Gualicho is an extinct genus of theropod dinosaur that lived in Argentina during the Late Cretaceous[1][2][3].
History[]
Gualicho is known from the Late Cenomanian-Early Turonian-aged Huincul Formation. MPCN PV 0001 is the holotype, a partial skeleton lacking crania with 4 dorsals, 3 mid-caudals, gastralia, the left shoulder girdle, the left forelimb, lower right arm, the end of the pubes, the right thighbone and a fragment of the lower left, the upper ends of the shin and calf bones, both metatarsi and 3 toes of the right foot. Most of these were still articulated but most were eroded.[4][5]
Gualicho was once suggested to be synonymous with Aoniraptor, from the same formation, based on vertebral similarities. If true, Gualicho would take priority and MPCA-Pv 804/1 to 804/25 (the last sacral vertebra, six proximal caudal vertebrae, four mid-caudal vertebrae and five haemal arches) would be referred as the second specimen.[6][7] A 2022 study suggests that it and Deltadromeus are basal ornithomosaurs that form a clade[8].
Description[]
Skeletal reconstruction of Gualicho. White colored parts are the recovered remains.
Gualicho has reduced forelimbs with three fingers; it was once suggested only two were present, but a 2020 study suggests otherwise. If Gualicho were an allosauroid, this would indicate carnosaurs had similar limb reduction to tyrannosaurs and abelisaurs. Gualicho has an enigmatic classification, either being a megaraptoran or a neovenatorid. It was suggested either neovenatorids and megaraptorans were carnosaurs or that megaraptorans neovenatorids were closer related to coelurosaurs rather than carnosaurs.[9][10]
References[]