Invertebrates
Metazoa Radiata
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Radiata

Animals with Radial Symmetry

Metazoa ├─Porifera (paraphyletic?) └─Radiata ├─Cnidaria └─Bilateria ├─Deuterostomia └─Protostomia ├─Ecdysozoa └─Lophotrochozoa
Introduction
Dendrogram
References

Polyorchis pencillatus - Red Eye Medusa
Phylum Cnidaria - Class Hydrozoa - Order Anthomedusae - Family Polyorchidae
image copyright © Keith Clements and Jon Gross Marine Life of the Northeast Pacific

Included here are invertebrates with radial symmetry: all longitudinal planes are equal around central body axis. They are also diploblastic (possessing only two germ layers, an ectoderm and endoderm, but, unlike the Bilateria, no mesoderm. Only two phyla belong here - the Cnidaria and Ctenophora

Radiata after Conway Morris, 1993

■──○Radiata ├?─Ctenophora └─○Cnidaria ├─┬─†Trilobozoa │ └─†Anabaritida └─┬─○Hydrozoa │ ├─Hydrozoa │ └─○Chondrophora │ ├─Porpitidae │ └─Velellidae └─┬─┬─†Fasciculida │ └─┬─Tentaculata │ └─Nuda └─┬─┬─┬─Scyphozoa (medusa, jellyfish) │ │ └─○Cubozoa │ │ └─○Cubomedusae │ │ ├─Carybdeidae │ │ └─Chirodropidae │ └─┬─†Conularida │ └─†Carinachitiida └─○?Anthozoa ├─†Xianguangiida ├?─Alcyonaria └─┬─Pennatulacea └─┬─†Echmatocriniida └─Anthozoa

References

Conway Morris, S., 1993

Fautin, DG & SL Romano 2000)

Hou & Bergström, 1997


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