Tsaagan is an extinct genus of dromaeosaurid theropod dinosaur that lived in Mongolia during the Late Cretaceous.
History[]
The holotype, MPC-D 100/1015 (prev. IGM 100/1015) was discovered in 1996 and classified as a specimen of Velociraptor. However, a CAT scan in May 1998 suggested need for a new genus, which was published in 2006. The name is intended to be read as one, translating to "white monster" in Mongolian (although it is a typo of the word "Tsagaan"). The holotype was found near Xanadu, Ömnögovi Province in the Campanian Djadochta Formation. It is a well-preserved skull and a vertebral series of 10 cervicals with a damaged left shoulder. It is the only specimen, an adult.
Description[]
It generally resembles Velociraptor but differs through the robusticity and smoothness on top, with autapomorphies including a long paroccipital processes, jugal that touches the squamosal and basipterygoids at the rear of the skull.
Classification[]
Norell et al. suggest that Tsaagan was a velociraptorine. A 2010 analysis suggests affinities closer to Linheraptor. Senter (2011) and Turner et al. (2012) suggest, however, that Linheraptor is synonymous with Tsaagan. Xu et al. (2015) reject this, finding differences between the two. Currie and Evans (2019) find:
| Eudromaeosauria |
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Paleoecology[]
Tsaagan is one of the only dromaeosaur remains (besides isolate teeth) from the Ukhaa Tolgod region, though it did share the Djdochta Formation with Velociraptor. Other animals from here include Protoceratops, Shuvuuia, Zalambdalestes, Kryptobaatar, troodontids and dromaeosaurids.