''Tutusius'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

tetrapod from the

Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, wh ...

of South Africa, containing a single species, ''Tutusius umlambo''. It was described from the +/- 360 myo Gondwana locality of

Waterloo Farm lagerstätte The Waterloo Farm lagerstätte is a Famennian lagerstätte in South Africa that constitutes the only known record of a near-polar Devonian coastal ecosystem. History and discovery The Waterloo Farm Lagerstätte is an approximately 360 millio ...

on the south-eastern coast of

South Africa South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring coun ...

, which at the time was located within the

Antarctic Circle The Antarctic Circle is the most southerly of the five major circles of latitude that mark maps of Earth. The region south of this circle is known as the Antarctic, and the zone immediately to the north is called the Southern Temperate Zone. So ...

. Together with the find of '' Umzantsia amazana'' from the same locality, this provides the first evidence that Devonian tetrapods were not restricted to the

tropics The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also refer ...

as was formerly believed, and suggests that they may have been global in distribution. Waterloo Farm

fossils A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

have been metamorphosed and intensely flattened, with the bone tissue replaced by secondary metamorphic mica that is partially altered to kaolinite and chlorite during uplift. They also provide the first evidence of Devonian tetrapods from the continent of

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

, and only the second and third such taxa from Gondwana.

Taxonomy

''Tutusius umlambo'' is known from a single

cleithrum The cleithrum (plural cleithra) is a membrane bone which first appears as part of the skeleton in primitive bony fish, where it runs vertically along the scapula. Its name is derived from Greek κλειθρον = "key (lock)", by analogy with "cla ...

(a bone of the

shoulder girdle The shoulder girdle or pectoral girdle is the set of bones in the appendicular skeleton which connects to the arm on each side. In humans it consists of the clavicle and scapula; in those species with three bones in the shoulder, it consists ...

) discovered at the

, South Africa. It was described in 2018 by palaeontologists Robert Gess and Per Erik Ahlberg in 2018. The generic name is in honour of Archbishop

Desmond Tutu Desmond Mpilo Tutu (7 October 193126 December 2021) was a South African Anglican bishop and theologian, known for his work as an anti-apartheid and human rights activist. He was Bishop of Johannesburg from 1985 to 1986 and then Archbish ...

, in recognition of his contribution to the political and social development of South Africa. The specific name is from

isiXhosa Xhosa (, ) also isiXhosa as an endonym, is a Nguni language and one of the official languages of South Africa and Zimbabwe. Xhosa is spoken as a first language by approximately 8.2 million people and by another 11 million as a secon ...

“umlambo”, meaning “river”, referring to the depositional environment. The lagerstätte dates to the

Late Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, wher ...

roughly 360 million years ago. ''Tutusius'', along with ''

Umzantsia ''Umzantsia'' is an extinct genus of limbed stegocephalians ('tetrapods', in the broad sense) from the Devonian of South Africa. It contains a single species, ''Umzantsia amazana''. The genus is based on ~360 million year old skull and shoulder ...

'' from the same lagerstätte, are the first evidence of Devonian

tetrapod Tetrapods (; ) are four-limbed vertebrate animals constituting the superclass Tetrapoda (). It includes extant and extinct amphibians, sauropsids ( reptiles, including dinosaurs and therefore birds) and synapsids ( pelycosaurs, extinct t ...

s beyond 30° in latitude from the

equator The equator is a circle of latitude, about in circumference, that divides Earth into the Northern and Southern hemispheres. It is an imaginary line located at 0 degrees latitude, halfway between the North and South poles. The term can also ...

and on the

supercontinent In geology, a supercontinent is the assembly of most or all of Earth's continental blocks or cratons to form a single large landmass. However, some geologists use a different definition, "a grouping of formerly dispersed continents", which leav ...

Gondwana Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final sta ...

(except for a single body fossil and footprint from what is now Australia). The lagerstätte would have been in the south polar region, and the two genera demonstrate early tetrapods were not restricted to the warm

. They also make it possible that the transition from

fish Fish are Aquatic animal, aquatic, craniate, gill-bearing animals that lack Limb (anatomy), limbs with Digit (anatomy), digits. Included in this definition are the living hagfish, lampreys, and Chondrichthyes, cartilaginous and bony fish as we ...

to tetrapod occurred at the poles instead of the tropics.

Description

''Tutusius'' is represented by a single bone from the shoulder girdle, the cleithrum. It tapers to a point anteroventrally and carries a single attachment scar for the scapulocoracoid, which extends along the anteroventral process, forms a v-shaped dorsal peak, and ends posteriorly in a projecting buttress. The cleithrum lacks ornament and has a distinct flexure point demarcating the obliquely sloping ventral half of the bone from the more vertical dorsal half. The blade of the cleithrum is broad and thin. It differs from all other tetrapod cleithra in the presence of a projecting posterior flange, with striated texture and a jagged margin, on the middle part of the blade.

References

{{Taxonbar, from=Q96411419 Prehistoric tetrapods