THE SUB-PHYLUM CRUSTACEAN is one of the largest groups in the phylum Arthropods .The sub phylum is divided into several classes, the most important of which are Malacostraca and cirripedia . The class Malacostraca includes crayfish,crabs,lobsters,, and shrimps.Typical features of Malacostracans include a body divided into two sections (a combined head and thorax , and no abdomen );an exoskeleton
(external skeleton) with a large plate( carapace) covering celhalothorax;stalked, compound eyes ; and two parts of antennae .The class Cirripedia includes barnacles, which , unlike other Crustaceans, spend their adult lives attached to a surface , such as rocks .Other characteristics of Cirripedes include an exoskeleton of overlapping calcareous plates;a body consisting almost entirely of thorax (the abdomen and head are minute); and six parts of thoracic appendages (cirri) used for filter feeding.
The main Crustaceans are CRABS, SHRIMPS.CRAYFISH,
BARNACLE.
CRUSTACEANS
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(external skeleton) with a large plate( carapace) covering celhalothorax;stalked, compound eyes ; and two parts of antennae .The class Cirripedia includes barnacles, which , unlike other Crustaceans, spend their adult lives attached to a surface , such as rocks .Other characteristics of Cirripedes include an exoskeleton of overlapping calcareous plates;a body consisting almost entirely of thorax (the abdomen and head are minute); and six parts of thoracic appendages (cirri) used for filter feeding.
The main Crustaceans are CRABS, SHRIMPS.CRAYFISH,
BARNACLE.
CRUSTACEANS
9
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