Evidence of piscivorous diet in an enantiornithine bird from the Lower Cretaceous of Brazil

Cratoavis cearensis, described from a single specimen unearthed from the Crato Formation of the Araripe Basin in Brazil, represents one of the earliest known fossil avians from South America (ca. 117 My). We report on the presence of disarticulated fish elements associated with the skeleton and interpret them as contained within the digestive tract of this enantiornithine bird. These bony elements are similar to ribs of Dastilbe crandalli, a fish belonging to Gonorynchiforms. Dastilbe crandalli is abundant in the same Crato deposits that have yielded Cratoavis cearensis. The identified bony elements provide direct evidence of a piscivorous diet for this Brazilian enantiornithine, thus contributing to the meager evidence available for understanding the trophic specializations of this major clade of Mesozoic birds.