Gondwana breakup under the ephemeral look
Felipe Donateli Gatti, Frederico Falcão Salles, P. J. Suter, Yuri Luiz Reis Leite
Abstract
Atalophlebiinae (Ephemeroptera, Leptophlebiidae) is a mayfly subfamily present in temperate and mountainous areas of South America and Australia. We tested the hypothesis that both vicariance and dispersal related to the second phase of Gondwana breakup—which began in the Early Cretaceous and resulted in the separation between Madagascar and India from Antarctica and Australia—contributed to the origin, diversification, and shaped the current distribution of this group. The hypothesis was tested using Bayesian phylogenetic trees, fossil-based molecular dating, and ancestral range estimation to reconstruct the biogeography of the lineages within this group. The results suggested an origin in the late Gondwana supercontinent for Atalophlebiinae (85.76–136.63 mya) after a vicariant event during the Cretaceous period. Subsequently, the lineage diversified into a scenario that refers to a Gondwanic corridor formed by South America, Antarctica, and Australia. At the end of the separation of the continents that made up the Gondwanic corridor, speciation occurred within the current distribution areas. The diversity and current distribution of Atalophlebiinae were shaped by complex processes of vicariance, dispersal, and speciation within the Gondwanic corridor during the second phase of the supercontinent breakup. Mayflies have difficulty in crossing transoceanic barriers, which suggests that most living taxa are the result of more recent local ecological and historical processes.