Peracarida

crustacean

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July 1, 2026

Quick Summary

Peracarida is a division of crustaceans within the subclass Eumalacostraca. This group is characterized by a shortened carapace that is either attached anteriorly to the thorax or absent altogether. A key feature of Peracarida is that their eggs develop within a ventral thoracic brood pouch, and they hatch as miniature adults.12

This division includes well-known crustaceans such as amphipods and isopods. Peracarids are found in diverse environments, from marine and freshwater habitats to terrestrial settings.12

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Peracarida
malacostracan - Annotated classification

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crustacean
Annotated classification
Superorder PeracaridaFemales with a ventral brood pouch formed by plates at the bases of some of the thoracic limbs; development direct, with offspring resembling adults.Order Mysidacea (opossum shrimps)Triassic to present; carapace well-developed, covering most of thorax; 3–30 mm, with a few much larger;…
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Superorder PeracaridaFemales with a ventral brood pouch formed by plates at the bases of some of the thoracic limbs; development direct, with offspring resembling adults.Order Mysidacea (opossum shrimps)Triassic to present; carapace well-developed, covering most of thorax; 3–30 mm, with a few much larger;…
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malacostracan
Annotated classification
Superorder Peracarida Carapace shortened, attached anteriorly to thorax, or lacking; eggs develop in ventral thoracic brood pouch and hatch as miniature adults. ^†Order Pygocephalomorpha Carboniferous to Permian; carapace large, unridged, covering thorax; ventral plates of thorax widening behind; walking legs 6-segmented; abdomen 6-segmented; coastal
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Superorder Peracarida Carapace shortened, attached anteriorly to thorax, or lacking; eggs develop in ventral thoracic brood pouch and hatch as miniature adults. ^†Order Pygocephalomorpha Carboniferous to Permian; carapace large, unridged, covering thorax; ventral plates of thorax widening behind; walking legs 6-segmented; abdomen 6-segmented; coastal
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