Trinisaura

Trinisaura Temporal range: Late Cretaceous, 80–66 Ma PreЄ Є O S D C P T J K Pg N
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Clade:	Dinosauria
Order:	†Ornithischia
Suborder:	†Ornithopoda
Clade:	†Elasmaria
Genus:	†Trinisaura Coria et al., 2013
Type species
†Trinisaura santamartaensis Coria et al., 2013

Trinisaura is an extinct genus of ornithopod dinosaur known from the lower levels of the Late Cretaceous Snow Hill Island Formation (lower Campanian stage) of James Ross Island, Antarctica. It contains a single species, Trinisaura santamartaensis.^[1]

The species was in 2013 named by Rodolfo Aníbal Coria e.a. The generic name honours the geologist Trinidad Diaz. The specific name refers to the Santa Marta Cove site where the specimen was in 2008 found by Coria and Juan José Moly.^[1] That same year, the find was reported in the scientific literature.^[2]

The holotype, MLP-III-1-1, consists of a partial skeleton lacking the skull, of a subadult individual about 1.5 metres (4.9 ft) in length.^[1]

Phylogeny

The cladogram below follows Coria et al., 2013 phylogenetic analysis. Trinisaura is found to be an ornithopod, however the inclusion of Thescelosaurus neglectus is necessary to determine whether it is a basal iguanodont.^[1]

Ornithopoda	Hypsilophodon foxii Gasparinisaura cincosaltensis Trinisaura santamartaensis Talenkauen santacrucensis Anabisetia saldiviai Tenontosaurus Dryomorpha Dryosauridae Ankylopollexia

In 2015, it along with several other Patagonian and Antarctic ornithopods was found to be a part of the basal group of iguanodonts, Elasmaria.

Cladogram based in the phylogenetic analysis of Rozadilla et al., 2015:

	Hypsilophodon Thescelosaurus Iguanodontia Elasmaria Gasparinisaura Morrosaurus Trinisaura Macrogryphosaurus Notohypsilophodon Talenkauen Anabisetia Parksosaurus Kangnasaurus Rhabdodontidae Tenontosaurus Dryomorpha

References

1. Coria, R. A.; Moly, J. J.; Reguero, M.; Santillana, S.; Marenssi, S. (2013). "A new ornithopod (Dinosauria; Ornithischia) from Antarctica". Cretaceous Research. doi:10.1016/j.cretres.2012.12.004.
2. Coria, R.A., Moly, J.J., Reguero, M., Santillana, S., 2008, "Nuevos restos de Ornithopoda (Dinosauria, Ornithischia) de la Fm. Santa Marta, Isla J. Ross, Antártida", Ameghiniana 45(4), Supl., 25R