''Cambrorhytium'' is an enigmatic fossil genus known from the Latham Shale (California), and the Chengjiang (China) and

Burgess Shale The Burgess Shale is a fossil-bearing deposit exposed in the Canadian Rockies of British Columbia, Canada. It is famous for the exceptional preservation of the soft parts of its fossils. At old (middle Cambrian), it is one of the earliest fos ...

(Canadian rockies)

lagerstätte A Fossil-Lagerstätte (, from ''Lager'' 'storage, lair' '' Stätte'' 'place'; plural ''Lagerstätten'') is a sedimentary deposit that preserves an exceptionally high amount of palaeontological information. ''Konzentrat-Lagerstätten'' preserv ...

. 350 specimens of ''Cambrorhytium'' are known from the Greater

Phyllopod bed The Phyllopod bed, designated by USNM locality number 35k, is the most famous fossil-bearing member of the Burgess Shale fossil ''Lagerstätte''. It was quarried by Charles Walcott from 1911–1917 (and later named Walcott Quarry), and was ...

, where they comprise 0.7% of the community.

Etymology

Its name is from the Latin ''rhytium'', drinking horn.

Description

The fossil is conical, with iterated linear markings on its walls, parallel to its base. Its wall is thin, and it lacks the keel that is distinctive of

hyolith Hyoliths are animals with small conical shells, known from fossils from the Palaeozoic era. They are at least considered as being lophotrochozoan, and possibly being lophophorates, a group which includes the brachiopods (hyoliths may even be ...

s. It has been interpreted as a

cnidarian Cnidaria ( ) is a phylum under kingdom Animalia containing over 11,000 species of aquatic invertebrates found both in fresh water, freshwater and marine environments (predominantly the latter), including jellyfish, hydroid (zoology), hydroids, ...

polyp, with the interpretation suggesting that the animal lived in the tube and extended tentacles (of which no trace has been found) from the flat aperture. This is supported by similarities to Palaeoconotuba. The other possible, but probably unlikely, affinity is with the hyoliths. Its similarity with the Lower Cambrian species '' Torellelloides giganteum'' may indicate a close relationship. ''Cambrorhytium'' has also been compared to the fossil '' Archotuba'' and '' Sphenothallus''. ''C. elongatum'' has been described to contain an alimentary canal in a single Chinese specimen.

Taxonomy

''C. major'' was originally described as a member of the

genus '' Orthotheca''. ''C. fragilis'' was originally included by Charles D. Walcott in the genus '' Selkirkia'', – a taxonomy that was retained by later workers until finally questioned and redescribed as ''Cambrorhytium'' in the eighties.

References

External links

* Burgess Shale fossils Staurozoa Burgess Shale animals Prehistoric cnidarian genera Controversial taxa Fossil taxa described in 1908 Cambrian genus extinctions {{paleo-staurozoa-stub