"Narynsuchus" is an extinct genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of thalattosuchia

Thalattosuchia

Thalattosuchia is the name given to a clade of marine crocodylomorphs from the Early Jurassic to the Early Cretaceous that had a cosmopolitan distribution. They are sometimes colloquially referred to as marine crocodiles or sea crocodiles, though they are not actually members of Crocodilia.The term...

n mesoeucrocodylia

Mesoeucrocodylia

Mesoeucrocodylia is the name of the clade that includes Eusuchia and the paraphyletic group Mesosuchia. The group appeared during the Early Jurassic, and continues to the present day....

n. Because it has not yet been formally described, it is currently considered a nomen nudum

Nomen nudum

The phrase nomen nudum is a Latin term, meaning "naked name", used in taxonomy...

. The name was first used in 1990 for fossil material found from a formation called the Balabansai Svita, which forms a lens

Lens (geology)

In geology a lens is a body of ore or rock or a deposit that is thick in the middle and thin at the edges, resembling a convex lens in cross-section. Adjective: "lenticular"....

 in site FTA-30 of the Sarykamyshsai 1 locality in the Fergana Valley

Fergana Valley

The Fergana Valley or Farghana Valley is a region in Central Asia spreading across eastern Uzbekistan, Kyrgyzstan and Tajikistan. Divided across three subdivisions of the former Soviet Union, the valley is ethnically diverse, and in the early 21st century was the scene of ethnic conflict...

 of Kyrgyzstan

Kyrgyzstan

Kyrgyzstan , officially the Kyrgyz Republic is one of the world's six independent Turkic states . Located in Central Asia, landlocked and mountainous, Kyrgyzstan is bordered by Kazakhstan to the north, Uzbekistan to the west, Tajikistan to the southwest and China to the east...

. The formation dates back to the Callovian

Callovian

In the geologic timescale, the Callovian is an age or stage in the Middle Jurassic, lasting between 164.7 ± 4.0 Ma and 161.2 ± 4.0 Ma. It is the last stage of the Middle Jurassic, following the Bathonian and preceding the Oxfordian....

 stage of the Middle Jurassic

Middle Jurassic

The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from 176-161 million years ago. In European lithostratigraphy, rocks of this Middle Jurassic age are called the Dogger....

. The type species

Type species

In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...

 of "Narynsuchus" is "N. ferganensis".

Material belonging to "Narynsuchus" consists of large and characteristically striated teeth as well as a robust left tibia

Tibia

The tibia , shinbone, or shankbone is the larger and stronger of the two bones in the leg below the knee in vertebrates , and connects the knee with the ankle bones....

. "Narynsuchus" is thought to have been larger than Sunosuchus

Sunosuchus

Sunosuchus is an extinct genus of goniopholidid mesoeucrocodylian. Fossils are known from China, Kyrgyzstan and Thailand and are Jurassic in age, although some may be Early Cretaceous. Five species are currently assigned to the genus: the type species S. miaoi and the species S. junggarensis, S....

, another crocodyliform from Sarykamyshsai 1, due to the greater size of the known elements belonging to the genus. This material was first recognized as belonging to a new crocodyliform in 1989, when it was referred to as an indeterminant species of Peipehsuchus

Peipehsuchus

Peipehsuchus is an extinct genus of teleosaurid crocodyliform from the Early Jurassic . The type species, P. teleorhinus, is known from China and fragmentary remains were found in the Callovian of Kyrgyzstan.-References:...

.