- Eumalacostraca
image_width = 250px
image_caption =Blue crab s, "Callinectes sapidus"
regnum =Animal ia
phylum =Arthropod a
subphylum = Crustacea
classis =Malacostraca
subclassis = Eumalacostraca
subclassis_authority = Grobben, 1892
subdivision_ranks = Superorders
subdivision =Syncarida Peracarida Eucarida See text for orders.The Eumalacostraca (Greek: "true soft shell") are a subclass of
crustacean s, containing almost all livingmalacostraca ns, about 22,000 described species. (The outgroups are thePhyllocarida and possibly theHoplocarida or mantis shrimps.)Eumalacostracans have 19 segments (5 cephalic, 8 thoracic, 6 abdominal). The thoracic limbs are jointed and used for swimming or walking. The common ancestor is thought to have had a
carapace , and most living species possess one, but it has been lost in some subgroups.Classification
Martin and Davis [cite book|author = J. W. Martin & G. E. Davis|url = http://www.nhm.org/research/publications/CrustaceaClassification.pdf |title=An Updated Classification of the Recent Crustacea|year = 2001|publisher =
Natural History Museum of Los Angeles County ] present the following classification of living eumalacostracans into orders, to which extinct orders have been added, indicated by †.The group as originally described by
Karl Grobben [cite journal|quotes=no |author = C. Grobben|year = 1892|title = Zur Kenntnis des Stammbaumes und des Systems der Crustaceen|journal = Sitzber. K. Akad. Wiss., Vienna, Math. Nat. Cl.|volume = 101|pages = 237–274] included theStomatopoda (mantis shrimp), and some modern experts continue to use this definition. Here we follow Martin and Davis in excluding them; they are placed in their own subclass,Hoplocarida .Subclass Eumalacostraca Grobben, 1892
* SuperorderSyncarida Packard, 1885
** †OrderPalaeocaridacea
** OrderBathynellacea Chappuis, 1915
** OrderAnaspidacea Calman, 1904 (including Stygocaridacea)
* SuperorderPeracarida Calman, 1904
** OrderSpelaeogriphacea Gordon, 1957
** OrderThermosbaenacea Monod, 1927
** OrderLophogastrida Sars, 1870
** OrderMysida Haworth, 1825
** OrderMictacea Bowman, Garner, Hessler, Iliffe & Sanders, 1985
** OrderAmphipoda Latreille, 1816
** OrderIsopoda Latreille, 1817 (pillbugs, sowbugs, woodlice)
** OrderTanaidacea Dana, 1849
** OrderCumacea Krøyer, 1846
* SuperorderEucarida Calman, 1904
** OrderEuphausiacea Dana, 1852
** Order Amphionidacea Williamson, 1973
** OrderDecapoda Latreille, 1802 (crabs, lobsters, shrimp)References
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