Belongs within: Eumalacostraca.
The Cumacea are a group of small marine crustaceans, less than 15 mm long. Their body shape is distinctive, with a globular anterior body and elongate pleon. Water is drawn into the gill cavity and passed forward through the pseudorostrum; most cumaceans feed by filtering food particles from the water.
Characters (from Ax 1999): Anterior body egg-shaped, pleon elongate, uropods pistil-like. Carapace extensive, covering several thoracic segments, paired lobes of carapace combining to form anterior pseudorostrum, posterior edge of carapace fused with body wall, with a narrow longitudinal slit ventrally; gill cavity formed by carapace containing two large epipodites from first gilled thoracopod pair. Antenna II without scaphocerite. Thoracopods I-III formed into maxillipeds. Pleopods I-V reduced in female.
<==Cumacea | i. s.: Mezolamprops japonicusGAS03 | CeratocumatidaeMD01 | OphthalmdiastylisBWW93 | Procampylaspis sordidaPG98 | Leucon pallidusS00 |--Pseudocuma [Pseudocumatidae]HKW04 | `--P. simile Sars 1900HKW04 `--+--Gynodiastylis [Gynodiastylidae]HKW04 | |--G. laevisPG98 | `--G. milleriHS01 `--DiastylidaeHKW04 |--OxyurostylisHKW04 | |--O. lecroyae Roccatagliata & Heard 1995HKW04 | `--O. smithi Roccatagliata & Heard 1995HKW04 `--+--+--DiastylopsisHKW04 | | |--D. crassiorPG98 | | `--D. thilenuisi (Zimmer 1902)HKW04 | `--Colurostylis longicaudata Jones 1963HKW04 `--+--DiastylisHKW04 | | i. s.: D. alaskensisGAS03 | | D. paralaskensisGAS03 | | D. politaC02 | |--D. bispinosa (Stimpson 1853)HKW04 | `--+--D. rathkei (Krøyer 1837)HKW04 | `--D. sculpta Sars 1871HKW04 `--+--LampropidaeHKW04 | |--Archaeocuma [Archaeocumatidae]HKW04 | |--HemilampropsHKW04 | | |--H. californicus Zimmer 1907HKW04 | | `--H. pellucidaPG98 | `--LampropsGAS03 | |--L. affinisGAS03 | |--L. fuscataS00 | |--L. multifasciataGAS03 | `--L. quadriplicatus Smith 1879HKW04 `--Bodotriidae [Bodotriinae, Vaunthompsoniinae]HKW04 | i. s.: AustrocumaHKW04 |--+--Pomacuma australiae (Zimmer 1921)HKW04 | `--+--Mancocuma [Mancocuminae]HKW04 | `--LeptocumaHKW04 `--+--NannastacidaeHKW04 | |--CumellaHKW04 | `--Campylaspis legendreiHKW04, M62 `--+--VaunthompsoniaHKW04 |--Eudorella [Leuconidae]HKW04 | `--E. pusilla Sars 1871HKW04 |--CyclaspisHKW04 | |--C. alba Roccatagliata 1986HKW04 | `--C. thomsoniHS01 |--EocumaHKW04 | |--E. feroxM62 | `--E. longicorne Calman 1907HKW04 `--+--IphinoeHKW04 | |--I. inermisPP64 | `--I. trispinosa (Goodsir 1843)HKW04 `--+--Cumopsis goodsir (Van Beneden 1861)HKW04 `--HeterocumaHKW04
*Type species of generic name indicated
References
Ax, P. 1999. Das System der Metazoa II. Ein Lehrbuch der phylogenetischen Systematik. Gustav Fisher Verlag: Stuttgart (translated: 2000. Multicellular Animals: The phylogenetic system of the Metazoa vol. 2. Springer).
[BWW93] Briggs, D. E. G., M. J. Weedon & M. A. Whyte. 1993. Arthropoda (Crustacea excluding Ostracoda). In: Benton, M. J. (ed.) The Fossil Record 2 pp. 321–342. Chapman & Hall: London.
[C02] Collette, B. B. 2002. Pricklebacks. Family Stichaeidae. In: Collette, B. B., & G. Klein-MacPhee (eds) Bigelow and Schroeder’s Fishes of the Gulf of Maine 3rd ed. pp. 474–481. Smithsonian Institute Press: Washington.
[GAS03] Gulbin, V. V., I. S. Arzamastsev & V. M. Shulkin. 2003. Ecological monitoring of the water area of Port Vostochnyi (Wrangel Bay) in the Sea of Japan (1995–2002). Russian Journal of Marine Biology 29 (5): 284–295.
[HKW04] Haye, P. A., I. Kronfield & L. Watling. 2004. Molecular insights into cumacean family relationships (Crustacea, Cumacea). Molecular Phylogenetics and Evolution 30: 798–809.
[HS01] Hayward, B. W., A. B. Stephenson, M. S. Morley, W. M. Blom, H. R. Grenfell, F. J. Brook, J. L. Riley, F. Thompson & J. J. Hayward. 2001. Marine biota of Parengarenga Harbour, Northland, New Zealand. Records of the Auckland Museum 37: 45–80.
[MD01] Martin, J. W., & G. E. Davis. 2001. An updated classification of the Recent Crustacea. Natural History Museum Los Angeles County, Science Series 39: 1–124.
[M62] Monniot, F. 1962. Recherches sur les graviers a Amphioxus de la région de Banyuls-sur-Mer. Vie et Milieu 13: 231–322.
[PP64] Peres, J. M., & J. Picard. 1964. Nouveau manuel de bionomie benthique de la mer Mediterranee. Recueil des Travaux de la Station Marine d’Endoume, Bulletin 31 (27): 5–137.
[PG98] Probert, P. K., & S. L. Grove. 1998. Macrobenthic assemblages of the continental shelf and upper slope off the west coast of South Island, New Zealand. Journal of the Royal Society of New Zealand 28: 259–280.
[S00] Stebbing, T. R. R. 1900. Arctic Crustacea: Bruce collection. Annals and Magazine of Natural History, series 7, 5: 1–16.