Opuntia macrarthra, Eastern Beach Pricklypear

Gibbes, Proceedings of the Elliott Society of Natural History of Charleston, South Carolina 1: 273, 1859

Neotype (O. macrarthra); Isoneotype (O. macrarthra); Herbarium (possible); Herbarium; (possible); Painting; Painting (Britton and Rose, The Cactaceae, v1 1919, Plate XV and Plate XXII)

Original Description

What is Opuntia macrarthra?

Opuntia macrarthra is a small to medium-sized pricklypear cactus found on the coastal plains west of South Carolina and its islands. 

Details

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 in 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 pricklypear. That is still the case today. At least one author has indicated it is synonymous with O. lata. See the original description.

For more information, see:

Morphological and Ecological Characterization of Opuntia Miller on the Coast of South Carolina, 2016, Holmes K.