Taxonomic revision of the New World genus Ariopsis Gill (Siluriformes: Ariidae), with description of two new species

The taxonomy of sea catfishes (Ariidae) has had a complex history. A recent checklist of catfish species recognized Ariidae as having by far the highest number of species with uncertain status among siluriform families. One of the main problems concerns the classification and species delimitation of the amphiamerican genus Ariopsis Gill. Some recent studies have listed Ariopsis under the synonymy of other genera (e.g., Sciades Muller & Troschel), while other systematic revisions recognize Ariopsis as valid but have pointed out the need for clarification of the species composition of the genus. Based on morphological and molecular evidence, the systematic status and taxonomic limits of the genus Ariopsis are herein redefined. Two new species of Ariopsis are described, one only known from the Archipielago de las Perlas, Pacific coast of Panama and another endemic to the Colombian Caribbean. Additionally, Ariopsis gilberti from the Pacific coast of Mexico and Ariopsis simonsi from Peru to Colombia (Eastern Pacific), previously listed as synonyms of Ariopsis seemanni, are herein resurrected. Finally, a molecular phylogeny is provided together with an identification key to the eight species in Ariopsis.