Devonian stromatoporoid historical collections in the Natural History Museum, London (UK): redescription, taxonomic revision and implications for stromatoporoid global paleobiogeography

Devonian stromatoporoid collections in the Natural History Museum, London (UK) have been deposited for over 100 years. The characteristics and systematic position of these specimens, however, have received little attention. In this study, a total of 307 Devonian stromatoporoid specimens comprising material documented by Nicholson (1886-1892) from the UK, Germany, United States, and Canada, plus specimens described by Ripper (1933, 1937a, b, c) from Australia, were re-examined. Overall, 50 species belonging to 29 genera were systematically redescribed based on recent progress, mainly including Actinostroma, Petridiostroma, Stictostroma, Pseudotrupetostroma, Parallelopora. Three-dimensional reconstructions of the type genus are illustrated following the earlier works of Stearn (1966) and Cockbain (1984). The reconstructed skeletons reveal stromatoporoid architectural patterns, crucial for enhancing understanding and revision of stromatoporoid identification. This study underscores the significance of three-dimensional reconstruction in taxonomic research on stromatoporoid. The NHMUK material is combined with data from publications and the Paleobiology Database (PBDB) to perform a network analysis of the global occurrence of Devonian stromatoporoids at the generic level; this reveals a close relationship of global stromatoporoid fauna during the Early Devonian, indicating a widespread distribution, despite this interval being regarded as a time of global stromatoporoid contraction. The Middle Devonian assemblage shows a much higher cosmopolitan occurrence in the context of the subsequent Eifelian-Givetian global stromatoporoid proliferation, consistent with the known pattern from other studies of Middle Devonian stromatoporoids. Overall, the NHMUK collections are a valuable resource to help understand the global occurrence of Devonian stromatoporoids.