30
1
March
105
116
BERG-MADSEN, V. 1987. A new cyclocystoid from the Lower Ordovician of Öland, Sweden. Palaeontology, 30, 1, 105–116.
Vivianne Berg-Madsen Monocycloides oelandicus gen. et sp. nov. is described from upper Arenig age beds on Oland, Sweden (Volkhov Stage, Langevoja Substage). The genus is monotypic and is the earliest known cyclocystoid echinoderm. Palaeogeographical origins of the cyclocystoids remain uncertain, but Monocycloides is regarded as a primitive sister group of the North American Ordovician Cyclocystoides. The Palaeontological Association (Free Access)