Pronunciation: GWIE-bah-SOR-uh-day
Author: Jose Bonaparte
Year: 1999
Etymology: Guaiba lizard family
Locomotion: Bipedal
Synonyms: None known
Author: Jose Bonaparte
Year: 1999
Etymology: Guaiba lizard family
Locomotion: Bipedal
Synonyms: None known
[Martin D. Ezcurra, 2010]Definition
All archosaurs more closely related to Guaibasaurus candelariensis than to Carnotaurus sastrei or Saltasaurus loricatus.
About
Guaibasauridae is a group created by Jose Bonaparte in 1999 to house Guaibasaurus and its closest relatives which, at the time, were... none!
But thanks to spectacular foresight it now contains a grand total of six and two of them are a pairing in a new group called Saturnalinae. You know you've made it when your clade houses a clade!
Guaibasaurids are known from late Triassic formations in Brazil and Argentina but nailing them to a position on the dinosaur family tree that everyone agrees with has caused a few headaches. Once thought to be ancestral to the split between sauropodomorphs and theropods, Bonaparte found more characteristics in common with theropods which led to speculation that the elusive "ancestor of all dinosaurs" had more in common with theropods too. However, recent research shows that Guaibasaurids are the most primitive sauropodomorphs; small, bipedal and possibly omnivorous... though Guaibasaurus may turn out to be a theropod after all.
Click here to view Dinochecker's A-Z list of Guaibasaurids.
Etymology
Guaibasauridae is derived from "GuaÃba" (for the Rio GuaÃba Hydrographic Basin where the first specimen was discovered), and the Greek "sauros" (lizard) and "-idae" (family), named to house Guaibasaurus and its closest relatives.
References
• Bonaparte JF, Ferigolo J and Ribeiro AM (1999) "A new early Late Triassic saurischian dinosaur from Rio Grande do Sul State, Brazil". Proceedings of the Second Gondwana Dinosaur Symposium, edited by Tomida, Rich, and Vickers-Rich. National Science Museum Monographs, No. 15, Tokyo, 1999.
• Brett-Surman MK, Holtz TR jr, Farlow JO (2012) "The Complete Dinosaur: Second Edition (Life of the Past). Indiana University Press.
• Ezcurra MD (2010) "A new early dinosaur (Saurischia: Sauropodomorpha) from the Late Triassic of Argentina: a reassessment of dinosaur origin and phylogeny".
Journal of Systematic Palaeontology, Vol. 8, Issue 3, September 2010, pp 371–425.
