A Miocene pygmy right whale fossil from Australia

Felix G Marx; Travis Park; Erich M G Fitzgerald; Alistair R Evans

doi:10.7717/peerj.5025

A Miocene pygmy right whale fossil from Australia

PeerJ. 2018 Jun 22:6:e5025. doi: 10.7717/peerj.5025. eCollection 2018.

Authors

Felix G Marx^{1

2

3}, Travis Park^{2

4}, Erich M G Fitzgerald^{3

4

5}, Alistair R Evans^{2

3}

Affiliations

¹ Directorate of Earth and History of Life, Royal Belgian Institute of Natural Sciences, Brussels, Belgium.
² School of Biological Sciences, Monash University, Clayton, Victoria, Australia.
³ Palaeontology, Museums Victoria, Melbourne, Victoria, Australia.
⁴ Department of Life Sciences, Natural History Museum, London, United Kingdom.
⁵ National Museum of Natural History, Smithsonian Institution, Washington, D.C., United States of America.

Abstract

Neobalaenines are an enigmatic group of baleen whales represented today by a single living species: the pygmy right whale, Caperea marginata, found only in the Southern Hemisphere. Molecular divergence estimates date the origin of pygmy right whales to 22-26 Ma, yet so far there are only three confirmed fossil occurrences. Here, we describe an isolated periotic from the latest Miocene of Victoria (Australia). The new fossil shows all the hallmarks of Caperea, making it the second-oldest described neobalaenine, and the oldest record of the genus. Overall, the new specimen resembles C. marginata in its external morphology and details of the cochlea, but is more archaic in it having a hypertrophied suprameatal area and a greater number of cochlear turns. The presence of Caperea in Australian waters during the Late Miocene matches the distribution of the living species, and supports a southern origin for pygmy right whales.

Keywords: Caperea; Cetotheriidae; Cochlea; Evolution; Fossil; Inner ear; Neobalaeninae; Victoria.

Grants and funding

This research was supported by a Marie Skłodowska-Curie Global Postdoctoral fellowship (656010/ MYSTICETI) to Felix G. Marx, and a Marie Skłodowska-Curie Individual Fellowship (748167/ECHO) to Travis Park. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.