Otekaikea

Summary

Otekaikea is an extinct genus of toothed whale closely related to Waipatia. It is known from the late Oligocene (Chattian) of New Zealand.

Otekaikea
Temporal range: Late Oligocene. 24.2–23.6 Ma
Partial holotype skull of O. marplesi shown form above
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Infraorder: Cetacea
Parvorder: Odontoceti
Family: Waipatiidae
Genus: Otekaikea
Tanaka and Fordyce, 2014
Species
  • O. marplesi (Dickson, 1964) (type)
  • O. huata Tanaka and Fordyce, 2015

Description edit

 
Reconstructed skull of O. marplesi

Otekaikea is a medium-sized odontocete similar to Waipatia in the following characters: maxilla and occipital partly separated by parietal; flat dorsal surface of periotic; long posterior process of the periotic; and poorly developed ventromedial keel of the bulla. Differences from other archaic odontocetes include: broad dished face; elevated nodular subrhomboidal nasals and elevated frontals; smooth-surfaced premaxillary sac fossae without prominent premaxillary sulci developed posteriorly; premaxillae strongly bifurcated posteriorly, associated with bilateral posterior accessory foramina and elevated crests on the maxillae; periotic with long slender parallel-sided posterior process, and sharp apex of anterior process.[1]

Taxonomy edit

Otekaikea was originally described as a species of Prosqualodon, P. marplesi.[2] In 1994, it was referred to the genus Notocetus in the original description of Waipatia.[3] Preparation of the holotype, however, established its affinities with Waipatia, and Prosqualodon marplesi was given its own genus, Otekaikea, after the Otekaike Limestone in New Zealand where it was first discovered.[1]

A second species, Otekaikea huata, differs from the type species in having single-rooted posterior cheek teeth and a reduced ascending process of the premaxilla.[4]

References edit

  1. ^ a b Tanaka Y, Fordyce RE (2014) Fossil Dolphin Otekaikea marplesi (Latest Oligocene, New Zealand) Expands the Morphological and Taxonomic Diversity of Oligocene Cetaceans. PLoS ONE 9(9): e107972. doi:10.1371/journal.pone.0107972
  2. ^ Dickson MR (1964) The skull and other remains of Prosqualodon marplesi, a new species of fossil whale. N Z J Geol Geophys 7: 626–635. doi: 10.1080/00288306.1964.10422110
  3. ^ Fordyce RE (1994) Waipatia maerewhenua, new genus and new species (Waipatiidae, new family), an archaic Late Oligocene dolphin (Cetacea: Odontoceti: Platanistoidea) from New Zealand. Proc San Diego Soc Nat Hist 29: 147–176.
  4. ^ Tanaka, Yoshihiro and Fordyce, R. Ewan 2015. A new Oligo-Miocene dolphin from New Zealand: Otekaikea huata expands diversity of the early Platanistoidea. Palaeontologia Electronica 18.2.23A: 1-71 palaeo-electronica.org/content/2015/1161-fossil-platanistoid-dolphin