Published online by Cambridge University Press: 02 April 2018
Four new species of the methane seep-inhabiting kalenterid bivalve genus Caspiconcha Kelly in Kelly et al., 2000 are described: Caspiconcha basquensis from the late Albian of northern Spain, C. yubariensis from the late Albian of northern Japan, C. raukumaraensis from the late Albian to mid-Cenomanian of New Zealand, and C. lastsamurai from the Campanian of northern Japan. The earliest confirmed record of the genus is known from the latest Jurassic. It reached its maximum diversity in the Albian and declined in diversity and abundance through the Late Cretaceous. The youngest species, C. lastsamurai, is currently known from a single specimen only.