Phylum: Echinodermata

Class: Echinoidea - Echinoids
(regular echinoids)

Pennsylvanian Period (click for Cretaceous Period)
Archaeocidaris sp. echinoid plates Formation: Graham (Finis shale) Period:  Pennsylvanian  (c. 300 mya) Loc:  Young Co., TX.  2 Feb 2020.	Archaeocidaris sp. echinoid plates Formation: Graham (Finis shale) Period:  Pennsylvanian  (c. 300 mya) Loc:  Young Co., TX.  2 Feb 2020.
Archaeocidaris sp. echinoid plates Formation: Mineral Wells (Salesville shale) Period:  Pennsylvanian  (c. 300 mya) Loc:  Palo Pinto co., Tx.  Jan. 27, 2007.	Archaeocidaris sp. echinoid spines Formation: Mineral Wells (Salesville shale) Period:  Pennsylvanian  (c. 300 mya) Loc:  Palo Pinto co., Tx.  Jan. 27, 2007.
Echinoid spines Formation:  Period:  Pennsylvanian  (c. 300 mya) Loc:  2006.	Echinoid spines and plates Formation:  Period:  Pennsylvanian  (c. 300 mya) Loc:  Wise co., Tx.  Jan. 27, 2007.