Isopoda.

See full text attached .... Isopods are often common and important members of many marine habitats. They can be distinguished from other peracarids, and other crustaceans in general, by the following combination of characteristics: 1. Body usually flattened (except in Anthuridea and Phreatoicidea).... 2. Head (cephalon) compact, with unstalked compound eyes, two pairs of antennae (first pair minute in Oniscidea), and mouthparts comprising a pair of mandibles, two pairs of maxillae (maxillules and maxillae), and one pair of maxillipeds. 3. A long thorax of eight thoracomeres, the first (and also the second in Gnathiidea) fused with the head and bearing the maxillipeds, the remaining seven (called pereonites) being free and collectively comprising a body division called the pereon. 4. Seven pairs of uniramous legs (pereopods), all more or less alike (hence, "iso-pod"), except Gnathiidea, which have only five pairs of walking legs. 5. Appendages never chelate (i.e., the subterminal article, or propodus, is not modified into "hand" that works with the terminal article, or dactyl, as a true claw).