Vespersaurus
Holotype foot bones
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Dinosauria
Clade: Saurischia
Clade: Theropoda
Family: †Noasauridae
Subfamily: †Noasaurinae
Genus: †Vespersaurus
Langer et al., 2019
Type species
Vespersaurus paranaensis
Langer et al., 2019

Vespersaurus (meaning "western lizard") is a genus of noasaurid theropod dinosaur from the Cretaceous Rio Paraná Formation in the Paraná Basin, Brazil. The type and only species is V. paranaensis, which would have lived in the giant prehistoric Botucatu Desert.[5]

Etymology

Life restoration

The generic name is derived from the Latin "vesper," meaning "evening/west," in reference to the town Cruzeiro do Oeste ("Western Cross") near which the fossils were found, and the Greek "sauros," meaning "lizard." The specific name refers to the Paraná state.[5]

Discovery and naming

Size comparison

After the discovery of numerous skeletons of the pterosaurs Caiuajara and Keresdrakon at the Cemitério dos Pterossauros site near Cruzeiro do Oeste, the remains of small theropods were uncovered between 2011 and 2015. One of these was named and described in 2019 as Vespersaurus. The holotype, MPCO.V 0065d, was recovered from the Late Cretaceous period, found on dark red sandstones in the Rio Paraná Formation in the Paraná Basin, Brazil. Footprints belonging to Vespersaurus or a similar one-toed theropod were discovered near Cruzeiro do Oeste as early as the 1970s.[5]

Description

Frontal bone and tooth

The taxon is notable for its distinct, functionally monodactyl foot anatomy, where the singularly large third digit would have borne most of the weight while walking. Based on the proportions of its holotype remains (MPCO.V 0065d), Vespersaurus was a small theropod with an estimated body length of 1–1.5 metres (3.3–4.9 ft). This makes it comparable in size to Noasaurus and Masiakasaurus. The estimated body mass of Vespersaurus is 11.28 kilograms (24.9 lb), nearly that of the ornithischians Jeholosaurus shangyuanensis and Gasparinisaura cincosaltensis.[5]

Ichnology

Footprints pertaining to a functionally monodactyl dinosaur found near Cianorte were attributed to Vespersaurus or to a close relative.[5] Those footprints were found in association with the ichnospecies Brasilichnium elusivum.[6][7] It had been suggested that Vespersaurus footprints and/or Brasilichnium elusivum could have originated myths regarding footsteps of a saint near Cianorte.[8][9] In 2023, Leonardi et al. described these footprints as belonging to a new ichnogenus and ichnospecies, which they named Farlowichnus rapidus.[10]

Palaeobiology

In 2023, Barbosa and colleagues tested Vespersaurus' tooth and two pedal unguals using a Finite Element Analysis. They found that the teeth were not well suited to handle struggling prey items, nor well-equipped to handle hard food items, having an ideal bite angle of 45 degrees. The stresses on the unguals, in contrast, were nearly identical throughout the three different scenarios they tested, indicating that the feet were not specialised for any particular task. Based on this, the team concluded that Vespersaurus did not fill a top predator niche in the Brazilian Caiua desert where it lived, but instead filled a more generalist niche, focussing on small prey items or having an opportunistic feeding strategy.[11]

See also

References

  1. ^ Canejo L, Holgado B, Weinschütz LC, Ricetti JH, Wilner E, Kellner AW (2022). "Novel information on the cranial anatomy of the tapejarine pterosaur Caiuajara dobruskii". PLOS ONE. 17 (12). e0277780. Bibcode:2022PLoSO..1777780C. doi:10.1371/journal.pone.0277780. PMC 9754175. PMID 36520711.
  2. ^ de Souza GA, Soares MB, Weinschütz LC, Wilner E, Lopes RT, de Araújo OM, Kellner AW (2021). "The first edentulous ceratosaur from South America". Scientific Reports. 11 (1): Article number 22281. Bibcode:2021NatSR..1122281D. doi:10.1038/s41598-021-01312-4. PMC 8602317. PMID 34795306.
  3. ^ Barbosa, G. G.; Langer, M. C.; de Oliveira Martins, N.; Montefeltro, F. C. (2023). "Assessing the palaeobiology of Vespersaurus paranaensis (Theropoda, Noasauridae), Cretaceous, Bauru Basin – Brazil, using Finite Element Analysis". Cretaceous Research. 150. 105594. Bibcode:2023CrRes.15005594B. doi:10.1016/j.cretres.2023.105594. S2CID 258952922.
  4. ^ Kellner, Alexander W. A.; Weinschütz, Luiz C.; Holgado, Borja; Bantim, Renan A. M.; Sayão, Juliana M. (August 19, 2019). "A new toothless pterosaur (Pterodactyloidea) from Southern Brazil with insights into the paleoecology of a Cretaceous desert". Anais da Academia Brasileira de Ciências. 91 (suppl 2): e20190768. doi:10.1590/0001-3765201920190768. ISSN 0001-3765. PMID 31432888.
  5. ^ a b c d e Langer, Max Cardoso; de Oliveira Martins, Neurides; Manzig, Paulo César; de Souza Ferreira, Gabriel; de Almeida Marsola, Júlio César; Fortes, Edison; Lima, Rosana; Sant’ana, Lucas Cesar Frediani; da Silva Vidal, Luciano; da Silva Lorençato, Rosangela Honório; Ezcurra, Martín Daniel Ezcurra (2019). "A new desert-dwelling dinosaur (Theropoda, Noasaurinae) from the Cretaceous of south Brazil". Scientific Reports. 9 (1): 9379. Bibcode:2019NatSR...9.9379L. doi:10.1038/s41598-019-45306-9. PMC 6594977. PMID 31243312.
  6. ^ Leonardi, G. (1977). "Two new ichnofaunas (vertebrates and invertebrates) in the eolian Cretaceous sandstones of Caiuá Formation in northwest Paraná". In Atlas do I Simpósio Geral Regional. Sociedade Brasileira de Geologia, São Paulo: 112–128.
  7. ^ Leonardi, G. (1994) Annotated Atlas of South America tetrapod footprints (Devonian to Holocene) with an appendix on Mexico and Central America. CPRM, Brasília
  8. ^ Caetano, João Marcus Vale; Ponciano, Luiza Corral Martins de Oliveira (2021) Cultural Geology, Cultural Biology, Cultural Taxonomy, and the Intangible Geoheritage as New Strategies for Geoconservation. Geoheritage 13:79. doi:10.1007/s12371-021-00603-6
  9. ^ Mayor A., Sarjeant W.A.S. (2001) The folklore of footprints in stone: from classical antiquity to the present. Ichnos 8:143–163. doi:10.1080/10420940109380182
  10. ^ Leonardi, Giuseppe; Fernandes, Marcelo Adorna; Carvalho, Ismar de Souza; Schutzer, Julia Beatrice; Silva, Rafael Costa da (2023-09-30). "Farlowichnus rapidus new ichnogen., new ichnosp.: A speedy and small theropod in the Early Cretaceous Botucatu paleodesert (Paraná Basin), Brazil". Cretaceous Research: 105720. doi:10.1016/j.cretres.2023.105720. ISSN 0195-6671.
  11. ^ Barbosa, Gabriel Gonzalez; Langer, Max Cardoso; de Oliveira Martins, Neurides; Montefeltro, Felipe Chinaglia (2023-05-26). "Assessing the palaeobiology of Vespersaurus paranaensis (Theropoda, Noasauridae), Cretaceous, Bauru Basin – Brazil, using Finite Element Analysis". Cretaceous Research. 150: 105594. Bibcode:2023CrRes.15005594B. doi:10.1016/j.cretres.2023.105594. ISSN 0195-6671. S2CID 258952922.
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