Muiscasaurus

These remains were found in 2010 in the middle of a limestone concretion, known as the Arcillolitas abigarradas Member, dating from the Barremian to Aptian epochs of the Lower Cretaceous.

[3] Like all advanced ichthyosaurs, Muiscasaurus must had a compact and streamlined body, with a tail shaped like a half moon and all four legs transformed into flippers.

[2] Muiscasaurus was described based on fossils that were classified as belonging to the Ophthalmosauridae family, which includes most of the ichthyosaurs that lived during the Jurassic and Cretaceous periods.

[2] Cladogram based in the phylogenetic analysis of Maxwell et al., 2015: Ophthalmosaurus Undorosaurus Acamptonectes Leninia Aegirosaurus Mollesaurus Muiscasaurus Brachypterygius Caypullisaurus Platypterygius Platypterygius australis Simbirskiasaurus Pervushovisaurus Sveltonectes Maiaspondylus Athabascasaurus Cryopterygius Janusaurus Arthropterygius Palvennia The following cladogram shows a possible phylogenetic position of Muiscasaurus in Ophthalmosauridae according to the analysis performed by Zverkov and Jacobs (2020).

[4] Acamptonectes densus Mollesaurus periallus Ophthalmosaurus natans Ophthalmosaurus icenicus Gengasaurus nicosiai Nannopterygius yasykovi Nannopterygius enthekiodon Nannopterygius saveljeviensis Nannopterygius borealis Arthropterygius volgensis Arthropterygius lundi Arthropterygius thalassonotus Arthropterygius hoybergeti Arthropterygius chrisorum Brachypterygius extremus Aegirosaurus leptospondylus Muiscasaurus catheti Leninia stellans Sveltonectes insolitus Athabascasaurus bitumineus Platypterygius americanus Acuetzpalin carranzai Platypterygius sachicarum Caypullisaurus bonapartei Grendelius mordax Grendelius alekseevi Grendelius pseudoscythicus Grendelius zhuravlevi Undorosaurus kielanae Undorosaurus nessovi Undorosaurus gorodischensis Platypterygius australis Plutoniosaurus bedengensis Simbirskiasaurus birjukovi Platypterygius hercynicus Sisteronia seeleyi Platypterygius platydactylus Maiaspondylus lindoei In addition to Muiscasaurus, in the Paja Formation has been recovered other kind of ichthyosaur, Kyhytysuka sachicarum; it is distinguished of Muiscasaurus for their teeth and cranial features, including thicker, robust teeth with grooved tooth enamel.