New Late Cretaceous (Cenomanian) fossil mayfly nymphs (Oligoneuriidae, Heptageniidae, Hexagenitidae) from the Redmond Formation, Labrador, Canada

• Published in: Canadian Journal of Earth Sciences
• Main Authors: Mueller, André S., Demers-Potvin, Alexandre V.
• Other Authors: Redpath Museum, McGill University, National Geographic Society Education Foundation, Fonds de recherche Nature et technologies Québec, Northern Scientific Training Program
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 2024
• Subjects: Newfoundland; Canada
• Online Access: http://dx.doi.org/10.1139/cjes-2023-0133; https://cdnsciencepub.com/doi/full-xml/10.1139/cjes-2023-0133; https://cdnsciencepub.com/doi/pdf/10.1139/cjes-2023-0133

Three new fossil mayfly (Ephemeroptera) larvae from the Redmond Formation (Cenomanian) of Newfoundland and Labrador, Canada, are described: Alatuscapillus icarus gen. et sp. nov. (family Oligoneuriidae), Cruscolli sheppardae gen. et sp. nov. (family Heptageniidae), and Protoligoneuria borealis sp. nov. (family Hexagenitidae). This discovery marks the first juvenile insect nymphs to be described from this formation and helps fill gaps in our understanding of the global and temporal distribution of mayflies during the Cretaceous period. Of these, C. sheppardae marks the oldest occurrence of the family Heptageniidae in the fossil record, while A. icarus and P. borealis mark the first fossil occurrences of the families Oligoneuriidae and Hexagenitidae in North America. The anatomy, preservation, and behaviour of these new mayfly species inferred from modern taxa consolidate the hypothesis that the Redmond Formation’s palaeoenvironment was lacustrine in nature.