Superorder PERACARIDA Calman, 1904
Compiler and date details
2002, 2003 - James K. Lowry & Gary C.B. Poore
Introduction
Peracaridans are malacostracan crustaceans that brood their eggs and young in a marsupium under the thorax formed by branches of some of the pereopods, and that have a lacinia mobilis on the mandible. The only exception to this widely accepted definition are the Thermosbaenacea which brood their eggs under a dorsal carapace.
In this database, as in Poore (2002) and Lowry & Stoddart (2003), the Peracarida are considered to comprise eight orders: Amphipoda, Cumacea, Isopoda, Mictacea, Mysidacea, Spelaeogriphacea, Tanaidacea and Thermosbaenacea. There has been little debate until recently about the composition of the Peracarida, but recent evidence suggests the traditional arrangement used here may be artificial. It concerns the position of the Mysida, conventionally placed with the Lophogastrida, in one order, Mysidacea. Molecular phylogenetic data, supported by reinterpretation of morphology, now suggests the Mysida are an order within Eucarida, not at all related to Lophogastrida (Spears & Abele 1998; Watling 1999; Jarman et al. 2000).
The evolution of the orders, with or without the Mysida, has been long discussed (Hessler & Watling 1999). Several cladograms based on various intuitive and cladistic methods have been published, each suggesting different relationships (Siewing 1963; Watling 1983; Schram 1986; Wills 1998; Wheeler 1998). None until recently have suggested that the orders themselves might not be monophyletic. Gutu (1998) and Gutu & Illiffe (1998) placed Spelaeogriphacea and the mictacean family Mictocarididae in a new order, Cosinzeneacea and assigned Hirsutiidae from Mictacea to another new order, Bochusacea. Their proposals have not yet been accepted by other taxonomists.
Diagnosis
Eggs incubated in a subthoracic marsupium formed by oostegites originating from pereopodal coxae; young enclosed until an advanced stage, either as juveniles or subjuveniles (mancas) with undeveloped posterior pereopods; mandible with an articulating lacinia mobilis; thoracopod 1 modified as a maxilliped; thoracomere 1 fused to cephalon; carapace (if present) never fused to all thoracomeres; pereopods with most pronounced flexure between carpus and propodus; coxa very weakly articulating with body.
General References
Gutu, M. 1998. Spelaeogriphacea and Mictacea (partim) suborders of a new order, Cosinzeneacea (Crustacea, Peracarida). Travaux du Muséum d'Histoire Naturelle "Grigore Antipa" 40: 121-129
Gutu, M. & Iliffe, T.M. 1998. Description of a new hirsutiid (n. g., n. sp.) and reassignment of this family from Order Mictacea to the new order, Bochusacea (Crustacea, Peracarida). Travaux du Muséum d'Histoire Naturelle "Grigore Antipa" 40: 93-120
Jarman, S.N., Nicol, S., Elliott, N.G. & McMinn, A. 2000. 28rDNA evolution in the Eumalacostraca and the phylogenetic position of krill. Molecular Phylogenetics and Evolution 17: 26-36
Schram, F.R. 1986. Crustacea. New York : Oxford University Press xii 606 pp.
Spears, T. & Abele, G. 1998. Crustacean phylogeny inferred from 18S rDNA. pp. 169-188 in Fortey, R.A. & Thomas, R.H. (eds). Arthropod relationships. The Systematics Association Special Volume Series. London : Chapman & Hall Vol. 55.
van Klinken, R.D. & Green, A.J.A. 1992. The first record of Oniscidea (terrestrial Isopoda) from Macquarie Island. Polar Record 28: 240-242
Watling, L. 1999. Toward understanding the relationships of the peracaridan orders: the necessity of determining exact homologies. pp. 73-89 in Schram, F.R. & Vaupel Klein, J.C.von (eds). Crustaceans and the biodiversity crisis. Proceedings of the Fourth International Crustacean Congress, Amsterdam, The Netherlands, July 20-24, 1998. Leiden : Brill Vol. 1.
Watson, M. 2003. [unpublished data]. (in prep.).
Wheeler, W.C. 1998. Sampling, groundplans, total evidence and the systematics of arthropods. pp. 87-96 in Fortey, R.A. & Thomas, R.H. (eds). Arthropod relationships. The Systematics Association Special Volume Series. London : Chapman & Hall Vol. 55.
Wills, M.A. 1998. A phylogeny of recent and fossil Crustacea derived from morphological characters. pp. 189-210 in Fortey, R.A. & Thomas, R.H. (eds). Arthropod relationships. The Systematics Association Special Volume Series. London : Chapman & Hall Vol. 55.
History of changes
| Published | As part of group | Action Date | Action Type | Compiler(s) |
|---|---|---|---|---|
| 26-Feb-2019 | MODIFIED |