Gracilineustes

Gracilineustes is an extinct genus of marine crocodyliform that lived in the oceans during the Middle to Late Jurassic. Gracilineustes was a carnivore that spent much, if not all, its life out at sea.

Gracilineustes Temporal range: Callovian - Kimmeridgian, 167–155 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Holotype of G. leedsi, NHMUK PV R3540
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Suborder:	†Thalattosuchia
Family:	†Metriorhynchidae
Subfamily:	†Metriorhynchinae
Genus:	†Gracilineustes Young et al., 2010
Type species
†Gracilineuestes leedsi (Andrews, 1913)[1]
Other species
†G. acutus Lennier, 1887 [2]
Synonyms
Metriorhynchus laeve Andrews, 1913

Discovery and species

Skull and limb of G. leedsi

Fossil specimens referrable to Gracilineustes are known from Middle-Late Jurassic deposits of England and France.[3]

Valid species

• G. leedsi: Western Europe (England) of the Middle Jurassic (Callovian);[1] Metriorhynchus laeve is a junior synonym.
• G. acutus: Western Europe (France) of the Late Jurassic (Kimmeridgian) [2]

References

1. Andrews CW. 1913. A descriptive catalogue of the marine reptiles of the Oxford Clay, Part Two. London: British Museum (Natural History), 206 pp.
2. Lennier G. 1887. Description des fossiles du Cap de la Hève. Bulletin de la Société Géologique de Normandie, Le Havre 12: 17-98.
3. Young, Mark T., Brusatte, Stephen L., Ruta, M., Andrade, Marco B. 2009. "The evolution of Metriorhynchoidea (Mesoeucrocodylia, Thalattosuchia): an integrated approach using geometrics morphometrics, analysis of disparity and biomechanics". Zoological Journal of the Linnean Society 158: 801-859.