Palaeocaridacea
Quick Summary
The term Palaeocaridacea refers to an extinct order of crustaceans that existed from the Carboniferous to the Permian periods. These ancient crustaceans are classified within the subclass Syncarida, which is part of the larger class Malacostraca.1
Key characteristics of Palaeocaridacea include:
* The first thoracic segment was not fused to the head.1
* Their abdominal pleopods were two-branched and flaplike.1
The fossil record of Malacostraca, the group to which Palaeocaridacea belongs, extends back to the Early Ordovician period. While the fossil record provides evidence of their existence, the precise evolutionary origins and relationships of early crustaceans, including groups like Palaeocaridacea, are still subjects of scientific study.23
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crustaceanAnnotated classification†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 biramous; abdominal appendages well-developed; telson without a furca; South Australia and Tasmania; freshwater; about 8 species.
Read More†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 biramous; abdominal appendages well-developed; telson without a furca; South Australia and Tasmania; freshwater; about 8 species.
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malacostracanAnnotated classification†Order Palaeocaridacea Carboniferous to Permian; first thoracic segment not fused to head; abdominal pleopods 2-branched, flaplike; 4 families. Order Anaspidacea (torrent shrimps) Triassic to Holocene; first thoracic segment fused to head; pleopods 1-branched, slender, multisegmented; fresh waters of Australia, New Zealand, and
Read More†Order Palaeocaridacea Carboniferous to Permian; first thoracic segment not fused to head; abdominal pleopods 2-branched, flaplike; 4 families. Order Anaspidacea (torrent shrimps) Triassic to Holocene; first thoracic segment fused to head; pleopods 1-branched, slender, multisegmented; fresh waters of Australia, New Zealand, and
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