The new fossil lungfish genus, Isityumzi mlomomde, was found about 10,000km 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, Flinders University said in a statement made available to Business Insider SSA on Wednesday, December 18th, 2019.
Isityumzi mlomomde means “a long-mouthed device for crushing” in the isiXhosa language (one of the official languages of South Africa).
Flinders University researcher Dr. Alice Clement says the “scrappy” fossil remains including tooth plates and scales were found in the Famennian Witpoort Formation off the western cape of South Africa.
“This lungfish material is significant for a number of reasons,” Dr. Clement says.
“Firstly it represents the only Late Devonian lungfish known from Western Gondwana (when South America and Africa were one continent). During this period, about 372-359 million years ago, South Africa was situated next to the South Pole,” she says.
“Secondly, the new taxa from the Waterloo Farm Formation seems to have lived in a thriving ecosystem, indicating this region was not as cold as the polar regions of today.”
What are Lungfish?
Lungfish are a group of fish most closely related to all tetrapods – all terrestrial vertebrates including amphibians, reptiles, birds, and mammals.
Dr. Clement says the animal would still have been subject to long periods of winter darkness, very different from 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.
Around 100 kinds of primitive lungfish (Dipnoi) evolved from the early Devonian period more than 410 million years ago. More than 25 originated in Australian (Gondwanan) and others are known to have lived in temperate tropical and subtropical waters of China and Morocco in the Northern Hemisphere.
“In this way, a lungfish is more closely related to humans than it is to a goldfish!” says Dr. Clement, who has been involved in naming three other new ancient lungfish.
Dr. Clement's paper titled, ‘A high latitude Devonian lungfish, from the Famennian of South Africe’ (2019) was published in PeerJ (Journal of Life and Environmental Sciences) and was supported by a Vice-Chancellor’s Award for Early Career Research in 2017.