Systematic Paleontology Subclass: Ammonoidea Order: Ammonitida Family: Acanthoceratidae Genus: Graysonites Graysonites is an ammonite genus from the lower Cenomanian, upper Cretaceous named by Young, 1958. Its fossils have been fund in Texas. Graysonites adkinsi is the type. Graysonites is similar and closely related to Mantelliceras, in fact, for example, Manelliceras wacoensis is renamed Graysonites wacoensis