Diagnostic Features
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- 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.
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Distribution
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Upper Silurian (Ludlow), Sweden (Gotland). |
Name gender |
masculine |
Type |
Gotlandechinus balticus Regnell, 1956, p. 160, by original designation. |
Species Included |
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Classification and/or Status |
Stem group Echinoida; Echinocystitidae.
Monotypic.
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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.
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