Genus
Valid Extinct

Toretocnemus

Merriam 1903

Toretocnemus is an extinct genus of ichthyosaurs that lived during the Carnian stage of the Upper Triassic in what is now North America. Two species are known, T. californicus and T. zitelli, first described in 1903 by John Campbell Merriam from fossils discovered in the Hosselkus Limestone, Shasta County. The second species was first seen by Merriam as belonging to a distinct genus, but in 1999 it was reclassified into the original taxon. Toretocnemus fossils are primarily known from California, although some specimens are also reported from Alaska and Mexico. With Qianichthyosaurus, the taxon is part of the Toretocnemidae, of which it is also the type genus.

Temporal range
Triassic
Jurassic
Cretaceous
Paleogene
Neogene
252 201 145 66 0 Ma
PBDB occurrences
4
Group
Ichtyosaures
Carnivore nektonic Marine
Toretocnemus
click to enlarge
Various fossils pertaining to the holotype of the Triassic ichthyosaur Toretocnemus californicus. This image is derived from plate 24 in Merriam (1903), done by an uncredited artist. The arrangement of the individual figures has been modified from the original. Original description: Toretocnemus californicus n. gen. and sp. Figures reproduced natural size from the type specimen. Fig. 1. — Inferior side of right posterior limb. t, tibia. Fig. 2. — Right anterior limb. r, radius. Fig. 3.— Pelvic arch. Fig. 4. — Middle dorsal vertebrae and a rib from the same region. © Uncredited · Public domain · Wikimedia
Toretocnemus
Toretocnemus
PBDB Wikipedia
Classification
Ichthyosauria Unranked clade
Hueneosauria Unranked clade
Longipinnati Suborder
Toretocnemidae Family
Toretocnemus Genus
Fossil sites 4 geolocated sites
Distribution
Top countries
🇺🇸 United States
2
🇲🇽 Mexico
2
Geological formations
Hosselkus
2
Antimonio
2
Temporal distribution
Norian (227.3–205.7 Ma)
1
Carnian (237–227.3 Ma)
3
Species (3)
Merriamia zitteli subjective synonym of Toretocnemus zitteli 252 Ma
Toretocnemus californicus 237 Ma
Toretocnemus zitteli 252 Ma
Synonyms (3)
Leptocheirus replaced by Toretocnemus
Merriamia subjective synonym of Toretocnemus
Rhachitrema subjective synonym of Toretocnemus
Images 7
Bibliography
Original description
J. C. Merriam. 1903. New Ichthyosauria from the Upper Triassic of California. University of California Publications, Bulletin of the Department of Geology 3(12):249-263
Bibliography (3)
V.-H. Reynoso. 2006. Research on fossil amphibians and reptiles in Mexico, from 1869 to early 2004 (including marine forms but excluding pterosaurs, dinosaurs, and obviously, birds). Studies on Mexican Paleontology 24:209-231
S. G. Lucas and C. M. González-León. 1995. Ichthyosaurs from the Upper Triassic of Sonora and the biochronology of Triassic ichthyosaurs. Geological Society of America Special Paper 301:17-20 DOI ↗
J. C. Merriam. 1903. New Ichthyosauria from the Upper Triassic of California. University of California Publications, Bulletin of the Department of Geology 3(12):249-263