Orthoceratidae, is an extinct family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 of actively mobile carnivorous cephalapods, subclass Nautiloidea, 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...

, Europe

Europe

Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...

, Asia

Asia

Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...

, Africa

Africa

Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...

, and Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 from 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...

 through Triassic

Triassic

The Triassic is a geologic period and system that extends from about 250 to 200 Mya . As the first period of the Mesozoic Era, the Triassic follows the Permian and is followed by the Jurassic. Both the start and end of the Triassic are marked by major extinction events...

 from 490—203.7 mya, existing for approximately .

Taxonomy

Orthoceratidae was named by McCoy (1844) and assigned to the Orthocerida by Teichert and Miller (1939),(as Orthocerotidae); to the Michelinoceratida by Flower (1962), and to the Orthocerataceae by Sweet (1964). It has been subsequently included in the Orthocerataceae in Evans (1994) and in the Orthocerida in Evans (2005) and in Kröger et al. (2007) Flower showed in 1962 that Orthocerotidae used by Teichert and Miller (1939) is synonymous with Orthoceratide McCoy (1884)

Morphology

Members are characterised by long, slender, usually 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....

 (straight) but sometimes slightly-curved shells, a central or subcentral orthochoanitic siphuncle

Siphuncle

The siphuncle is a strand of tissue passing longitudinally through the shell of a cephalopod mollusk. Only cephalopods with chambered shells have siphuncles, such as the extinct ammonites and belemnites, and the living nautiluses, cuttlefish, and Spirula...

 that is free of deposits, a long body chamber

Body chamber

The body chamber, also called the living chamber, is the outermost or last chamber in the shell of a nautiloid or ammonoid cephalopod. The body of the animal occupies the living chamber, apart from the siphuncle which extends through the rest of septa to provide buoyancy....

, and cylindrical or only slightly-inflated connecting rings. Ornamentation may be in the form of longitudinal or transverse ribs and/or lirae, or the shell surface may be smooth.