Thursday, May 2, 2024

[PaleoIchthyology • 2024] Afrocascudo saharaensis • A Saharan Fossil and the Dawn of Neotropical Armoured Catfishes in Gondwana


Afrocascudo saharaensis
Brito, Dutheil, Gueriau, Keith, Carnevale, Britto, Meunier, Khalloufi, King, de Amorim & Costa, 2024

  
Highlights: 
• We describe a Cretaceous endemic Neotropical freshwater catfish from Morocco.
• Overlooked evolutionary events took place at the outset of the break-up of Gondwana.
• Iconic Neotropical freshwater lineages diversified after surviving the K/Pg extinction.

Abstract
Siluriformes are considered as primarily freshwater and have frequently been a model for the study of historical biogeography. Among catfishes, the most diverse clade is the Loricarioidei, a Neotropical group for which the fossil record extends back to the Palaeocene of Argentina. Here we describe a fossil from the early Late Cretaceous of Morocco, exhibiting typical morphological traits of the Loricariidae. A phylogenetic analysis integrating morphological characters with a multigene database for the main loricarioid lineages and outgroups highly supports inclusion of the fossil within the Loricariidae. A time-calibrated analysis corroborates the origin of loricarioids at about 112 MYA. The presence of this loricariid in Africa provides evidence that loricarioids have diversified before the separation of Africa and South America. The Moroccan loricariid shows an ancient evolutionary history that, in Africa, ended in the Late Cretaceous but persisted in South America, later surviving the K/Pg extinction.


 
Afrocascudo saharaensis gen. et sp. nov.

 
Paulo M. Brito, Didier B. Dutheil, Pierre Gueriau, Philippe Keith, Giorgio Carnevale, Marcelo Britto, François J. Meunier, Bouziane Khalloufi, Andrew King, Pedro F. de Amorim and Wilson J.E.M. Costa. 2024. A Saharan Fossil and the Dawn of Neotropical Armoured Catfishes in Gondwana. Gondwana Research. In Press. DOI: 10.1016/j.gr.2024.04.008