Prehistoric cephalopod genera

Endoceras, from Ancient Greek ἔνδον (éndon), meaning "inside", and κέρας (kéras), meaning "horn", is an extinct genus of large, straight-shelled cephalopods that gives its name to the Nautiloid order Endocerida. The genus lived during the middle and upper Ordovician 470 to 443 million years ago. The cross section in the mature portion is slightly wider than high, but is narrower laterally in the young. Sutures are straight and transverse. Endoceras has a large siphuncle, located close to the ventral margin, composed of concave segments, especially in the young but which may be tubular in the a

Keuppia is an extinct genus of octopus.

fossil genus of molluscs

Turrilites is a genus of helically coiled ammonoid cephalopods from the lower part of the Upper Cretaceous (Cenomanian and Turonian); generally included in the Ancyloceratina. Previously (Arkell, 1957) it was included in the ammonoid suborder, Lytoceratina.

Enchoteuthis (meaning "spear squid") is an extinct genus of large enchoteuthine cephalopod that lived during the Cretaceous. Although it and its relative Tusoteuthis are often compared to squid, both are now thought to be more closely related to modern octopuses. Examination of gladius remains initially yielded an estimated mantle length of about based on one specimen once described as Tusoteuthis longa, which is close to or equal to that of the modern giant squid, although reclassification of this genus as a muensterelloid results in a longer total length, about . Three species are currently

Belemnitella is a genus of belemnite from the Late Cretaceous of Europe and North America.

extinct genus of cephalopods

Belemnotheutis is an extinct coleoid cephalopod genus from the middle and upper Jurassic, related to but morphologically distinct from belemnites. Belemnotheutis fossils are some of the best preserved among coleoids. Remains of soft tissue are well-documented in some specimens, even down to microscopic muscle tissue. In 2008, a group of paleontologists even recovered viable ink from ink sacs found in several specimens.

Hibolithes is a genus of belemnite that lived from the Middle Jurassic to the Early Cretaceous, and has been found in Antarctica, Greenland, Iran, Europe, South America, and New Zealand. In 2020, this genus was found in the Pedawan Formation (Tithonian – Hauterivian) in Sarawak, on the island of Borneo (Malaysia).

Acanthodiscus is an extinct ammonoid cephalopod genus from the order Ammonitida and included in the persphinctacean family Berriasellidae. The type species, named by Bruguière, 1792, is Acanthodiscus radiatus.

Acroteuthis is a genus of belemnite from the early Cretaceous of Asia, Europe, and North America.

Cylindroteuthis is a genus of belemnite that lived from the Early Jurassic to the Early Cretaceous. Its fossils have been found in Asia, Europe, North America, and New Zealand.