Syncarida
Quick Summary
Syncarida is a superorder of crustaceans, characterized by the absence of a carapace. This group is part of the class Malacostraca, which is the largest class within the subphylum Crustacea. Syncaridans typically have a body plan with a distinct thorax and abdomen, and their thoracic legs are biramous, meaning they have two branches, and bear gills but lack pincer claws.123
The superorder Syncarida includes several orders, such as Palaeocaridacea (extinct), Anaspidacea, Stygocaridacea, and Bathynellacea. While most syncarids are small, some species can reach lengths of up to 10 centimeters. They are found in various aquatic environments, including freshwater habitats like groundwaters and subterranean spaces.234
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crustaceanAnnotated classificationSuperorder SyncaridaCarboniferous to present; no carapace.†Order PalaeocaridaceaCarboniferous to Permian; first thoracic segment not fused to head; abdominal pleopods 2-branched, flaplike; 4 families.Order AnaspidaceaPermian to present; with or without eyes; antennules
Read MoreSuperorder SyncaridaCarboniferous to present; no carapace.†Order PalaeocaridaceaCarboniferous to Permian; first thoracic segment not fused to head; abdominal pleopods 2-branched, flaplike; 4 families.Order AnaspidaceaPermian to present; with or without eyes; antennules
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malacostracanAnnotated classificationSuperorder Syncarida Late Devonian to Holocene; carapace lacking; thorax and abdomen weakly separated; thoracic legs biramous, bearing gills but without pincer claws; abdomen 6-segmented; 150 species. †Order Palaeocaridacea Carboniferous to Permian; first thoracic segment not fused to head; abdominal pleopods 2-branched, flaplike; 4 families.
Read MoreSuperorder Syncarida Late Devonian to Holocene; carapace lacking; thorax and abdomen weakly separated; thoracic legs biramous, bearing gills but without pincer claws; abdomen 6-segmented; 150 species. †Order Palaeocaridacea Carboniferous to Permian; first thoracic segment not fused to head; abdominal pleopods 2-branched, flaplike; 4 families.
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