The sea ray or guitarfish-like fossil pictured is an Iansan beurleni found in the Santana Formation of Brazil. It dates back 100 million years ago (Lower Cretaceous Period). This fossil might also be known by the name Rhinobatos beurleni (1968) as seen on the Henskens Fossils web site. Refer to 1996 paper on subject The new genus Iansan (Chondrichthyes, Rhinobatoidea) from the Early Cretaceous of Brazil and its phylogenetic relationships by Paulo M. Brito and Bernard Seret.
The fossil is part of the Cincinnati Museum Center collection (accession number VP7189). It was gift to the museum from Charles Fleischmann.
Fossil on display at Cincinnati Museum of Natural History & Science as of August 2013.