Pampadromaeus

Pampadromaeus Temporal range: Late Triassic, 225Ma PreЄ Є O S D C P T J K Pg N ↓
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Clade:	Dinosauria
Clade:	Eusaurischia
Suborder:	†Sauropodomorpha
Genus:	†Pampadromaeus Cabreira et al., 2011
Species:	† P. barberenai
Binomial name
Pampadromaeus barberenai Cabreira et al., 2011

Pampadromaeus is an extinct genus of basal sauropodomorph dinosaurs known from the Triassic of Rio Grande do Sul, southern Brazil.^[1]

Discovery

Pampadromaeus is known only from the holotype specimen ULBRA-PVT016, a disarticulated, partial but well preserved skeleton from a single individual which includes most of the skull bones and the lower jaws; dorsal, sacral and caudal vertebrae; elements of the shoulder girdle and the forelimbs, an ilium and elements of the hindlimbs. It was collected in the upper Hyperodapedon biozone from the Alemoa Member of the Santa Maria Formation (Rosário do Sul Group) in the "Janner" (also known as "Várzea do Agudo") locality, geopark of Paleorrota, dating to the Carnian faunal stage of the early Late Triassic, about 230-228 million years ago.^[1]

Description

Pampadromaeus was a small bipedal animal. It shows a mosaic of basal and derived traits. It differs from other sauropodomorphs by a combination of characters. Some of these are shared with some members of the sister group of the Sauropodomorpha, the Theropoda: the premaxilla is pointed downwards forming a subnarial gap with the maxilla and the anterior-most teeth are unserrated; in the location where with theropods the fenestra promaxillaris is positioned, a small depression is present. Basal traits consist of a large skull, a short thighbone, the possession of just two sacral vertebrae and the presence of fifteen teeth in the pterygoid.^[1]

There were four teeth in the premaxilla and about twenty in both the maxilla and the lower jaw for a total of eighty-eight. The teeth were large, elongated, lanceolate, slightly recurved, sharply pointed and coarsely serrated. The lower leg was much longer than the thighbone, indicating Pampadromaeus was a good runner.^[1]

Etymology

Pampadromaeus was first named by Sergio F. Cabreira, Cesar L. Schultz, Jonathas S. Bittencourt, Marina B. Soares, Daniel C. Fortier, Lúcio R. Silva and Max C. Langer in 2011 and the type species is Pampadromaeus barberenai. The generic name is derived from Quechua pampa, "plain", in reference to the present landscape of the site, and Greek δρομεύς, dromeus, "runner", referring to the cursorial habits; the Latinised spelling variant dromaeus is used. The specific name honours the Brazilian paleontologist Mário Costa Barberena.^[1]

Phylogeny

Pampadromaeus was found to be a basal sauropodomorph in four different cladistic analyses. The describers emphasized however, that this position was not strongly supported, showing the difficulties of determining the affinities of such early forms with the basal Dinosauromorpha, Saurischia, Sauropodomorpha and Theropoda.^[1]

References

v t e Fauna and Flora of Paleorrota Geopark Rio Grande do Sul Fauna Aetosaurs Stagonolepis Archosaurs Barberenachampsa nodosa Barberenasuchus brasiliensis Cerritosaurus Chanaresuchus Decuriasuchus Fitossauros Karamuru vorax Prestosuchus chiniquensis Procerosuchus Proterochampsa nodosa Protorosaurus Rauisuchus tiradentes Rhadinosuchus gracilis Spondylosoma Teyumbaita sulcognathus Teyuwasu Cynodonts Belesodon magnificus Brasilitherium Brasilodon Candelariodon Chiniquodon Charruodon Tetracuspidatus Exaeretodon riograndensis Gomphodontosuchus Brasiliensis Irajatherium hernadezi Luangwa Massetognathus Menadon Minicynodon Protheriodon estudianti Protuberum cabralensis Prozostrodon brasiliensis Riograndia Santacruzodon hopsoni Therioherpeton cargnini Traversodon Stahleckeri Dicynodonts Dinodontosaurus pedroanum Dinodontosaurus turpior Jachaleria candelariensis Stahleckeria Trucidocynodon Dinosaurs Staurikosaurus Guaibasaurus Pampadromaeus Sacisaurus Saturnalia tupiniquim Unaysaurus Mesosaurus Mesosaurus Pareiasaurus Provelosaurus brasiliensis Procolophons Candelaria barbouri Procolophon brasiliensis Procolophon pricei Procolophon trigoniceps Rhynchosaurs Hyperodapedon huenei Hyperodapedon mariensis Hyperodapedon sanjuanensis Temnospondylis Bageherpeton longignathus Sangaia lavinai Stereospondyli Insects Sanctipaulus mendesi Others Clevosaurus brasiliensis Dinocephalians Pampaphoneus biccai Soturnia caliodon Tiarajudens eccentricus Paleorrota's Flag. Dinotchê: The mascot Paleorrota. Flora Lycophytas Brasilodendron pedroanum Cyclodendron sp. Pteridospermatophytas Dicroidium odontopteroides Dicroidium zuberi Pteridophytas Asterotheca sp. Botrychiopsis plantianum Botrychiopsis valida Neomariopteris sp. Osmundites brasiliensis Pecopteris sp. Stephanophyllites sp. Sphenophytas Phyllotheca brevifolia Phyllotheca longifolia Sphenopteris sp. Neocalamites sp. Glossopteris Gangamopteris obovata Gangamopteris sulriograndensis Glossopteris angustifolia Glossopteris. brasiliensis Glossopteris browniana Glossopteris communisi Glossopteris indica Glossopteris occidentalis Cordaites Cordaites hislopii Kawizophyllum sp. Ginkgophytas Baieroxylon cicatricum Cheirophyllum speculare Chiropteris sp. Ginkgoites antarctica Sphenobaiera sp. Conifers Brachyphyllum sp. Buriadia sp. Cordaicarpus brasilianus Cordaicarpus cerronegrensisi Cordaicarpus fanatinensis Cordaicarpus truncata Coricladus quiteriensis Kaokoxylon zalesskyi Pagiophyllum sp. Samaropsis gigas Samaropsis kurtzii Samaropsis millaniana Samaropsis rigbyi Samaropsis seixasi Sommerxylon spiralosus Bennettitales Nilssonia sp. Williamsonia sp.