Naraoiidae 21214 191848835 2008-02-16T13:51:34Z Eubot 231599 Removed taxobox colour. See [[User:Eubot/Removing colours from taxoboxen]]. {{Taxobox | name = Naraoiidae | image = Naraoia_spinosa.jpg | image_caption = ''Naraoia spinosa'' | fossil_range = [[Cambrian]]–[[Silurian]] | regnum = [[Animal]]ia | phylum = [[Arthropod]]a | classis = [[Trilobita]]&dagger; | ordo = [[Nectaspida]] | familia = '''Naraoiidae''' | familia_authority = [[Charles Doolittle Walcott|Walcott]], 1912 | subdivision_ranks = Genera | subdivision = ''[[Misszhouia]]''&dagger;<br /> ''[[Naraoia]]''&dagger;<br /> }} The '''Naraoiidae''' is a [[family (biology)|family]] of soft-shelled [[trilobite]]-like [[arthropod]]s that are known only from the early and middle [[Cambrian]] -- primarily from the [[Burgess Shale]] of [[British Columbia]] and the [[Maotianshan Shale]] of [[China]]. The taxonomic placement of the Naraoiidae is uncertain; Naraoiids are similar to trilobites in many ways but have several peculiar features unlike those of other trilobite groups, primarily their unmineralized [[exoskeleton]] and unsegmented . Some specialists consider the Naraoiidae true trilobites of the order [[Nectaspida]], others consider them trilobites of uncertain ordinal status, and still others consider them a separate group of non-trilobite arthropods. There are several known [[Genus|genera]], of which ''Naraoia'' was the first to be described and is the most widely known. The species ''Naraoia naraoia'' has an entirely unmineralized body covering and an unsegmented shield. Its maximum size is about 4 cm. A second softbodied trilobite - ''[[Tegopelte]]'' - is known from the same formations and is sometimes placed in the Naraoiidae and sometimes in its own family, the Tegopeltidae. ==External links== *[http://www.trilobites.info/naraoia.htm Are Naraoids trilobites?] Photographs of specimens and discussion of classification controversy [[Category:Prehistoric arthropods]] [[Category:Trilobites]] [[fr:Naraoiidae]]