The Echinoid Directory
Thierychinus delaunayi Lambert, in Lambert & Thiery, 1914; Museum National d'Histoire Naturelle, Paris J00789 (holotype). Bajocian, Middle Jurassic, Saint-Gaultier, Indre, France. One column of ambulacral plates a little above the ambitus (note inner series of small pore-pairs)
Diameter of test 33 mm.