''Tommotia'' is a small shelly fossil from the Early

Cambrian The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million ...

Period. Originally, only a cone-shaped shell was recognized, which was originally thought to be an early

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

, with either

squid True squid are molluscs with an elongated soft body, large eyes, eight arms, and two tentacles in the superorder Decapodiformes, though many other molluscs within the broader Neocoleoidea are also called squid despite not strictly fitting t ...

-like tentacles or a

snail A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class Gastro ...

-like foot. More recent investigation has shown that the cone is not the remains of a complete animal, but a sclerite of a larger, soft-bodied animal that would have resembled a

chiton Chitons () are marine molluscs of varying size in the class Polyplacophora (), formerly known as Amphineura. About 940 extant and 430 fossil species are recognized. They are also sometimes known as gumboots or sea cradles or coat-of-mail s ...

or a

sea mouse ''Aphrodita'' is a genus of marine polychaete worms found in the Mediterranean sea and the eastern and western Atlantic Ocean. Several members of this genus are known as "sea mice". Etymology The name of the genus is taken from Aphrodite, ...

. The fossils called ''Camanella'' may be another type of sclerite from the same animal.

References

External links

The Tommotian Age of the Early Cambrian Epoch
Cambrian animals of Asia Enigmatic animal taxa Fossil taxa described in 1966 {{paleo-mollusc-stub Cambrian genus extinctions