– Coryphantha ramillosa (2009)

By Joe Merkelbach (October 2009)

Since HSCSS will be presenting our donation to the endowment fund for Coryphantha ramillosa Cutak at the October meeting, I think some details about the species are justified.

The whiskerbush, bunched or Big Bend cory cactus is endemic to limestone areas of the Chihuahuan scrub desert of northern Mexico and far west Texas. It is found on limestone outcrops of the canyon edges and hilltops of the rough country in the vicinity of Big Bend National Park. Recent discovery work has found some new locations on private ranch land east of the park within the U.S. The cactus is in the threatened category of the United States threatened and endangered species list, designated in 1979.

The species was first recognized and collected for botanical study by A. R. Davis, in 1936 and described and named by Ladislaus Cutak, founder of HSCS, in 1942. The holotype specimen, the study plant used for describing the species, is in the herbarium library of Missouri Botanical Garden.

C. ramillosa is multiheaded, with stems about 3 inches in diameter sometimes forming mounds in habitat. The groove running the length of the upper surface of the prominent tubercles is the trait that signifies the Coryphantha genus. These grooves are known to produce nectar that attracts likely pollinators for other coryphanthas.

The four dark central spines are surrounded by up to 25 lighter-colored ones, all located at the apex of each tubercle. The flowers range in color from light pink to deep rose, indicating a relationship to mammillarias. The fruits, though, are green and juicy rather than pink.

The species is threatened due to its affinity for a very specific arid, rapidly draining limestone habitat. The required habitat is rather small in area, a negative, and inaccessible, a positive. This proclivity for rare habitat is the usual reason for endangered status for plants and animals.

The Desert Botanical Garden in Phoenix has charge of the protection of C. ramillosa under the national Center for Plant Conservation program. Our donation will initiate the endowment fund to maintain this cactus, which seems very appropriate considering our group’s tie to Lad Cutak.

More Information and Images:
U.S. Department of Agriculture Plants Database – http://plants.usda.gov/java/profile?symbol=CORA7
Efloras.org Flora of North America – http://www.efloras.org/florataxon.aspx?flora_id=1&taxon_id=242415318
Texas Parks and Wildlife Listed Plants – https://www.tpwd.state.tx.us/huntwild/wild/species/bunchcc/