Gibbes, Proceedings of the Elliott Society of Natural History of Charleston, South Carolina 1: 273, 1859
What is Opuntia macrarthra?
Opuntia macrarthra is a small to medium-sized prickly pear cactus found along the coast of South Carolina and its islands.
The stems are prostrate or ascending; cladodes are narrowly oblong to obovate, 12-35 cm long, thick, pale green, and somewhat shining. Mostly there are no spines, but there may be one is some areoles up to 2.5 cm long. The leaves are subulate, 10 mm long, green, sometimes with purplish tips. The areoles are large, 2-3 cm apart, and filled with brown wool. Glochids are yellow.
Flowers are yellow. The fruit is narrowly obovoid, red, fleshy, and 4-6 cm long.
In 1919 Britton and Rose described Opuntia macrarthra as a long overlooked prickly pear. That is still the case today. At least one author has indicated it is synonymous with O. lata. Study is needed. See the original description.