Genus Pratulum Iredale, 1924

Type species. Cardium thetidis Hedley, 1902

Remarks. This genus has never been reported from modern New Zealand seeps or from fossil seep deposits globally. Traditionally, it has been regarded as a subgenus of Nemocardium Meek, 1876 . However, Poorten (2013) recently reviewed Nemocardium and argued that Pratulum Iredale, 1924, should be elevated to genus level. This opinion is followed here.