Polygala rimulicola var. mescalerorum (Mescalero milkwort)

Polygala rimulicola var. mescalerorum (Mescalero milkwort)

Photograph by Robert Sivinski (2004)
Scientific Name with Author
Polygala rimulicola Steyermark var. mescalerorum Wendt & Todsen
Common Name
Mescalero milkwort
Rare Plant Conservation Scorecard Summary
Overall Conservation Status Documented Threats Actions Needed

Small population size - inbreeding depression

Status surveys on abundance, distribution and threats. Population trend monitoring. Check seed set and viability for inbreeding depression

County Map
Mat-forming perennial herb from a woody base; stems numerous, glabrous, slender, mostly prostrate, branching, 1-5 cm long, green; leaves ovate-elliptic, 1.5-4 mm long, slightly fleshy; flowers 1 or 2, at the ends of branches, rose-purple and white; pedicels at maturity recurved and nodding, 2 mm long; wing petals broadly ovate, 4 mm long and 2.5 mm wide; keel petal 3 mm long, strongly beaked, greenish yellow; capsule broadly oval, 2 mm long, sparingly covered with short incurved hairs; seeds silvery pubescent, aril a glabrous knob on one end. Flowers June through September.
Similar Species
The prostrate, green, glabrous, nonglandular stems of Polygala rimulicola readily distinguish it from other New Mexican species in the genus. Its narrowly beaked keel petal separates it from P. rimulicola var. rimulicola.
New Mexico, Dona Ana County, San Andres Mountains.
Crevices in sandy limestone cliffs in montane scrub; 1,730-1,920 m (5,700-6,300 ft).
This variety is probably the rarest and most restricted plant taxon in New Mexico. It is presently known from only two small groups of plants on the north face of Black Mountain. Its total population is less than 200 individuals.
Conservation Considerations
The rugged, inaccessible nature of this plant's habitat protects it from any impacts of land use. Seed set and viability in this tiny population should be checked for inbreeding depression. The very small size of the population and its restricted habitat make the taxon susceptible to extinction.
Important Literature

*New Mexico Native Plants Protection Advisory Committee. 1984. A handbook of rare and endemic plants of New Mexico. University of New Mexico Press, Albuquerque.

Frazier, C.K. 1997. Field survey of the San Andres Mountains for Polygala rimulicola var. mescalerorum. Prepared for New Mexico Forestry Division, Santa Fe.

*Wendt, T. and T.K. Todsen. 1982. A new variety of Polygala rimulicola (Polygalaceae) from Doa Ana County, New Mexico. MadroƱo 29(1):19-21.

Information Compiled By
Robert Sivinski 1999

For distribution maps and more information, visit Natural Heritage New Mexico