FARINICHTHYS GIGAS, A NEW ALBULID FISH (TELEOSTEI: ELOPOMORPHA) FROM THE PALEOCENE OF THE PERNAMBUCO-PARAIBA BASIN, NORTHEASTERN BRAZIL
Valéria Gallo and Francisco J. De Figueiredo, Journal of Vertebrate Paleontology, 2002, 22(4):747–758
In Brazil, albuloid fishes have only been found in the Cretaceous of Chapada do Araripe, Northeastern Brazil, particularly in the Romualdo Member, Santana Formation. In this paper we describe Farinichthys gigas, gen. et sp. nov., a large albuloid fish from the Paleocene of the Maria Farinha Formation, Pernambuco-Paraiba Basin, based on a large skull, disarticulated suspensorium and isolated vertebrae. The fish is the most complete fossil vertebrate hitherto obtained from that formation and the oldest record of Albulidae in South America. It is preserved in a clay marl in association with bivalve and gastropod shells, brachyuran and echinoid carapaces, and insects, in addition to fish and reptile remains. Regarding other known albulids (e.g., Albula, Deltaichthys and Lebonichthys), the new genus differs mainly by the absence of contact between the epioccipital and the parietal bones, a very elongate ventral process of the quadrate, an oblique groove on the external surface of the hyomandibula, and a parietal branch of the supraorbital sensory canal directed towards the parietal without reaching it. The presence of an ossified interorbital septum, an elongate horizontal preopercular arm, and the ascending process of the subopercle reaching the articular facet for the hyomandibula define a clade formed by Farinichthys gigas plus Albula. It suggests an extension of the minimal age of this clade to the Paleocene (Danian).