Musankwa

Musankwa
Temporal range: Triassic, Norian
Holotype femur (A) and tibia with astragalus (B)
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: †Sauropodomorpha
Clade: †Massopoda
Genus: †Musankwa
Species:
†M. sanyatiensis
Binomial name
†Musankwa sanyatiensis
Barrett et al., 2024

Musankwa is an extinct genus of massopodan sauropodomorph dinosaur from the Late Triassic (Norian) Pebbly Arkose Formation of Zimbabwe. The genus contains a single species, M. sanyatiensis, known from a partial leg. Musankwa represents the fourth dinosaur genus to be named from Zimbabwe.

Discovery and naming

Geographical, stratigraphic, and sedimentological details of the Musankwa discovery, including the holotype in situ (E)
Skeletal diagram of the holotype

The Musankwa holotype specimen, NHMZ 2521, was discovered in March 2018 by Paul Barrett in sediments of the Pebbly Arkose Formation of the Upper Karoo Group (Spurwing East Palaeosol site) on the shoreline of Spurwing Island in Lake Kariba, Zimbabwe. The specimen consists of an articulated partial right leg, including the femur, tibia, and astragalus, in addition to associated unidentifiable bone fragments. A fragment of the distal end of the fibula was also found in the field but lost during collection and preparation before its description.[1]

The Musankwa fossil material was mentioned in a 2020 review of the Upper Karoo Group's geology and paleontology, where it was preliminarily identified as belonging to a non-dinosaurian archosauromorph.[2] The material later was then alluded to in a 2023 conference abstract as belonging to a Riojasaurus-like sauropodomorph, before its formal description the following year.[3]

Life restoration of Musankwa sanyatiensis

In 2024, Barrett et al. described Musankwa sanyatiensis as a new genus and species of basal sauropodomorph based on these fossil remains. The generic name, Musankwa, honors the house boat of the same name that served as the paleontologists' laboratory and home while conducting the fieldwork during which the holotype was found. "Musankwa" is a Tonga word meaning "boy close to marriage". The specific name, sanyatiensis, references the Sanyati River which flows into Lake Kariba near the type locality.[1]

Musankwa is the fourth genus of dinosaurs to be named from Zimbabwe,[1] following "Syntarsus" rhodesiensis in 1969,[4] Vulcanodon in 1972,[5] and Mbiresaurus in 2022.[6]

Description

Based on more complete relatives, Musankwa was likely an obligate biped. As such, the body mass of the holotype individual was calculated at about 386 kilograms (851 lb).[1]

Classification

In their phylogenetic analyses, Barrett et al. (2024) recovered Musankwa as the basalmost member of the sauropodomorph clade Massopoda, with the Riojasauridae found to be the next diverging clade. Their results are displayed in the cladogram below:[1]

Massopoda

References

  1. ^ a b c d e Barrett, Paul M.; Chapelle, Kimberley E.J.; Sciscio, Lara; Broderick, Timothy J.; Zondo, Michel; Munyikwa, Darlington; Choiniere, Jonah N. "A new Late Triassic sauropodomorph dinosaur from the Mid-Zambezi Basin, Zimbabwe". Acta Palaeontologica Polonica. 69 (2): 227–241. doi:10.4202/app.01100.2023.
  2. ^ Sciscio, Lara; Viglietti, Pia A.; Barrett, Paul M.; Broderick, Timothy J.; Munyikwa, Darlington; Chapelle, Kimberley E. J.; Dollman, Kathleen N.; Edwards, Steve F.; Zondo, Michel; Choiniere, Jonah N. (2020-10-26). "Sedimentology and palaeontology of the Upper Karoo Group in the Mid-Zambezi Basin, Zimbabwe: new localities and their implications for interbasinal correlation". Geological Magazine. 158 (6): 1035–1058. Bibcode:2021GeoM..158.1035S. doi:10.1017/S0016756820001089. ISSN 0016-7568.
  3. ^ Barrett, Paul M.; Sciscio, Lara; Zondo, Michel; Broderick, Timothy J.; Munyikwa, Darlington; Viglietti, Pia A.; Edwards, Steve F.; Chapelle, Kimberley E. J.; Dollman, Kathleen N.; Choiniere, Jonah N. (2023). Faunal change across the Triassic–Jurassic boundary: New insights from the Mid-Zambezi Basin of Zimbabwe. 14th Symposium on Mesozoic Terrestrial Ecosystems and Biota. Vol. 306. pp. 30–32. doi:10.1002/ar.25219.
  4. ^ Raath, Michael A. (1969). "A new Coelurosaurian dinosaur from the Forest Sandstone of Rhodesia". Arnoldia. 4 (28): 1–25.
  5. ^ Raath, Michael A. (1972). "Fossil vertebrate studies in Rhodesia: a new dinosaur (Reptilia, Saurischia) from near the Triassic-Jurassic boundary". Arnoldia. 5: 1–2, 4.
  6. ^ Griffin, Christopher T.; Wynd, Brenen M.; Munyikwa, Darlington; Broderick, Tim J.; Zondo, Michel; Tolan, Stephen; Langer, Max C.; Nesbitt, Sterling J.; Taruvinga, Hazel R. (2022-08-31). "Africa's oldest dinosaurs reveal early suppression of dinosaur distribution". Nature. 609 (7926): 313–319. Bibcode:2022Natur.609..313G. doi:10.1038/s41586-022-05133-x. ISSN 0028-0836. PMID 36045297. S2CID 251977824.