Rarosaurus

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Rarosaurus
Temporal range: late Maastrichtian, 67–66 Ma
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Rarosaurus singularis.jpg
Reconstruction of several individuals of Rarosaurus singularis
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Superorder: Sauropterygia
Order: Plesiosauria
Family: Polycotylidae
Genus: Rarosaurus
Kaddumi, 2009 [1]
Species:
R. singularis
Binomial name
Rarosaurus singularis
Kaddumi, 2009

Rarosaurus is an extinct genus of polycotylid plesiosaur that lived during the Late Cretaceous. It contains one valid species, R. singularis and it was found in the Muwaqqar Chalk Marl Formation of Jordan. [1]

Contents

Discovery and naming

The holotype, a partial rostrum with teeth, was discovered in the Muwaqqar Chalk Marl Formation of Jordan. It was named and described by Kaddumi (2009). [1]

Description

Rarosaurus is known from the rostral portion of a fossil skull, which is well preserved and bears teeth. The fossil is about twenty centimetres long and very elongate. The surface of the bone is rugose, marked by small holes and grooves. The teeth are relatively short and conical; the first tooth in the jaw protrudes far forward. [1]

It is notable for being the latest-surviving polycotylid and is currently the only one from the late Maastrichtian. [1]

Naming

The generic name Rarosaurus means "rare lizard", and is attributed to the paucity of plesiosaur fossils where it was found. The specific name singularis refers to the type specimen of Rarosaurus being the only plesiosaur specimen found from the area. [1]

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References

  1. 1 2 3 4 5 6 Kaddumi, H.F. (2009). "On the remains of the first plesiosaur (Reptilia: Sauropterygia) from Harrana with a description of a new genus and species of Polycotylidae". Fossils of the Harrana Fauna and the Adjacent Areas. Eternal River Museum of Natural History. pp. 158–162.