Spirulida is an

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

cephalopod 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 ...

s comprising one

extant Extant or Least-concern species, least concern is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Exta ...

species (''

Spirula spirula ''Spirula spirula'' is a species of deep-water squid-like cephalopod mollusk. It is the only extant member of the genus ''Spirula'', the family Spirulidae, and the order Spirulida. Because of the shape of its internal shell, it is commonly known ...

'') and several

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

taxa In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

Fossil record

* Oldest representative: Carboniferous, though contested: see ''

Shimanskya ''Shimanskya'' is a late Carboniferous fossil tentatively interpreted as an early spirulid. This identification was based on: Doguzhaeva ''et al.'' also identify these features in living Spirula, and the fossil 'Spirulida' Naefia, ''Groenlandi ...

'' * Oldest uncontested representative: Late Jurassic

Classification

Taxa marked with † are extinct. *Order Spirulida ***Family †

Shimanskyidae ''Shimanskya'' is a late Carboniferous fossil tentatively interpreted as an early spirulid. This identification was based on: Doguzhaeva ''et al.'' also identify these features in living Spirula, and the fossil 'Spirulida' Naefia, ''Groenlandi ...

**Suborder †Groenlandibelina Khromov, 1990 ***Family †

Groenlandibelidae Groenlandibelidae is an extinct family of coleoid cephalopods believed to belong to the spirulids. Morphologically, its taxa seem to have some belemnoid characteristics, suggesting a possible intermediate relationship. Genera ''Groenlandibe ...

***Family †

Adygeyidae ''Adygeya'' is a genus of cephalopods assigned to the Spirulida Spirulida is an order of cephalopods comprising one extant species ('' Spirula spirula'') and several extinct Extinction is the termination of an organism by the death of ...

**Suborder †Belopterina Engeser, 1998 ***Family † Belemnoseidae ***Family † Belopteridae **Suborder Spirulina Pompeckj, 1912 ***Family † Spirulirostridae ***Family † Spirulirostrinidae ***Family Spirulidae

References

Tree of Life: SpirulidaThe Taxonomicon: Order Spirulida
{{Taxonbar, from=Q1370442 Cephalopod orders Cenozoic cephalopods