Upper Ordovician bryozoans of Morocco

The majority of Upper Ordovician bryozoan occurrences in Morocco are known from the Anti-Atlas. These faunas are abundant and diverse; however, many of them still remain unstudied. The few explored bryozoan faunas of the Katian age exhibit high abundance and diversity of erect branched and massive trepostomes accompanied by few esthonioporines, cryptostomes and fenestrates, whereas cystoporate bryozoans are not known here. They occupied various biotopes within inner- and outer-ramp settings. Bryozoan faunas from the Upper Ordovician of Morocco are rather related to faunas from other parts of the Mediterranean Province (France, Carnic Alps, Sardinia) containing few species of Laurentian and Baltic origin. Trepostome bryozoans from Moroccan occurrences often display signs of gigantism explained by undisturbed growth in cold and quiet environmental conditions.