Two undescribed species of the genus Squatina, caught by bottom-trawl during the OGMEX VIII, IX and PROBEMEX II oceanographic cruises were compared with S. dumeril Lesueur, 1818, the only well known species from the northern Gulf of Mexico. The collections were made off Tamaulipas, Veracruz and Tabasco. The descriptions of the new species refer to morphology, coloration pattern and dorsal fin shape and size. An English description of each species is included. Some specimens erroneously assigned to S. dumeril are deposited in Mexican collections. With these two new species, besides S. californica Ayres, 1859 and S. dumeril, the number of documented species of this genus in Mexico ascends to four, and a total of five are known from the western Atlantic. A key is provided for their identification.