Phyllocarida
Quick Summary
Phyllocarida are a subclass of crustaceans belonging to the class Malacostraca. This group is characterized by a large, bivalved carapace that encloses the head and thorax. Their thoracic legs have a leaflike outer branch, and their abdomen has seven segments.12
The earliest recognized malacostracans in the fossil record are phyllocarids, with their origins dating back to the Early Cambrian period, over 500 million years ago. Most living phyllocarids are bottom-dwelling suspension feeders. The subclass includes extinct orders like Archaeostraca and Hoplostraca, as well as the extant order Leptostraca, which are also known as visored shrimp.32
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crustaceanAnnotated classificationSubclass PhyllocaridaEarly Cambrian to present.†Order ArchaeostracaDevonian to Triassic.†Order HoplostracaCarboniferous.Order LeptostracaPermian to present; bivalved carapace
Read MoreSubclass PhyllocaridaEarly Cambrian to present.†Order ArchaeostracaDevonian to Triassic.†Order HoplostracaCarboniferous.Order LeptostracaPermian to present; bivalved carapace
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malacostracanAnnotated classificationSubclass Phyllocarida Carapace large, appearing bivalved; thoracic legs with leaflike outer branch; abdomen 7-segmented, lacking uropods; anterior segments with pleopods (swimming legs). The earliest recognized malacostracans in the fossil record belong to this subclass. Most living representatives are bottom-dwelling suspension-feeders. About 20 species. †Order Archaeostraca
Read MoreSubclass Phyllocarida Carapace large, appearing bivalved; thoracic legs with leaflike outer branch; abdomen 7-segmented, lacking uropods; anterior segments with pleopods (swimming legs). The earliest recognized malacostracans in the fossil record belong to this subclass. Most living representatives are bottom-dwelling suspension-feeders. About 20 species. †Order Archaeostraca
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