The exact relationships of the Crustacea to other taxa are not completely settled as of April2012 [update]. Studies based on morphology led to the Pancrustacea hypothesis, [46] in which Crustacea and Hexapoda ( insects and allies) are sister groups. More recent studies using DNA sequences suggest that Crustacea is paraphyletic, with the hexapods nested within a larger Pancrustacea clade. [47] [48] Elizabeth Pennisi (July 4, 1997). "Crab legs and lobster claws". Science. 277 (5322): 36. doi: 10.1126/science.277.5322.36. S2CID 83148200. Gollasch, Stephan (October 30, 2006). " Eriocheir sinensis" (PDF). Global Invasive Species Database. Invasive Species Specialist Group . Retrieved 2016-09-10. Antarctic Prehistory". Australian Antarctic Division. July 29, 2008. Archived from the original on September 30, 2009 . Retrieved February 25, 2010. Cephalothorax". Crustacean Glossary. Natural History Museum of Los Angeles County. Archived from the original on 2011-07-27 . Retrieved 2016-09-10.

The following cladogram shows the updated relationships between the different extant groups of the paraphyletic Crustacea in relation to the class Hexapoda. [52] Pancrustacea a b "Cephalon". Crustacean Glossary. Natural History Museum of Los Angeles County. Archived from the original on 2011-07-27 . Retrieved 2016-09-10. Srivastava, Shikha; Dahal, Sumedha; Naidu, Sharanya J.; Anand, Deepika; Gopalakrishnan, Vidya; Kooloth Valappil, Rajendran; Raghavan, Sathees C. (24 January 2017). "DNA double-strand break repair in Penaeus monodon is predominantly dependent on homologous recombination". DNA Research. 24 (2): 117–128. doi: 10.1093/dnares/dsw059. PMC 5397610. PMID 28431013. a b Schwentner, M; Combosch, DJ; Nelson, JP; Giribet, G (2017). "A Phylogenomic Solution to the Origin of Insects by Resolving Crustacean-Hexapod Relationships". Current Biology. 27 (12): 1818–1824.e5. doi: 10.1016/j.cub.2017.05.040. PMID 28602656.a b "Thorax". Crustacean Glossary. Natural History Museum of Los Angeles County. Archived from the original on 2011-07-27 . Retrieved 2016-09-10. OK, this guy clutching a decent quantity of tampons IS actually kind of cute. Yes? I mean, he LOOKS happy. Source: Reddit

a b c "FIGIS: Global Production Statistics 1950–2007". Food and Agriculture Organization . Retrieved 2016-09-10. H. J. Ceccaldi. Anatomy and physiology of digestive tract of Crustaceans Decapods reared in aquaculture (PDF). pp.243–259. {{ cite book}}: |work= ignored ( help) [ permanent dead link]

Crustaceans belong to the subphylum Crustacea ( / k r ə ˈ s t eɪ ʃ ə/), and form a large, diverse group of arthropods including decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, opossum shrimps, amphipods and mantis shrimp. [1] The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods ( insects and entognathans) emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. [2] The three classes Cephalocarida, Branchiopoda and Remipedia are more closely related to the hexapods than they are to any of the other crustaceans ( oligostracans and multicrustaceans). [3]