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The Echinoid Directory

Family Pygorhitidae Lambert, 1909, p. 14

Diagnosis	Stem group atelostomates with: disjunct apical disc, the posterior oculars separated from the remainder of the disc by plates of interambulacra 1 and 4 meeting along the aboral midline ocular plates II and IV meeting behind the anterior genital plates so that the apical disc is elongate posterior oculars in direct contact with the margin of the periproct.
Range	Lower Jurassic (?Pliensbachian, Toarcian) to Lower Cretaceous (Valanginian); Europe, North Africa, India.
Remarks	A paraphyletic grade of forms basal to the Collyritidae and Disasteridae. Jesionek-Szymanska, W. 1961. Echinides irreguliers du Dogger de Pologne. Acta Geologica Polonica

Diagnosis

Stem group atelostomates with:

disjunct apical disc, the posterior oculars separated from the remainder of the disc by plates of interambulacra 1 and 4 meeting along the aboral midline
ocular plates II and IV meeting behind the anterior genital plates so that the apical disc is elongate
posterior oculars in direct contact with the margin of the periproct.

Range

Lower Jurassic (?Pliensbachian, Toarcian) to Lower Cretaceous (Valanginian); Europe, North Africa, India.

Remarks

A paraphyletic grade of forms basal to the Collyritidae and Disasteridae.

Jesionek-Szymanska, W. 1961. Echinides irreguliers du Dogger de Pologne. Acta Geologica Polonica

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