Eucarida

crustacean

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Last updated

June 26, 2026

Quick Summary

Eucarida is a large group of crustaceans that includes krill and decapods (like shrimp, lobsters, and crabs). A key characteristic of Eucarida is that their thoracic segments are covered by a carapace, and their eyes are on movable stalks. This group belongs to the subclass Malacostraca. Malacostracans, in general, have double or triple-branched antennules and often possess pincers on their walking limbs. They also exhibit thoracic and abdominal respiration, and their terminal body segment has uropods.123

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Eucarida
crustacean - Annotated classification
malacostracan - Annotated classification

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crustacean
Annotated classification
Superorder Eucarida.Carapace large, fused dorsally to all thoracic segments; eyes stalked; development usually involves larval forms but is sometimes direct.Order Euphausiacea (krill)Holocene; carapace does not cover gills; thoracic limbs with 2 well-developed branches; eggs usually shed freely; first larva a nauplius; 6–81 mm;…
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Superorder Eucarida.Carapace large, fused dorsally to all thoracic segments; eyes stalked; development usually involves larval forms but is sometimes direct.Order Euphausiacea (krill)Holocene; carapace does not cover gills; thoracic limbs with 2 well-developed branches; eggs usually shed freely; first larva a nauplius; 6–81 mm;…
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malacostracan
Annotated classification
Superorder Eucarida Carapace fused to thorax; thoracic legs usually with gills at bases; eggs usually hatch as free-swimming larvae. ^†Order Belotelsonidea Carboniferous; carapace large; thoracic legs 1-branched, simple, without pincers; pleopods flaplike; telson with furcae; 1 family. Order Euphausiacea
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Superorder Eucarida Carapace fused to thorax; thoracic legs usually with gills at bases; eggs usually hatch as free-swimming larvae. ^†Order Belotelsonidea Carboniferous; carapace large; thoracic legs 1-branched, simple, without pincers; pleopods flaplike; telson with furcae; 1 family. Order Euphausiacea
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