Ischnochitonidae Dall, 1889

Family Ischnochitonidae Dall, 1889 View in CoL

Genus Ischnochiton Gray, 1847

Type species. Chiton textilis Gray, 1828 , by subsequent designation ( Gray 1847b: 168). For synonymy, see Kaas & Van Belle 1990.

Distribution. Ischnochiton is known from the Jurassic to the Recent, with a widespread extant circumglobal distribution, except for the northern Atlantic and Arctic Oceans ( Kaas & Van Belle 1990). The fossil record extends back to the Jurassic of Germany ( Fiedel & Keupp 1988), the Eocene in Europe ( U.K. and Ukraine: Bielokrys 1999; Cherns & Schwabe 2019), the upper Eocene or lower Oligocene in Washington, U.S.A. ( Dell’Angelo et al. 2011 a), the Oligocene of France ( Dell’Angelo et al. 2020b) and New Zealand ( Lee et al. 2014; Wu & Lee 2024), the Miocene of Africa ( Tanzania: Davis 1954), Indonesia ( Sumatra: Van der Vlerk 1931), the Miocene-Pleistocene of Europe (Dell’Angelo et al. 2004, 2015a; Garilli et al. 2005; Studencka & Dulai 2010), Australia and New Zealand ( Cotton 1964; Beu & Maxwell 1990), Pliocene-Pleistocene of U.S.A. ( Berry 1940; Campbell 1993), the Pleistocene of Japan ( Itoigawa et al. 1976), Uruguay ( Rojas & Urteaga 2011) and Red Sea ( Dell’Angelo et al. 2020a), the Holocene of Japan ( Kuroda et al. 1980).

Remarks. The genus Ischnochiton shows a high number of species treated in this work, 17 in all, reported by source area (Mediterranean, NE Atlantic and Paratethys), while for a better identification and differentiation, the examined species are reported, in the tables that summarize the main diagnostic characters, in two groups which highlight the different tegmentum sculpture: