Southwestern Ringstem (Anulocaulis leiosolenus), varieties howardii and lasianthus

Anulocaulis leiosolenus var. howardii

 

Overview and foliage, Guadalupe Mountains. Photographs by Wynn Anderson.

 

Flower buds and flowers. Photographs by Wynn Anderson.

• Common English Names: Howard's Ringstem
• Common Spanish Names: None known
• Scientific Name: Anulocaulis leiosolensis var. howardii (ann-noo-low-CALL-us lie-so-LEN-us var. HOW-ward-aye)
• Family: Nyctaginaceae (Four-O'clock Family)
• Geographic Range: A rare endemic plant, known only on gypsum rock outcrops on the west side of the Guadalupe Mountains in Otero Co. New Mexico.
• Description: Stout perennial herb rising from a gnarly woody rootstock with large, coarse, mostly smooth or with scattered pustulate (swollen base) hairs, glaucous blue-green to gray-green or dull green basal leaves, a few, largely leafless 3-5 foot long stems, loosely branching into open panicles terminated by scattered solitary or few flowered clusters of 1-inch long funnel shaped flowers, white, pale pink to rose pink in color often with darker rose to magenta exerted filaments. A nocturnal bloomer, the flowers opening at dusk and closing by mid-morning. In this variety, the leaves are usually pale grayish green, with sparse scattering of pustulate hairs, flower color is deep rose pink and the buds (tips) have minute hairs.
• Notes: One of four described varieties of this species. Ringstems are named for the often pronounced, viscid, sticky, sap-like ring that encircles the elongated stems between joints of the inflorescence of this and several other members of the plant family. The purpose of this feature is unknown but it often traps and holds small insects as well as dust and tiny particles of wind-blown debris and may well be a means of providing additional nutrients at flowering time.

Anulocaulis leiosolenus var. lasianthus

• Common English Names: Big Bend Ringstem
• Common Spanish Names: None known
• Scientific Name: Anulocaulis leiosolenus var. lasianthus (ann-noo-low-CALL-us lie-so-LEN-us var. lazy-ANN-thus)
• Family: Nyctaginaceae (Four-O'clock Family)
• Geographic Range: On shale and shale clays in southern Presidio and Brewster counties in Texas and immediately adjacent Chihuahua, Mexico.
• Description: Stout perennial herb rising from a gnarly woody rootstock with large, coarse, mostly smooth or with scattered pustulate (swollen base) hairs, glaucous blue-green to gray-green or dull green basal leaves, a few, largely leafless 3-5 foot long stems, loosely branching into open panicles terminated by scattered solitary or few flowered clusters of 1-inch long funnel shaped flowers, white, pale pink to rose pink in color often with darker rose to magenta exerted filaments. A nocturnal bloomer, the flowers opening at dusk and closing by mid-morning. In this variety, the leaves are dull green and densely covered with pustulate hairs, flower color is pink to pale pink, and the buds (tips) have minute hairs.
• Notes: One of four described varieties of this species. Ringstems are named for the often pronounced, viscid, sticky, sap-like ring that encircles the elongated stems between joints of the inflorescence of this and several other members of the plant family. The purpose of this feature is unknown, but it often traps and holds small insects as well as dust and tiny particles of wind-blown debris and may well be a means of providing additional nutrients at flowering time.

Last Update: 30 Sep 2013