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Diadematacia

Diadematacia
Temporal range: Late Triassic–Recent
Echinothrix diadema.JPG
Echinothrix diadema
Scientific classification
Kingdom: Animalia
Phylum: Echinodermata
Class: Echinoidea
Subclass: Euechinoidea
Superorder: Diadematacia
Orders

Diadematoida
Echinothurioida
Pedinoida


Diadematoida
Echinothurioida
Pedinoida

The Diadematacia form a superorder of sea urchins. Unlike most other sea urchins, they generally have hollow spines. The tubercles on their tests are perforated, and most species possess gills.



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Wikipedia

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