| Tietasaura Temporal range:Early Cretaceous,Valanginian–Hauterivian | |
|---|---|
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| Skeletal reconstruction (known material in white) | |
Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Dinosauria |
| Clade: | †Ornithischia |
| Clade: | †Ornithopoda |
| Clade: | †Elasmaria |
| Genus: | †Tietasaura Bandeira et al., 2024 |
| Species: | †T. derbyiana |
| Binomial name | |
| †Tietasaura derbyiana Bandeira et al.,2024 | |
Tietasaura (meaning "Tieta lizard") is anextinct genus ofelasmarianornithopod dinosaur from theEarly CretaceousMarfim Formation of Brazil. The genus contains asingle species,T. derbyiana, known from a single incompletefemur.Tietasaura is notable for being the firstornithischian dinosaur ever named from Brazil.
TheTietasauraholotype specimen, NHM-PV R.3424, was discovered in 1906 during a series of expeditions byLondon's Natural History Museum to South America, lasting from 1859 to 1906. Some of the fossils found during these trips were described in publications in 1860 and 1907.[1][2] This particular fieldwork was conducted along a beach near the Bahia-São FranciscoRailway in the city ofSalvador inBahia, Brazil. This locality belongs to the Marfim Formation of theRecôncavo Basin. The specimen, which consists of thedistal end of leftfemur, is among the first dinosaur remains found in South America. While it is now confidently regarded as belonging to a dinosaur, early observations labeled the bone as belonging to "Hyposaurussp." (adyrosauridcrocodyliform) in the collections of the Natural History Museum,[3] and the museum's digital collections inaccurately list it as a specimen ofSarcosuchus hartti (apholidosaurid crocodyliform).[4]
In 2024, Bandeira et al.describedTietasaura derbyiana as a new genus and species of elasmarian ornithopod based on these fossil remains. Thegeneric name,Tietasaura, combines "Tieta"—the name of the main character in the Brazilian novelTieta do Agreste—and "saura" (σαύρα), the feminine declination of theGreek word "sauros", meaning "lizard". The name "Tieta" is also a nickname for "Antonieta" inPortuguese, which means "priceless"; the describing authors use this meaning to reflect the specimen's value as the first ornithischian named from Brazil. Thespecific name,derbyiana, honors geologistOrville A. Derby and his contributions to paleontology in Brazil.[3]
In theirphylogenetic analyses, Bandeira et al. (2024) recoveredTietasaura as an ornithopod member of theElasmaria, as thesister taxon toNotohypsilophodon. Their results are displayed in thecladogram below:[3]
