Nichollsemys

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Nichollsemys
Temporal range: Late Cretaceous
84.9–70.6  Ma
Turtle skull fossil.jpg
Skull, Royal Tyrrell Museum in Alberta, Canada
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Testudines
Suborder: Cryptodira
Superfamily: Chelonioidea
Genus: Nichollsemys
Brinkman, 2006 [1]
Species
  • N. baieri(Brinkman, 2006)

Nichollsemys is a genus of extinct sea turtles. The only known species is Nichollsemys baieri. [2]

Contents

Taxonomy

Biostratigraphy and paleobiogeography of Late Cretaceous chelonioids of North America, with Nichollsemys (1) at upper left Biostratigraphy and paleobiogeography of Late Cretaceous chelonioids of North America.png
Biostratigraphy and paleobiogeography of Late Cretaceous chelonioids of North America, with Nichollsemys (1) at upper left

Fossils of the Nichollsemys have been found in Alberta, Canada, by Donald Brinkman. [3] The fossils found are all skulls.

The name of Nichollsemys is a tribute to Elizabeth Nicholls, a paleontologist from Canada who studied marine reptiles from the Triassic period. She had previously done work with Brinkman when they found the ichthyosaur genus Parvinatator. [4]

Evolution

  Panchelonioidea  

Toxochelys

 Protostegidae  

  Chelonioidea  

Corsochelys

Dermochelyidae

Nichollsemys

Allopleuron

Cheloniidae

Argillochelys

Procolpochelys

Eochelone

Puppigerus

Ctenochelys

Peritresius

Cabindachelys

Description

The full length of the Nichollsemys is unknown, but Brinkman made a chart of the length of some parts of the specimen. The length from the basioccipital to the premaxilla measures 11.4 cm, the width of all the quadrates measures 9.8 cm, the depth at level of the quadrates measures 7.1 cm, the intraorbital width measures 2 cm, and the length measures 3.6 cm. [5] The cranium has many things in common with that of Toxochelys: for example, they both have a rostrum basisphenoidale shaped like a rod.

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References