Details

Autor(en) / Beteiligte

• Congreve, Curtis R.
• Krug, Andrew Z.
• Patzkowsky, Mark E.
• Sevastopulo, George

Titel

Phylogenetic revision of the S trophomenida, a diverse and ecologically important P alaeozoic brachiopod order

Ist Teil von

• Palaeontology, 2015-07, Vol.58 (4), p.743-758

Erscheinungsjahr

2015

Link zum Volltext

Quelle

Wiley Online Library

Beschreibungen/Notizen

• Abstract The order S trophomenida was an ecologically abundant and taxonomically diverse group of P alaeozoic brachiopods that originated in the earliest O rdovician and went extinct in the C arboniferous. During their long geological range, the S trophomenida survived two of the ‘ B ig F ive’ mass extinction events, the L ate O rdovician and the L ate D evonian, 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 P lectambonitoidea (plectambonitoids). Despite being treated as separate clades, the plectambonitoids may form a paraphyletic grade into the strophomenoids. We present a detailed higher‐level parsimony‐based phylogenetic analysis of the S trophomenida, consisting of 69 characters and 62 exemplar species sampled from the majority of the taxonomically defined families/subfamilies. Several species of basal chonetids (strophochonetids) were also included in this analysis, as they may be closely related to the S trophomenida and share several characters with both the plectambonitoids and strophomenoids. The phylogenetic analysis suggests the plectambonitoids, as originally defined, are paraphyletic to the monophyletic strophomenoids. The basal chonetids are reconstructed as a monophyletic group that is sister to the strophomenoids, suggesting that their proper placement might be within the S trophomenida. The topology also suggests that at least 17 of the taxonomically defined strophomenoid and plectambonitoid families are likely to be monophyletic. The P lectambonitidae and the T affiidae as defined are paraphyletic, and the G rorudiidae and L eptostrophiidae are polyphyletic. Furthermore, subfamilies L eptodontellinae, D icoelostrophiinae, P alaeostrophomeninae and A egiromeninae are raised to the level of family. When analysed within this phylogenetic context, the L ate O rdovician mass extinction event had little effect on the large‐scale evolution of the group.