On the status of the species of Acanthistius (Gill, 1862) (Percoidei) in the South-West Atlantic Ocean

Abstract

We review the species of Acanthistius Gill (1862) (Osteichthyes, Percoidei) from the South-Western Atlantic, solving a discrepancy concerning the taxonomic status of Acanthistius brasilianus (Cuvier & Valenciennes 1828) and Acanthistius patachonicus (Jenyns 1842), and providing an objective diagnostic key for the two species. While Argentinean fishery biologists consider A. patachonicus to be a synonym of A. brasilianus, ichthyologists elsewhere regard them as separate species with different distributional ranges. Based on a literature review, examination of museum specimens and observation of live individuals in the field, we identified the sources of the dissent and concluded that A. brasilianus and A.patachonicus are separate species, differing in diagnostic morphological characters and distinctive color patterns and having slightly overlapping distributional ranges. Distinction between these two species has significant implications for management and conservation.