Asterocidaris

Asterocidaris is a genus of fossils sea urchins in the family Hemicidaridae. These epifaunal grazer-deposit feeders lived in the Middle and Upper Jurassic age (from 171.6 to 161.2 Ma).^[2]

Asterocidaris Temporal range: Jurassic PreꞒ Ꞓ O S D C P T J K Pg N
Fossil of Asterocidaris species from Morocco
Fossil spicules of Asterocidaris meandrina
Scientific classification
Kingdom:	Animalia
Phylum:	Echinodermata
Class:	Echinoidea
Infraclass:	Carinacea
Family:	†Hemicidaridae
Genus:	†Asterocidaris Cotteau, 1859[1]

Species

• Asterocidaris besairiei Lambert, 1936 †
• Asterocidaris meandrina (Agassiz 1840) † ^[3]
• Asterocidaris ragoti Lambert, 1936 †

^[4]

Description

These fossil spined echinoid sea urchins can reach a diameter of about 25 millimetres (0.98 in), with spicules of about 69x60mm.^[5] They are hemispherical, flattened beneath, with small apical disc.^[6]

Distribution

Fossils of species within this genus have been found in the Middle to Upper Jurassic sediments (Bajocian-Oxfordian) in Europe, Madagascar and Africa (Morocco).^[4][6]