Short Note Bollettino della Società Paleontologica Italiana, 55 (1), 2016, 79-80. Modena ISSN 0375-7633 doi:10.4435/BSPI.2016.07 Contina, a new name for the genus Vacekia Conti & Szabó, 1989 (Mollusca: Gastropoda), preoccupied by Vacekia Buckman, 1904 (Mollusca: Ammonoidea) Andrea Di cencio Studio Tecnico Geologia e Paleontologia, via Mattoncetti, 6, San Casciano Val di Pesa, I-50026 Firenze, Italy; andreadicencio@geologiaepaleontologia.eu A case of homonymy between the genera Vacekia Buckman, 1904 and Vacekia Conti & Szabó, 1989 has been highlighted. Vacekia Buckman, 1904 (p. 156) is an ammonite ranging from the upper Toarcian (Aalensis Zone) to the middle Aalenian (Murchisonae Zone) (Elmi & Caloo Fortier, 1985; Caloo Fortier, 1985; Linares & Sandoval, 1992; Sandoval et al., 2012). Vacekia Conti & Szabó, 1989 (p. 33) is a gastropod based on a type species erected by Vacek (1886), that is known from the middle Jurassic sediments of Cape St. Virgilio Oolite (Conti & Szabó, 1989). In this contribution I revise the nomenclature of Vacekia Conti & Szabó, 1989 following the Principle of Priority (art. 23) of the International Code of Zoological Nomenclature (International Commission of Zoological Nomenclature, 1999). M.A. Conti and J. Szabó were informed about the discovery of this case of homonymy. SYSTEMATIC PALEONTOLOGY Class GaStRoPoDa Cuvier, 1797 Order aRcHaeoGaStRoPoDa Thiele, 1925 Superfamily tRocHacea Rainesque, 1815 Family tRocHiDae Rainesque, 1815 Subfamily ?MonoDontinae Cossmann, 1916 Remark to the subfamily attribution - Conti & Szabó (1989), during their reinvestigation of fossils of Cape St. Virgilio Oolite studied by Vacek (1886), considered Vacekia Conti & Szabó, 1989 as a genus incertae sedis because its type species exhibits similarities and differences with genera belonging to both the subfamilies MonoDontinae Cossman, 1916 and cHiLoDontinae Wenz, 1938. However, in the writer’s opinion there are stronger resemblances between Vacekia Conti & Szabó, 1989 and Praelittorina Kutassy, 1937, whith respect to the similarities with other genera, and this could suggest the attribution of Vacekia Conti & Szabó, 1989 to MonoDontinae. This option is here preferred, even if the ornamentation of the peristome is not well known. Vacek igured three views of the holotype, (pl. 18, ig. 10; Fig. 1a-c), but according to Conti & Szabó (1989) the ornamentation of the peristome provided by Vacek is an artifact due to preparation. Unfortunately Conti & Szabó did not support their conclusion with a new igure. Genus Contina nom. nov. 1989 Vacekia conti & Szabó, p.33. Type species - Littorina gardana (Vacek, 1886, p. 109; pl. XVIII, ig. 10). Derivatio nominis - The genus is dedicated to Maria Alessandra Conti, one of two authors who reinvestigated the gastropod fauna of the Cape St Virgilio Oolite studied by Vacek (1886). S. P. I. S O C I E T A ' P A L E O N T O L O G I C A I T A L I A N A Fig. 1 - Contina gardana (Vacek, 1886), holotype GBA 1886/005/0066 ; a-c: from Vacek (1886); d: from Conti & Szabó (1989). Scale bar: 1 cm.