Eumalacostraca

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Eumalacostraca

[yü‚mal·ə′käs·trə·kə]
(invertebrate zoology)
A series of the class Crustacea comprising shrimplike crustaceans having eight thoracic segments, six abdominal segments, and a telson.
References in periodicals archive ?
Evolutionary changes in the olfactory projection neuron pathways of eumalacostracan crustaceans.
2004) recorded 35 taxa in newly created intertidal mussel beds that resulted in more shore crabs Carcinus maenas, amphipods Melita palmata, and oligochaete worms Tubificoides benedeni, but fewer of the polychaetes Pygospio elegans and Notomastus latericeus, and the eumalacostracan Corophium spp.
1989) to analyze the segmentation of the embryonic pleon of a eumalacostracan, the Australian freshwater crayfish Cherax destructor.
This result confirms some of the suggestions of Manton (1928a, b), and since there is good evidence that the tail fans of all eumalacostracan groups are homologous (Hessler, 1983; Wagele, 1994), the findings presented here might also be valid for eumalacostracans in general.
subdivision of the terminal eumalacostracan segment, as was suggested earlier by Claus (1888).
There is no reason to assume that pedomorphosis led to the occurrence of the seventh segment in adult leptostracans and to the loss of the highly complex eumalacostracan tail-fan (Hessler, 1983; Paul et al.
On the basis of anatomical and paleontological data, Siewing (1956, 1963) argued that the uropods might be the appendages of the seventh pleomere and that the sixth (penultimate) pleomere has been lost in most eumalacostracans.
Adult eumalacostracans possess only six pleonic ganglia (see Hanstrom, 1928), and this is also true for leptostracans with a seventh pleomere (Claus, 1888; Manton, 1928a).