Planicoxa is a genus of advanced iguanodontian dinosaur from the Early Cretaceous of North America. It is known from the partial skeletons of several individual specimens. Its fossils were discovered in Utah, United States.
The type species for the genus is Planicoxa venenica, first described by Tony DiCroce and Kenneth Carpenter in 2001. Its discovery was made in the Poison Strip Sandstone Member of the Cedar Mountain Formation in Grand County, Utah, United States. Planicoxa refers to the flat appearance of the ilium formed by horizontal folding over of the postacetabular process (rear portion of the ilium), the defining characteristic of the genus; venenica, the species name, is Latin for “poison” in reference to the Poison Strip Sandstone Member of the Cedar Mountain Formation where the discovery was made. This new taxon is represented by a well-preserved ilium, femora, tibiae, and vertebrae, as well as other material. The femora are classical ornithopod, but the ilium has a short, horizontal postacetabular process that is functionally an antitrochanter. The discovery of P. venenica adds significant new information to the Barremian-Albian fauna of the Cedar Mountain Formation.
A second species, P. depressa, was created by Carpenter and Wilson (2008) for material previously named Camptosaurus depressus by Charles Gilmore in 1909. That material was collected from the Lakota Formation near the town of Hot Springs, South Dakota. It too has the odd flat ilium formed by the horizontal postacetabular process. This species differs from P. venenica in that the ilium is not as arched, has a thicker (more robust) preacetabular process (long, forward projection of the ilium), a shallower acetabular notch (hip-socket), and a proportionally narrower brevis shelf (a shelf for muscles on the inside of the rear part of the ilium). It is known from some vertebrae and two ilia. Isolated iguanodontid bones from the Lakota Formation probably belong to this species. In 2011, it was assigned to its own genus, Osmakasaurus.
DiCroce & Carpenter, 2001
DiCroce & Carpenter, 2001
Aquilarhinus (meaning "eagle snout" after the unusual beak morphology) is a genus of hadrosaurid ornithopod dinosaur from the Aguja Formation from Texas in the United States. The type and only species is Aquilarhinus palimentus. Due to its unusual dentary, it has been inferred to have had shovel-like beak morphology, different from the beaks of other hadrosaurs. It was originally classified as a Kritosaurus sp. before being reclassified as a new genus in 2019.Aralosaurini
Aralosaurini is a tribe of basal lambeosaurine hadrosaurs endemic to Eurasia. It currently contains Aralosaurus (from the Aral sea of Kazakhstan) and Canardia (from Toulouse, Southern France).Camptosaurus
Camptosaurus ( KAMP-toh-SAWR-əs) is a genus of plant-eating, beaked ornithischian dinosaurs of the Late Jurassic period of western North America and Europe. The name means 'flexible lizard' (Greek καμπτος/kamptos meaning 'bent' and σαυρος/sauros meaning 'lizard').Canardia
Canardia is an extinct genus of aralosaurin lambeosaurine dinosaur known from the Late Cretaceous Marnes d’Auzas Formation (late Maastrichtian stage) of Toulouse, Haute-Garonne Department, southern France. The type species Canardia garonnensis was first described and named by Albert Prieto-Márquez, Fabio M. Dalla Vecchia, Rodrigo Gaete and Àngel Galobart in 2013.Choyrodon
Choyrodon is a genus of hadrosauroid dinosaur from the Early Cretaceous Albian-age Khuren Dukh Formation of Mongolia. The type and only species is Choyrodon barsboldi. The generic name is derived from the city of Choyr, and -odon, from Greek for tooth; the specific name barsboldi honours paleontologist Rinchen Barsbold. The material consists of a holotype partial skull and cervical ribs, with two other partial skulls both with associated postcranial material. It was found to be the sister taxon of Eolambia.Elasmaria
Elasmaria is a clade of iguanodont ornithopods known from Cretaceous deposits in South America, Antarctica, and Australia.Galleonosaurus
Galleonosaurus (meaning "galleon lizard" as the upper jaw bone resembles an upturned galleon) is a genus of basal ornithopod dinosaur from the Wonthaggi Formation of the Gippsland region of Victoria, Australia. The type and only species is G. dorisae, described by Herne et al. in 2019.Iguanacolossus
Iguanacolossus (meaning Iguana Colossus from the genus name Iguana and the Latin word Colossus) is a genus of herbivorous iguanodontian dinosaur. It is a basal iguanodontian which lived during the Early Cretaceous period in what is now Utah, United States; known from UMNH VP 20205, the associated holotype with a partial skeleton of a single individual.Iguanodontia
Iguanodontia (the iguanodonts) is a clade of herbivorous dinosaurs that lived from the Middle Jurassic to Late Cretaceous. Some members include Camptosaurus, Dryosaurus, Iguanodon, Tenontosaurus, and the hadrosaurids or "duck-billed dinosaurs". Iguanodontians were one of the first groups of dinosaurs to be found. They are among the best known of the dinosaurs, and were among the most diverse and widespread herbivorous dinosaur groups of the Cretaceous period.Jaxartosaurus
Jaxartosaurus is a genus of hadrosaurid dinosaur similar to Corythosaurus which lived during the Late Cretaceous. Its fossils were found in Kazakhstan.Jeyawati
Jeyawati is a genus of hadrosauroid dinosaur which lived during the Turonian stage of the Late Cretaceous. The type species, J. rugoculus, was described in 2010, based on fossils recovered in the U.S. state of New Mexico.The holotype, MSM P4166, was discovered in the Moreno Hill Formation. A cladistic analysis indicates that Jeyawati was more plesiomorphic (ancestral) than Shuangmiaosaurus, Telmatosaurus, and Bactrosaurus, but more derived (less like the common ancestor) than Eolambia, Probactrosaurus, and Protohadros.Koshisaurus
Koshisaurus is a monospecific genus of basal hadrosauroid from the Kitadani Formation in Japan. The discovery of the genus suggests that hadrosauroids had higher diversity along the eastern margin of Asia in the Early Cretaceous. "Koshi" means an old Japanese regional name including Fukui prefecture where fossils of the genus were discovered.Laiyangosaurus
Laiyangosaurus ("Laiyang lizard") is a genus of saurolophine hadrosaurid from the Late Cretaceous of China. It is known from one species, L.youngi, found in the Laiyang Basin within the province of Shandong.Lapampasaurus
Lapampasaurus is an extinct genus of hadrosaurid known from the Late Cretaceous Allen Formation (late Campanian or early Maastrichtian stage) of La Pampa Province, Argentina. It contains a single species, Lapampasaurus cholinoi.The generic name refers to the Argentine province of La Pampa. The specific name honours the late collector José Cholino. The material includes cervical, dorsal, sacral and caudal vertebrae, the forelimb girdle, and the partial hindlimb.Osmakasaurus
Osmakasaurus is a genus of herbivorous iguanodontian dinosaur. It is a basal iguanodontian which lived during the lower Cretaceous period (Valanginian age) in what is now Buffalo Gap of South Dakota, United States. It is known from the Chilson Member of the Lakota Formation. This genus was named by Andrew T. McDonald in 2011 and the type species is Osmakasaurus depressus. O. depressus was previously referred to as Camptosaurus depressus, and was first described in 1909 by Charles W. Gilmore.Plesiohadros
Plesiohadros is an extinct genus of hadrosauroid dinosaur. It is known from a partial skeleton including the skull collected at Alag Teg locality, from the Campanian Djadochta Formation of southern Mongolia. The type species is Plesiohadros djadokhtaensis.Proplanicoxa
Proplanicoxa is a genus of iguanodont dinosaur which existed in what is now England during the Early Cretaceous period (late Barremian stage, around 126 mya).The holotype and only specimen of Proplanicoxa, BMNH R 8649, is composed of thirteen dorsals, a sacrum with ilia, parts of the pubis and ischium. The fossils were found in 1916 by Reginald Walter Hooley on the Isle of Wight from the upper Wessex Formation of England. BMNH R 8649 was originally assigned to Vectisaurus valdensis Hulke 1879 (=Mantellisaurus atherfieldensis) by Galton in 1976. The specimen was assigned to its own genus and species by Kenneth Carpenter and Yusuke Ishida in 2010, and the type species is Proplanicoxa galtoni. The generic name is derived from “before” (pro in Greek) and Planicoxa in reference to the postacetabular process of the ilium trending towards the horizontal as seen even stronger in Planicoxa, and the specific name honors Peter Galton. It may be synonymous with Mantellisaurus.Sahaliyania
Sahaliyania (from "black" in Manchu, a reference to the Amur/Heilongjiang River) is a genus of lambeosaurine hadrosaurid dinosaur (crested duckbilled dinosaur) from the Late Cretaceous of Heilongjiang, China.Xuwulong
Xuwulong is a genus of hadrosauroid dinosaur from the Early Cretaceous period. It lived during the early Cretaceous period (Aptian-Albian age) in what is now Yujingzi Basin in the Jiuquan area, Gansu Province of northwestern China. It is known from the holotype – GSGM F00001, an articulated specimen including a complete cranium, almost complete axial skeleton, and complete left pelvic girdle from Xinminpu Group. Xuwulong was named by You Hailu, Li Daqing and Liu Weichang in 2011 and the type species is Xuwulong yueluni.