Griffiths, Bulletin of the Torrey Botanical Club 43(2): 92, 1916
Holotype; Isotype NOTE: the holotype specimen is notable because it contains two different cladode types. Only the cladode on the left conforms with the original description and plants found near the type locality. Also, the cladode on the left agrees with the isotype specimen. Therefore, we accept the pad on the left as the correct holotype. The pad on the right is unidentified but may be O. magenta, a more southern plant.
Opuntia anahuacensis is a plant of sandy soils associated with the Gulf of Mexico. The plants are a foot or two tall, but they form large horizontal thickets up to 6(8)-ft across. Groupings of plants can form impenetrable masses many feet across. The cladodes are about 5-inches wide and up to 11- or 12-inches long; they are obovate with suggestions of a neck. Pads can have multiple spines or essentially no spines. But, there is usually no more than 1-2 major spines per areole. One spine is porrect; if there is a second spine, it is deflexed. The flower buds are generally long and tapered. The stigma is white. Fruit is pyriform, up to 2- or 3-inches long and sometimes deeply pitted. See the original citation. O. anahuacensis is hexaploid.
O. anahuacensis co-occurs with O. bentonii, but that latter species is decidedly more spiny and has yellow stigmas. Plants have been found in sandy areas on Galveston Island, Texas and several locations on Bolivar Peninsula, Texas. An anecdotal report places the species in southwestern Louisiana. Additionally, isolated populations have been found in sandy soils as much as 45-miles inland growing in deep, sandy soils along waterways. O. anahuacensis may occur along the many secluded miles of the Texas Gulf Coast. O. anahuacensis is not commonly noticed as a distinct taxon, and it seems unrecognized by many Texas botanists. O. anahuacensis may have been mistaken for O. stricta, which was reported along the upper Texas Gulf Coast, but the two plants are different.