Phylogenetic revision of the Strophomenida, a diverse and ecologically important palaeozoic brachiopod order

The order Strophomenida was an ecologically abundant and taxonomically diverse group of Palaeozoic brachiopods that originated in the earliest Ordovician and went extinct in the Carboniferous. During their long geological range, the Strophomenida survived two of the ‘Big Five’ mass extinction events, the Late Ordovician and the Late Devonian, suggesting that they are potentially informative taxa for studying the evolutionary effects of these two distinct mass extinctions, each with drastically different forcing mechanisms. However, while there have been previous phylogenetic studies on smaller groups within the Strophomenida, the phylogenetic relationships of the whole group are still largely unknown. The group has been divided into two major superfamilies, the Strophomenoidea (strophomenoids) and the Plectambonitoidea (plectambonitoids). Despite being treated as separate clades, the plectambonitoids may form a paraphyletic grade into the strophomenoids. We present a detailed higher-lev...