- Nectaspida
Taxobox
name = Nectaspida
image_caption = "Naraoia spinosa"
fossil_range =Cambrian toSilurian
regnum =Animal ia
phylum =Arthropod a
classis =Trilobita †
ordo = Nectaspida†
ordo_authority = Raymond, 1920
subdivision_ranks = Families
subdivision =Liwiidae †Naraoiidae †The Nectaspida (also called Naraoiida, Nectaspia and Nektaspida) is an extinct order of soft-bodied
arthropod s proposed by Raymond in 1920; its taxonomic status is uncertain. Specimens are known from the earlyCambrian to the upperSilurian periods. Whittington (1985) placed the order in the Trilobita. Cotton & Braddy (2000) place it in a new "Trilobite clade " containing the Trilobita, recognizing the close affinities of the Nectaspids to trilobites. Others consider the small number of genera in the Nectaspida unworthy of ordinal status.Naming history
The order was originally proposed by Raymond in 1920 as Nectaspia. Størmer corrected it to Nectaspida for the 1959 "
Treatise on Invertebrate Paleontology " to conform with the names of the other trilobite orders. Whittington described it in 1985 with the spelling Nektaspida; the revised 1997 Treatise by Raymond and Fortey uses this spelling.External links
* [http://www.trilobites.info/naraoia.htm Are Naraoids trilobites?] -- photographs of specimens and discussion of classification controversy.
* [http://www.peripatus.gen.nz/Taxa/Arthropoda/Trilobita/Nectaspida.html Order Nectaspida] -- more technical overview with references and descriptions of known genera.
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