New Fossilized Vertebrate a First for Mozambique

Newly discovered fossils in Mozambique reveal a previously unknown ancient animal that researchers have named Niassodon mfumukasi, or The Queen of Lake Niassa.

The name comes from the local Chiyao language and pays homage to the matriarchal society of the Yao people as well as Lake Niassa, also known as Lake Malawi, the third largest lake in Africa.

The fossil specimen is a type of dicynodont, mammal-like reptiles that were dominant in the Late Permian era on into the Triassic period. It is estimated that the new species lived about 250 million years ago.

The researchers who discovered the fossil in 2009 note that the fossil record held by Mozambique remains largely unexplored. Niassodon mfumukasi represents the first new genus (and species) of a fossil vertebrate from Mozambique. The fossil takes the place as a holotype - the sample which all subsequent species samples will be compared against.

Dicynodonts are well-studied, but specific parts of their anatomy, such as cranial anatomy and inner ear morphology remain obscure. Because the new fossil was incomplete, the researchers had to learn as much as they could from only a little material, just the animal's head and a few lower vertebrae. 

Researchers used the newfound specimen to reconstruct the lesser-known aspects of the genus' biology by making color-coded 3-D models of each individual bone in the fossil. The results are comprehensive and provide with great detail and clarity the cranial anatomy of the new species, the researchers said. Scientists can use this information gleaned by the analysis of the new species to better understand the anatomy of other dicynodont species on the record.

"By using micro-computed tomography it was possible to reconstruct digitally not only the bones of Niassodon but also to build a virtual model of its brain," the Field Museum reported in a statement. "This reveals new information on the brain anatomy of early synapsids, which is important for understanding the evolution of many features of the mammalian brain. The reconstruction of the brain and inner ear anatomy developed for Niassodon is the most detailed presented to date for an early synapsid. Using the digital data acquired in the tomographies, it was possible to isolate all individual bones preserved which allowed the researchers to create a new topological color code, codified mathematically, for the cranial bones. This code will allow the researchers to standardize the colors used in similar digital model built for other animals."

The fossil is on display at the Lourinhã Museum in Portugal, but soon will be returned to Mozambique, where it will become part of the collections of the National Museum of Geology in Maputo.

A full report on the fossil and its analysis can be read in the open-access journal PLOS One.