Sinosauropteryx
Three specimens have been assigned to "Sinosauropteryx prima": the holotype GMV 2123 (and its counter slab [opposite face], NIGP 127586), NIGP 127587, and D 2141. Another specimen, IVPP V14202, was assigned to the genus but not to the only species by Zhang and colleagues. The assignment of an additional larger specimen to "S. prima", GMV 2124, was later found to be in error. All of the fossils were found in the Jianshangou or Dawangzhangzi Beds of the Yixian Formation in the Beipiao and Lingyuan regions of Liaoning, China. These fossil beds have been dated to 124.6–122 million years ago, during the early Aptian stage of the Early Cretaceous.
Secernosaurus
Secernosaurus (meaning "severed lizard") is a genus of herbivorous dinosaur. "Secernosaurus" was a hadrosaur, a "duck-billed" dinosaur which lived during the Late Cretaceous. Its fossils have been found in Argentina.
Its name comes from the fact that it lived in South America, which during the Mesozoic Era was part of the southern supercontinent of Gondwana. Most other hadrosaurs lived in the northern supercontinent of Laurasia, so it was separated from its relatives. It was believed to be the only hadrosaur from Gondwana until the discovery of "Willinakaqe salitralensis " in 2011.
The type species is "Secernosaurus koerneri", described in 1979. A species named in 1984, "Kritosaurus australis", is thought to be synonymous.