A new genus and species, Slovenitriacanthus saksidai, from southwestern Slovenia, of the Upper Cretaceous basal tetraodontiform fish family Cretatriacanthidae (Plectocretacicoidea)

A 15.9 mm SL specimen from the Lipica Formation of Upper Santonian-Lower Campanian age (about 82−84 MYA) at Sepulje, near Tomaj, about 14 km southeast of Komen, in southwestern Slovenia, is described as Slovenitriacanthus saksidai, new genus and species. It is the second known taxon of the Upper Cretaceous basal tetraodontiform fish family Cretatriacanthidae, which was previously represented only by the holotype of Cretatriacanthus guidottii Tyler and Sorbini 1996 from the Upper Campanian-Lower Maastrichtian of Nardo (Puglia), southeastern Italy (about 70 MYA). The diminutive size of Slovenitriacanthus saksidai and its well-ossified and presumably adult body are similar to those of all of the other known specimens of the three Upper Cretaceous families that comprise the superfamily Plectocretacicoidea, supporting the proposal that a reduced size of 25 mm SL or less is a synapomorphy of the superfamily.