating from Miocene and Pliocene deposits in Northern Italy (with main emphasis on the Miocene of the Turin Hills) are recognised, 9 of which remain in open nomenclature.
A new family, Sphaerocinidae, three new genera (Diacrolinia, Edithinella and Ireneia) and a new species, Cuvierina jagti, are introduced in the Euthecosomata. Neotypes are designated for 4 species (Ireneia calandrellii, I. testudinaria, Clio multicostata and Gamopleura taurinensis), whereas lectotypes are selected for 15 other euthecosomatous species. New illustrations are provided for all taxa. A list of samples present in the collection and a list specifying species per locality concludes the paper.
In Appendix 1 two new species from the Messinian of Tetti Borelli (Moncucco Torinese), viz. Clio giulioi and ?Diacrolinia elioi, are described, and in Appendix 2 Ireneia marqueti sp. nov. and I. nieulandei sp. nov. are erected.