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Afrocascudo is a controversial genus of extinct Neopterygii fish, either an ancient loricariid catfish or a juvenile Obaichthyidae Lepisosteiformes of the genus Obaichthys. It is known from the Late Cretaceous Douira Formation (Kem Kem Group) of Morocco. The genus contains a Monotypic taxon, A. saharaensis, known from a partial articulated specimen.
In 2024, Brito et al. described Afrocascudo saharaensis as a new genus and species of loricariid catfishes based on these fossil remains. The Genus, Afrocascudo, combines the Latin word "Afro", meaning "Africa", with the Portuguese "cascudo", the common name used in Brazil for certain armoured catfishes. The specific name, saharaensis, references the Sahara Desert of North Africa, from which the holotype was discovered.
The describers of Afrocascudo suggested that this fossil represents the oldest known catfish and, as such, the oldest known loricarioid. Before its description, the Argentinian Corydoras revelatus was the oldest known loricarioid, from the Late Paleocene (~58.5 Ma). The presence of a crown group loricarioid catfish in the Late Cretaceous would indicate that the clade had already significantly diversified much earlier than was previously thought. This hypothesis has been disputed by other researchers who posit that the remains do not belong to a catfish.
However, in the same year, Britz et al. considered this taxonomic placement fallacious, and reinterpreted Afrocascudo as a juvenile Obaichthyidae Lepisosteiformes, most likely an immature individual of the contemporary Obaichthys. They noted significant morphological differences between this taxon and true loriicarids, and observed that the identified traits are more similar to those of Obaichthys. Britz et al. discussed their skepticism based on the erroneous phylogenetic data matrix and reconstruction of the taxon from the previous study by Brito et al., the latter of which does not closely match the fossilized remains. They also pointed out that Brito et al. only provided the arguments in favor of their conclusion without an extensive discussion, and that their hypotheses would all be considered doubtful if Afrocascudo is considered a non-teleost fish. As such, they argued that Afrocascudo should be considered a junior synonym of Obaichthys.
Shortly after the comment by Britz, Brito et al. published a rebuttal paper, acknowledging that their reconstruction took artistic liberties, proposing a possible in-life appearance for the species. They further admitted to small errors in the original study, specifically in the phylogenetic matrix and one of the figures from the supplementary data. They also concurred with Britz et al. that features of the caudal endoskeleton are not easily distinguishable. Still, they criticized Britz et al. for proposing a taxonomic status change of Afrocascudo on the basis of simple comparisons without testing hypothesis (i.e. reproducing 3D renderings), and considered the interpretation of the taxon as a juvenile Lepisosteiformes or a Holostei unlikely. In their rebuttal, Brito et al. further claimed that Afrocascudo could not be a juvenile since the type specimen is completely ossified, an indicator for maturity. They also noted the absence of important holostean characters including the canalicules found in gar scales and the presence of teleost fish traits, such as the structure of the caudal fin, histological features, and the dorsal and lateral surfaces which are covered with bony plates and odontodes. Additionally, all principal rays of the median fins in lepisosteiforms are segmented and branched, which is different from the dorsal fin of Afrocascudo. Thus, they stood by their original conclusion that Afrocascudo represents the oldest known catfish.
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