Thyasiridae Dall, 1901

Kiel, Steffen, Sami, Marco & Taviani, Marco, 2023, Mollusks (Gastropoda, Bivalvia) from Miocene cold-seep deposits in northern Italy: revisions and additions, European Journal of Taxonomy 910, pp. 115-160 : 140

Family Thyasiridae Dall, 1901

Remarks

Thyasirids are generally small and rare in the Calcari a Lucina deposits. The only previous records are three specimens assigned to Channelaxinus sp. from the Ca’ Cavalmagra site ( Kiel & Taviani 2017). This is a remarkable contrast to coeval seep deposits in both the Pacific and the Caribbean regions ( Amano et al. 2015, 2022; Kiel & Hansen 2015; Hryniewicz 2022; Kiel et al. 2022), where large thyasirids typically assigned to Conchocele Gabb, 1866 often dominate the assemblages. In the Cenozoic seep deposits of the Mediterranean region, only a few larger thyasirids reaching 30 mm were reported from the Eocene Buje site in Croatia ( Natalicchio et al. 2015), large thyasirids are absent from the Pliocene Stirone river seep deposit ( Kiel & Taviani 2018), and thyasirids tend to be small and uncommon at present-day Mediterranean seeps ( Olu et al. 2004; Taviani 2014).