Article · Wikipedia archive · Last revised Jun 9, 2026

Alienochelys

Alienochelys is an extinct genus of marine turtle known from Maastrichian-aged Cretaceous phosphates in Morocco. With a skull measuring 41.5 centimetres (1.36 ft) long, it would have been a very large turtle. It was first described as a member of the family Dermochelyidae, meaning that it is a relative of the modern leatherback turtle, though a 2018 study identifies it as a sister taxon of Ocepechelon belonging to the family Protostegidae, indicating that it may have been closer to the extinct Archelon. Unlike other sea turtles, Alienochelys' the jaws being adapted for a powerful crushing pattern well adapted for a durophagous lifestyle, as well as its unusual cranial characteristics.

Last revised
Jun 9, 2026
Read time
≈ 1 min
Length
261 w
Citations
6
Source
Alienochelys
Temporal range: Late Cretaceous,
Skull of specimen.
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Testudines
Suborder: Cryptodira
Family: Protostegidae
Genus: Alienochelys
de Lapparent de Broin, 2014
Type species
Alienochelys selloumi
de Lapparent de Broin, 2014
Life restoration of Alienochelys (middle right) and other animals of the Ouled Abdoun Basin source ↗

Alienochelys ("strange turtle") is an extinct genus of marine turtle known from Maastrichian-aged Cretaceous phosphates in Morocco.1 With a skull measuring 41.5 centimetres (1.36 ft) long, it would have been a very large turtle.2 It was first described as a member of the family Dermochelyidae, meaning that it is a relative of the modern leatherback turtle,2 though a 2018 study identifies it as a sister taxon of Ocepechelon belonging to the family Protostegidae, indicating that it may have been closer to the extinct Archelon.3 Unlike other sea turtles, Alienochelys' the jaws being adapted for a powerful crushing pattern well adapted for a durophagous lifestyle, as well as its unusual cranial characteristics.24

References

References

  1. "Fossilworks: Alienochelys". fossilworks.org. Retrieved 17 December 2021.
  2. de Lapparent de Broin, France; Bardet, Nathalie; Amaghzaz, Mbarek; Meslouh, Saïd (2014). "A strange new chelonioid turtle from the Latest Cretaceous Phosphates of Morocco". Comptes Rendus Palevol. 13 (2): 87–95. doi:10.1016/j.crpv.2013.07.008.
  3. Scavezzoni, I.; Fischer, V. (2018). "Rhinochelys amaberti Moret (1935), a Protostegid Turtle from the Early Cretaceous of France". PeerJ. 10 (6) e4594. doi:10.7717/peerj.4594. PMC 5898427. PMID 29666758.
  4. Cooper, S.L.A.; Marson, K.J.; Smith, R.E.; Martill, D. (2022). "Contrasting preservation in pycnodont fishes reveals first record of regurgitalites from the Upper Cretaceous (Maastrichtian) Moroccan phosphate deposits". Cretaceous Research. 131 (4). 105111. doi:10.1016/j.cretres.2021.105111.