The Echinoid Directory

Stem group Stem group atelostomates (disasteroids)

[=Disasteroida of Mintz, 1968, p. 1287]

Diagnosis

 Irregular echinoids with:

  • elongate, usually disjunct apical disc, the posterior oculars separated from the remainder of the disc and plates of interambulacra 1 and 4 meeting along the aboral midline
  • plastron plating protosternous.
Range
Lower Jurassic (?Pleinsbachian, Toarcian) to Lower Cretaceous (Albian); Europe, North Africa, India.