Tusked walruses (Carnivora: Odobenidae) from the Miocene–Pliocene Purisima Formation of Santa Cruz, California (U.S.A.): a new species of the toothless walrus Valenictus and the oldest records of Odobeninae and Odobenini ...

• Main Authors: Boessenecker, Robert W., Poust, Ashley W., Boessenecker, Sarah J., Churchill, Morgan
• Format: Dataset
• Language: unknown
• Published: Taylor & Francis 2024
• Subjects: Evolutionary Biology; FOS Biological sciences; Environmental Sciences not elsewhere classified; Ecology; Biological Sciences not elsewhere classified; Inorganic Chemistry; FOS Chemical sciences; Arctic; walrus*
• Online Access: https://dx.doi.org/10.6084/m9.figshare.25102294.v1; https://tandf.figshare.com/articles/dataset/Tusked_walruses_Carnivora_Odobenidae_from_the_Miocene_Pliocene_Purisima_Formation_of_Santa_Cruz_California_U_S_A_a_new_species_of_the_toothless_walrus_i_Valenictus_i_and_the_oldest_records_of_Odobeninae_and_Odobenini/25102294/1

Currently limited to cold climates near the Arctic circle, living walruses are the sole survivors of a previously much more diverse clade that occupied coastal waters throughout the northern hemisphere during the Mio–Pliocene. Though pinniped faunas have the highest diversity of walruses in the Miocene, the Purisima Formation of California records a moderately diverse assemblage of four walrus species. We report new specimens of tusked walruses (Odobeninae) including the oldest known members of Odobeninae, and Odobenini, and fossils of the specialized toothless odobenine walrus Valenictus Mitchell, 1961. Among these is the new species Valenictus sheperdi sp. nov., represented by a complete skull and referred post-crania from lower Pliocene strata within the Purisima Formation (5.33–4.89 Ma). Additionally, we report a geochronologically younger skull of Valenictus chulavistensis Deméré, 1994 from further up section (4.89–3.59 Ma). Expanded phylogenetic analysis recovers Odobeninae including Ontocetus Leidy, ...