Narthecoceratidae 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 actively mobile carnivorous cephalapod, essentially a Nautiloid

Nautiloid

Nautiloids are a large and diverse group of marine cephalopods belonging to the subclass Nautiloidea that began in the Late Cambrian and are represented today by the living Nautilus. Nautiloids flourished during the early Paleozoic era, where they constituted the main predatory animals, and...

, that lived in what would be North America

North America

North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

 during the Ordovician

Ordovician

The Ordovician is a geologic period and system, the second of six of the Paleozoic Era, and covers the time between 488.3±1.7 to 443.7±1.5 million years ago . It follows the Cambrian Period and is followed by the Silurian Period...

 from 460.5—449 mya, existing for approximately .

Taxonomy

Narthecoceratidae was named by Flower (1958). It was assigned to Endocerida by Teichert et al. (1964); and to Orthocerida

Orthocerida

Orthocerida is an order of extinct nautiloid cephalopods also known as the Michelinocerda that lived from the Early Ordovician possibly to the Late Triassic . A fossil found in the Caucasus suggests they may even have survived until the Early Cretaceous...

by Frey (1981).

Morphology

The shell is usually long, and may be straight ("orthoconic

Orthocone

An orthocone is a usually long straight shell of a nautiloid cephalopod. During the 18th and 19th centuries, all shells of this type were named Orthoceras, but it is now known that many groups of nautiloids developed or retained this type of shell....

") or gently curved. In life, these animals may have been similar to the modern squid

Squid

Squid are cephalopods of the order Teuthida, which comprises around 300 species. Like all other cephalopods, squid have a distinct head, bilateral symmetry, a mantle, and arms. Squid, like cuttlefish, have eight arms arranged in pairs and two, usually longer, tentacles...

, except for the long shell.

Fossil distribution

Fossil distribution includes Ohio

Ohio

Ohio is a Midwestern state in the United States. The 34th largest state by area in the U.S.,it is the 7th‑most populous with over 11.5 million residents, containing several major American cities and seven metropolitan areas with populations of 500,000 or more.The state's capital is Columbus...

, Franklin District, Canada

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

, and Manitoba, Canada.