Description of two new species of the brachyuran genus Xanthosia Bell, 1863, from the upper Albian to Cenomanian Weno and Pawpaw formations from Tarrant County, Texas, increases the number of species in the genus to fifteen. Xanthosia has been recognized in England, the Netherlands, Madagascar, and in in the states of New Jersey, South Dakota, and Texas. The geologically oldest species from England gave rise to species from North America, Europe, and Madagascar. One group of species, with representatives from South Dakota, New Jersey, and Madagascar, may represent a separate taxon. The species “Xanthosia” robertsi Secretan is herein removed from the genus and placed within the Portunidae, not the Xanthidae.