Guitarfish (Rhinobatidae) are a conservative group of extant rays with worldwide distribution and a fossil record that extends as far back as the Jurassic (Toarcian). Modern representatives of the family inhabit shallow tropical and sub-tropical waters, at depths less than 200 m, as well as some fresh water environments. Although complete specimens are known, the most abundant fossil remains are small, isolated teeth (less than 2 mm, measured mesiodistally). In North America, the earliest record of Rhinobatos sp. is from Lower Cretaceous (Lower Albian) of Texas. Rhinobatos sp. has been reported from Cretaceous rocks in other areas of the U.S. Western Interior including the Albian-Campanian of Texas, the Turonian and Santonian of Kansas, Cenomanian of Nebraska, Cenomanian and Turonian of New Mexico and South Dakota, and Coniacian of Saskatchewan, Canada. Recent discoveries of Rhinobatos incertus teeth from the Upper Albian to the Lower Campanian in the Cretaceous of Kansas document a reasonably continuous presence of the species in a variety of marine environments within the Western Interior Sea. New Kansas records of R. incertus teeth are from: McPherson County, Kiowa Shale (Upper Albian); Russell County, Dakota - Graneros Shale contact (Middle Cenomanian); Jewell County, Codell Sandstone (Middle Turonian), and; Trego County, Smoky Hill Chalk (Upper Coniacian) and Logan County, Smoky Hill Chalk (Lower Campanian).
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.
Vol. 110 • No. 3