This list of edrioasteroids is an attempt to create a comprehensive listing of all genera from the fossil record that have ever been considered to be

edrioasteroid Edrioasteroidea is an extinct class of echinoderms. The living animal would have resembled a pentamerously symmetrical disc or cushion. They were obligate encrusters and attached themselves to inorganic or biologic hard substrates (frequently har ...

s, excluding purely vernacular terms. The list includes all commonly accepted genera, but also genera that are now considered invalid, doubtful ('' nomina dubia''), or were not formally published (''

nomina nuda In taxonomy, a ''nomen nudum'' ('naked name'; plural ''nomina nuda'') is a designation which looks exactly like a scientific name of an organism, and may have originally been intended to be one, but it has not been published with an adequate descr ...

''), as well as

junior synonyms The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linn ...

of more established names, and genera that are no longer considered edrioasteroids.

Naming conventions and terminology

Naming conventions and terminology follow the

International Code of Zoological Nomenclature The International Code of Zoological Nomenclature (ICZN) is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals. It is also informally known as the ICZN Code, for its publisher, the ...

. Technical terms used include: * Junior synonym: A name which describes the same taxon as a previously published name. If two or more genera are formally designated and the

type specimens In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralizes t ...

are later assigned to the same genus, the first to be published (in chronological order) is the senior synonym, and all other instances are junior synonyms. Senior synonyms are generally used, except by special decision of the ICZN, but junior synonyms cannot be used again, even if deprecated. Junior synonymy is often subjective, unless the genera described were both based on the same type specimen. *'' Nomen nudum'' (Latin for "naked name"): A name that has appeared in print but has not yet been formally published by the standards of the ICZN. ''Nomina nuda'' (the plural form) are invalid, and are therefore not italicized as a proper generic name would be. If the name is later formally published, that name is no longer a ''nomen nudum'' and will be italicized on this list. Often, the formally published name will differ from any ''nomina nuda'' that describe the same specimen. *'' Nomen oblitum'' (Latin for "forgotten name"): A name that has not been used in the scientific community for more than fifty years after its original proposal. *Preoccupied name: A name that is formally published, but which has already been used for another taxon. This second use is invalid (as are all subsequent uses) and the name must be replaced. As preoccupied names are not valid generic names, they will also go unitalicized on this list. *'' Nomen dubium'' (Latin for "dubious name"): A name describing a fossil with no unique diagnostic features. As this can be an extremely subjective and controversial designation, this term is not used on this list.

The list

References

* {{DEFAULTSORT:Edrioasteroid genera Lists of prehistoric echinoderms Prehistoric Crinozoa genera

Naming conventions and terminology

The list

See also

References