The Echinoid Directory

Gotlandechinus Regnell, 1956, p. 158

Diagnostic Features	Test shape unknown; plating thin and imbricate. Apical disc unknown. Ambulacra more or less straight and narrow; quadriserial. Inner series of plates small and excluded from adradial suture; outer series of plates larger and in contact with both perradial and adradial sutures. Outer series of plates with small adradial tubercle. Pore-pairs small, undifferentiated, forming a single vertical series close to the perradius in each half ambulacrum. Interambulacral zones wider than ambulacral zones; composed of 4 semiregular columns of polygonal plates. A few small secondary tubercles on interambulacral plates only. Peristome small, plating unknown. Lantern and spines unknown.
Distribution	Upper Silurian (Ludlow), Sweden (Gotland).
Name gender	masculine
Type	Gotlandechinus balticus Regnell, 1956, p. 160, by original designation.
Species Included	Only the type species.
Classification and/or Status	Stem group Echinoida; Echinocystitidae. Monotypic.
Remarks	In ambulacral structure Gotlandechinus resembles Echinocystites and Rhenechinus, except that its pore-pairs form a single perradial column in each half ambulacrum. Regnell, G. 1956. Silurian echinoids from Gotland. Arkiv fur Mineralogi och Geologi 2(7), 17-32, pl. 1.