On the occurrence of Gillicus arcuatus (Cope, 1875) (Pisces, Ichthyodectiformes†) in Mexico

Abstract

This work provides the description of the first specimen of the species Gillicus arcuatus (Cope, 1875) collected in Mexico. This ichthyodectiform fossil was collected in a marl flagstone quarry on Los Pilotes Ranch, Muzquiz County, Coahuila. The rocks of the quarry are of Turonian age, and constitute part of the Eagle Ford Formation. This Gillicus arcuatus specimen fits within the known temporal distribution of Gillicus, but extends the geographical distribution of this species to include Northern Mexico, where once the North American Western Interior Sea and the Western Tethys Sea converged. Los Pilotes Ranch is the southernmost fossil locality so far known where Gillicus has been found.Keywords: Gillicus, Ichthyodectiformes, Turonian, Eagle Ford Formation, Coahuila. (Cope, 1875) Resumen Se describe el primer ejemplar de la especie Gillicus arcuatus

A Late Cretaceous marine long snout “pejelagarto” fish (Lepisosteidae, Lepisosteini) from Múzquiz, Coahuila, northeastern Mexico

“…Alvarado-Ortega & Porras-Múzquiz, 2009, 2012Gonz alez-Barba & Espinosa-Ch avez, 2005;Porras-Múzquiz, Chatterjee, & Lehman, 2014;Riquelme, Alvarado-Ortega, Ruvalcaba-Sil, & Aguilar-Franco, 2013;among others). Overall, the geology of this area is known for the exposition of large sequences of laminated calcareous shales, intercalated with argillaceous limestones and chalky strata, which often contain small and large pyrite crystals.…”