Monographs Details: Astragalus kentrophyta var. ungulatus M.E.Jones
Authors:Rupert C. Barneby
Authority: Barneby, Rupert C. 1964. Atlas of North American Astragalus. Mem. New York Bot. Gard. 13(1): 1-596.
Family:Fabaceae
Synonyms:Astragalus montanus var. ungulatus (M.E.Jones) M.E.Jones, Kentrophyta ungulata (M.E.Jones) Rydb., Astragalus tegetarius var. ungulatus (M.E.Jones) Barneby
Description:Variety Description - Prostrate, forming densely woven mats or low-convex, at length rigid and prickly cushions 8-20 cm. in diameter, the longest internodes not over 1 cm. long, mostly shorter, the stems and leaves densely strigulose with appressed, and some narrowly ascending, nearly straight hairs up to 0.5-0.8 mm. long, cinereous or silvery; stipules 1.5-4 mm. long, the lowest in the year’s cycle connate into a shortly bidentate sheath, the upper ones with narrowly acuminate, ± acerose free blades; leaves 5-13 mm. long, 5 (or the lowest sometimes 3)-foliolate, the linear- elliptic leaflets 3-9 mm. long, the acerose spinule 0.9-1.5 mm. long; peduncles 1—4 mm. long, often concealed by stipules; calyx 3.6-4.7 mm. long, the tube 1.8—2.1 mm. long, 1.7—1.9 mm. in diameter, the teeth rigidly setaceous or narrowly subulate, 1.8—2.6 mm. long; petals whitish, the keel-tip purplish; banner 5.2—6.4 mm. long, 3.3—4.2 mm. wide; wings 4.9—5.8 mm. long, the claws 1.7-1.8 mm., the blades 3.7—4.5 mm. long, 1.4—1.8 mm. wide; keel 3.8—4.2 mm. long, the claws 1.7—1.9 mm., the blades 2.4—2.7 mm. long, 1.3—1.5 mm. wide; pod obliquely lance-acuminate in profile, 5—7.5 mm. long, 1.6—2 mm. wide near the obtuse base, thence gently narrowed upward and incurved into a slender, subulate beak surmounted by the persistent style; ovules 2-3 (4).

Distribution and Ecology - Calcareous gravel or gravelly clay knolls and gullied hillsides in the higher sagebrush valleys of northeastern and central Nevada, 5000-7200 feet (Elko, Eureka, Lander, and northern Nye Counties).—Map No. 38.—May to July.

Discussion:The talon kentrophyta, var. ungulatus, combines the matted growth-habit, silvery dolabriform vesture, and white flowers of var. Jessiae with the upwardly contracted, distinctly beaked pod of the much taller and coarser var. elatus. Its known stations are few and far apart, but the plants are locally plentiful, forming an element of the interesting pseudoalpine flora of knolls on the floor of the high valleys of central Nevada.
Distribution:Nevada United States of America North America|