The Echinoid Directory

• Test very small (10 mm) and rounded in outline with thick margin.
• Apical disc central; gonopores possibly not yet open.
• Petals simple and straight; diverging towards ambitus; not well developed.
• Ambulacral and interambulacral zones of similar width at ambitus.
• Simple perradial furrows close to peristome.
• Peristome relatively large and circular.
• Periproct inframarginal.
• Oral plating not recorded.
• Internal partition arrangement not recorded.

Pliocene, California, USA.

Orchoporus koehleri Lambert & Thiery, 1914, by original designation.

• Only the type species.

Clypeasteroida; Scutellina; Scutelliformes; Scutellidea; Scutellidae.

Subjective junior synonym of Dendraster L. Agassiz, 1847.

Figured specimen has all the appearances of being a juvenile, and this taxon has generally been synonymized in the past with Merriamaster. The lack of food grooves and central disc are juvenile features.

J. W. Durham 1955. Classification of clypeasteroid echinoids. University of California Publications in Geological Sciences 31(4), 73-192.

Lambert, J. & Thiery, T. 1909-1925. Essai de Nomenclature Raisonnée des Echinides. L. Ferrière, Chaumont, fasc. 1: i-iii, 1-80, pls 1-2 (March 1909); fasc. 2: 81-160, pls 3-4 (July 1910); fasc. 3: 161-240, pls 5-6 (May 1911); fasc. 4: 241-320, pls 7-8 (March 1914); fasc. 5: 321-384, pl. 9 (Sept. 1921); fasc. 6-7: 385-512, pls 10-11, 14 (Dec. 1924); fasc. 7-8: 513-607, pls 12, 13, 15 (Feb. 1925).