Description of a new toothed mysticete from the Late Oligocene of San Juan de La Costa, B.C.S., México

This paper describes a toothed mysticete that belongs to a basal family found in Oligocene sedimentary rocks deposited in the North Pacific Ocean. The material that is described here belongs in the Chattian stage of the Oligocene, and it was collected near Arroyo El Saladito from the San Juan Member...

Full description

Saved in:
Bibliographic Details
Published in:Journal of South American earth sciences 2019-01, Vol.89, p.337-346
Main Authors: Solis-Añorve, Azucena, González-Barba, Gerardo, Hernández-Rivera, René
Format: Article
Language:English
Subjects:
Cetacea
Evolution
Mysticeti
Oligocene
Teeth
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This paper describes a toothed mysticete that belongs to a basal family found in Oligocene sedimentary rocks deposited in the North Pacific Ocean. The material that is described here belongs in the Chattian stage of the Oligocene, and it was collected near Arroyo El Saladito from the San Juan Member in the El Cien Formation, Baja California Sur, México. The sedimentary environment of this area has been interpreted to be a continental platform with nutrient-rich waters combined with anoxic conditions. Therefore, the specimens that have been found in the phosphorite layers lived in an environment of shallow coastal waters. The material described is a dentary fragment, a skull and fragments of the teeth. The new taxon is located within the Superfamily Aetiocetoidea due to the presence of functional teeth, which have a slightly globose shape with eight slightly triangular apices. Niparajacetus palmadentis presents a morphology that contrasts with other toothed whales. For example, it shows an elongated and wide skull in the posterior region with a triangular shape, and its estimated total length is 3.2–3.5 m. •New specimen that belongs to the Aetiocetoidea Superfamily, characterized by presenting teeth in their adult form, is described.•This is one of the first descriptions of toothed whales for México.•It is presented as a new genus and species, with anatomical characteristics that distinguish it within other taxa within the Superfamily.•The material was collected in the upper Humboldt layer, interpreted as material deposited by storm events.•It is one of the largest toothed mysticete skulls from the late Oligocene.
ISSN:0895-9811
1873-0647
DOI:10.1016/j.jsames.2018.11.015