Canadaspis 4325458 222114935 2008-06-27T17:03:33Z Rudolf Pohl 5573831 The Chengjiang fauna is older - see article "Maotianshan Shale" {{Taxobox | status=Fossil | name = ''Canadaspis'' | fossil_range = [[Cambrian]] | image = Canadaspis_perfecta.JPG | image_caption = ''Canadaspis perfecta'' & ''[[Waptia]] fieldensis'' | regnum = [[Animal]]ia | phylum = [[Arthropod]]a | subphylum = [[Crustacea]] | classis = ?[[Malacostraca]] | ordo = [[Canadaspidida]] | familia = [[Canadaspididae]] | genus = '''''Canadaspis''''' | genus_authority = [[Derek Briggs|Briggs]], 1978 | subdivision_ranks = Species | subdivision = * ''C. perfecta'' * ''C. laevigata'' | type_species = ''C. perfecta'' }} '''''Canadaspis''''' ("Shield of Canada") was a [[Cambrian]] [[genus]] of [[crustacean]] or [[euarthropod]], a benthic feeder that moved mainly by walking and possibly used its [[biramous]] [[appendage]]s to stir mud in search of food. The genus is placed within subclass [[Phyllocarida]] in class [[Malacostraca]] that includes shrimps and lobsters. Once the food was obtained, ''Canadaspis'' used its [[Mandible (arthropod)|mandibles]] to grind larger particles. It is possible that its gill flaps were used for locomotion. ''Canadapsis perfecta'', the type species, comes from the Cambrian-age [[Burgess Shale]] in [[British Columbia]], [[Canada]]. ''Canadaspis'' are also found in different formations of the [[House Range]] of western [[Utah]] as well as the [[Pioche Shale]] of [[Nevada]]. ''Canadaspis laevigata'', coming from the [[Chengjiang biota]] and thus some 10 million years older than ''Canadapsis perfecta'', is an equivocal member of the genus. Some scientists believe ''Canadaspis laevigata'' to be a more primitive [[Crustaceomorpha]] antecedent of ''Canadaspis'', and others consider it a bi-valved [[arthropod]] of uncertain affinity. The [[phylogeny]] of ''Canadaspis'', like many Cambrian [[arthropods]] is in a state of flux. ==References== *{{cite web |url=http://www.nmnh.si.edu/paleo/shale/pcanadap.htm |publisher=[[National Museum of Natural History]] |accessdate=11 May |accessyear= 2006 |title=''Canadapsis perfecta'' (a crustacean)}} *{{cite journal |quotes=no |author=[[Derek Briggs|Briggs, D.]] |year=1978 |title=The morphology, mode of life, and affinities of ''Canadaspis perfecta'' (Crustacea: Phyllocarida), Middle Cambrian, Burgess Shale, British Columbia |journal=[[Philosophical Transactions of the Royal Society|Phil. Trans. R. Soc. Lond. B]] |volume=281 |issue=984 |pages=439–487 |doi=10.1098/rstb.1978.0005}} *{{cite web |url=http://www.fossilmuseum.net/ |publisher=The Virtual Fossil Museum |title=''Canadaspis'' from Chengjiang and Utah |accessdate=28 September |accessyear=2006}} *{{cite journal |quotes=no |url=http://jpaleontol.geoscienceworld.org/cgi/content/abstract/77/4/674 |author=Lieberman, A. |year=2003 |title=New Soft-Bodied Fauana: The Pioche Formation of Nevada |journal=Journal of Paleontology |volume=77 |issue=4 |pages=674–690 |doi=10.1666/0022-3360(2003)077<0674:ANSFTP>2.0.CO;2 |doilabel=10.1666/0022-3360(2003)077&#60;0674:ANSFTP&#62;2.0.CO;2}} [[Category:Prehistoric arthropods]] [[Category:Burgess Shale fossils]] [[Category:Maotianshan shales fossils]] {{crustacean-stub}} [[ca:Canadaspis]] [[es:Canadaspis]] [[ja:カナダスピス]]