A new species of Ivdelinia Andronov, 1961 from the Moroccan Givetian and its palaeoecological and palaeobiogeographical implications

The collection and study of benthic fauna from Middle Devonian carbonate buildups of the Ma der Basin in the eastern Anti-Atlas of Morocco permitted the taxonomic revision of previously described brachiopods from this area. Rhynchonellids dominate the brachiopod fauna. In this work, however, the focus is put on the description of a new gypidulid species, Ivdelinia pulchra, which belongs to the family Gypidulidae (subfamily Ivdelininae), found among the brachiopods from the Aferdou el Mrakib reef mound. It represents the youngest Ivdelinia species so far described and is compared with other ivdelinids. Ivdelinia pulchra occurs as densely packed communities which lived in a carbonate predominant environment during the earlier stage of reef mound growth, suggesting a more or less allochthonous state of these communities. However, this taxon does not properly belong to the reef guild. In addition we discuss the palaeoecology of the new species.