Perforocycloides nathalieae new genus and species, an unusual Silurian cyclocystoid (Echinodermata) from Anticosti Island, Québec, Canada

Researchers have identified Perforocycloides nathalieae, a new genus and species of cyclocystoid, a rare and poorly understood class of echinoderms, from the early Silurian period on Anticosti Island in Québec, Canada. This discovery marks the first articulated cyclocystoid found in North America during this geological timeframe. The specimen is distinguished by its unique dorsal intermarginal sutural pores and canals, which suggest a novel communication system between the dorsal disc and ventral marginals/cupules. Comparative analysis indicates that Perforocycloides closely resembles Zygocycloides, hinting at greater Silurian diversity than previously thought. The study also highlights significant gaps in global knowledge of cyclocystoid distribution, particularly within Gondwana regions and Přidolí strata.

Ewin, T. A. M., Reich, M., Graham, M. R., & Cournoyer, M. E. (2019). Perforocycloides nathalieae new genus and species, an unusual Silurian cyclocystoid (Echinodermata) from Anticosti Island, Québec, Canada. PalZ, 93(4), 625–635. https://doi.org/10.1007/s12542-019-00483-w