365-Million-Year-Old Lungfish Unearthed in South Africa

Tuesday, December 24, 2019

Illustration of Isityumzi mlomomde (lower right) and other Late Devonian freshwater ecosystem creatures including the early tetrapod Unzantsia. Image credit: Maggie Newman.

A new genus and species of lungfish that lived approximately 365 million years ago (Famennian stage of the Late Devonian period) has been identified from fossils found in South Africa.

Lungfish (subclass Dipnoi) are a group of lobe-finned fish with their origins stretching back to the Early Devonian period, over 410 million years ago.

They reached a peak of diversity and abundance throughout the Devonian with close to 100 species described from that time period.

More than 25 species originated in the eastern Gondwanan (Australia) waters and others are known to have lived in temperate tropical and subtropical waters of China and Morocco.

The newly-discovered species represents the only record of Late Devonian lungfish remains from the western Gondwana (South America and Africa).

Named Isityumzi mlomomde, the ancient creature is also the only lungfish known from the Witpoort Formation of South Africa.

Isityumzi mlomomde was found about 10,000 km from a previous species described in Morocco, and is of interest because it existed in a high latitude (70 degrees south) or polar environment at the time,” said Dr. Alice Clement, a paleontologist at Flinders University and corresponding author of a paper published in the journal PeerJ.

Isityumzi mlomomde’s tooth plates, scales and two parasphenoids (a bone in the cranium of many vertebrates) were found between 1999 and 2017 by Dr. Robert Gess, a paleontologist with Rhodes University, Albany Museum, and Wits University and co-author of the paper.

“This lungfish material is significant for a number of reasons,” Dr. Clement explained.

“Firstly, it represents the only Late Devonian lungfish known from the western Gondwana. During this period, about 372-359 million years ago, South Africa was situated next to the South Pole.”

“Secondly, Isityumzi mlomomde seems to have lived in a thriving ecosystem, indicating this region was not as cold as the polar regions of today.”

“The animal would still have been subject to long periods of winter darkness, very different to the freshwater habitats that lungfish live in today when there are only six known species of lungfish living only in Africa, South America and Australia.”


R.W. Gess & A.M. Clement. 2019. A high latitude Devonian lungfish, from the Famennian of South Africa. PeerJ 7: e8073; doi: 10.7717/peerj.8073

Source: www.sci-news.com/