Eocrinoidea

Eocrinoidea Temporal range: Cambrian Stage 3–Silurian PreꞒ Ꞓ O S D C P T J K Pg N
Eocrinoid holdfasts (Middle Ordovician, Utah)
Colourful reconstruction of Gogia ojenai
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Echinodermata
Subphylum:	†Blastozoa
Class:	†Eocrinoidea Jaekel, 1899
Groups included[1]
†Ascocystitida †Ascocystitidae †Cambrocystidae[2] †Rhopalocystidae †Gogiida †Eocrinidae †Lyracystidae †Trachelocrinida †Heckerocrinidae †Trachelocrinidae †Cryptocrinitidae †Felbabkacystidae[3] †Lepidocystoidae[3] †Lichenoididae †Lingulocystidae †Palaeocystitidae †Rhipidocystidae †Ridersiidae
Cladistically included but traditionally excluded taxa
†Rhombifera[4] †Diploporita[4] †Paracrinoidea[4] †Parablastoidea[citation needed] †Blastoidea[4] †Coronoidea[5] Crinoidea ?[6]

The Eocrinoidea were an extinct class of echinoderms that lived between the Early Cambrian and Late Silurian periods. They are the earliest known group of stalked, brachiole-bearing echinoderms, and were the most common echinoderms during the Cambrian.

The earliest genera had a short holdfast and irregularly structured plates. Later forms had a fully developed stalk with regular rows of plates. They were benthic suspension feeders, with five ambulacra on the upper surface, surrounding the mouth and extending into a number of narrow arms.^[7][8]