''Sphooceras'' is a genus of primitive cephalopod from the

Silurian The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at million years ago (Mya), to the beginning of the Devonian Period, Mya. The Silurian is the shortest period of the Paleozoi ...

period. Most fossils have been found in the

Czech Republic The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. Th ...

, but possible fossils may also exist in other countries. It is currently known from two species, ''Sphooceras disjunctum'' and ''Sphooceras truncatum''.

Description

Multiple individuals of ''Sphooceras'' have been found, possibly even sporting various growth stages. While the larvae sported coiled shells, adult individuals were found have sported

truncated Truncation is the term used for limiting the number of digits right of the decimal point by discarding the least significant ones. Truncation may also refer to: Mathematics * Truncation (statistics) refers to measurements which have been cut of ...

, straight shells, giving them a rather sausage-like appearance. They are among the earliest

cephalopods A cephalopod is any member of the molluscan Taxonomic rank, class Cephalopoda (Greek language, Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral symm ...

to sport a fully-covered mantle, similar to that of a

cowrie Cowrie or cowry () is the common name for a group of small to large sea snails, marine gastropod mollusks in the family Cypraeidae, the cowries. The term ''porcelain'' derives from the old Italian term for the cowrie shell (''porcellana' ...

, and may have even repaired such shells similarly. Fossilized remains also show possible patterning of stripes similar to those sported on the extant

nautilus The nautilus (, ) is a pelagic marine mollusc of the cephalopod family Nautilidae. The nautilus is the sole extant family of the superfamily Nautilaceae and of its smaller but near equal suborder, Nautilina. It comprises six living species ...

, probably for

camouflage Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the b ...

References

Prehistoric cephalopod genera Fossil taxa described in 1860 Orthocerida {{Paleo-cephalopod-stub