<I>Bohaskaia monodontoides</I>, a new monodontid (Cetacea, Odontoceti, Delphinoidea) from the Pliocene of the western North Atlantic Ocean

Abstract

ABSTRACT Here we describe Bohaskaia monodontoides, a new taxon of beluga-like odontocete cetacean from the early Pliocene Yorktown Formation of Virginia and North Carolina. Among odontocetes, Bohaskaia shares key characteristics of the rostrum and face with belugas (Delphinapterus leucas), narwhals (Monodon monoceros), and Denebola brachycephala from the late Miocene of Baja California, thus placing it as a member of the Monodontidae. It also displays autapomorphies that merit its placement in a new genus and species. Both Denebola and Bohaskaia occurred in warmer latitudes than those of extant monodontids, even accounting for extralimital records. Such data from the fossil record of Monodontidae indicates that putative cold climate adaptations of living monodontids might have appeared under different environmental conditions and that their Holarctic and sub-Arctic distribution is a relatively recent phenomenon. ABSTRACT Here we describe Bohaskaia monodontoides, a new taxon of beluga-like odontocete cetacean from the early Pliocene Yorktown Formation of Virginia and North Carolina. Among odontocetes, Bohaskaia shares key characteristics of the rostrum and face with belugas (Delphinapterus leucas), narwhals (Monodon monoceros), and Denebola brachycephala from the late Miocene of Baja California, thus placing it as a member of the Monodontidae. It also displays autapomorphies that merit its placement in a new genus and species. Both Denebola and Bohaskaia occurred in warmer latitudes than those of extant monodontids, even accounting for extralimital records. Such data from the fossil record of Monodontidae indicates that putative cold climate adaptations of living monodontids might have appeared under different environmental conditions and that their Holarctic and sub-Arctic distribution is a relatively recent phenomenon.