Astragalus simplicifolius Nutt. ex Torr. & A. Gray

Homalobus lingulatus (Sheldon) Rydb. Bull. Torrey Club
40: 52. 1913.
Astragalus lingulatus Sheldon, Minn. Bot. Stud. 1: 118. 1894. Astragalus exilifolius A. Nels. Bull. Torrey Club 26: 10. 1899. Homalobus exilifolius Rydb. Bull. Torrey Club 40: 52. 1913.
An acaulescent perennial, with a deep-seated large root and a densely tufted cespitose caudex; leaves unifoliolate, densely crowded, blackening in drying; stipules scarious, free, 5 mm. long, pubescent; blade linear or narrowly linear-oblanceolate, pungently acute, involute, 2-4 cm. long, less than 2 mm. wide, silvery-canescent, tapering below into the filiform petiole; peduncles 1or 2-flowered, 2-3 cm. long; bracts small, scarious; calyx-tube campanulate, more or less strigose, 3-4 mm. long; lobes subulate, 1.5-2 mm. long; corolla 10-15 mm. (in the original description up to 20) long, ochroleucous or nearly white, the keel tipped with purple; petals similar to those of H. simplicif otitis; pod sessile, oblong, slightly curved, acuminate, purple-mottled, 12-15 mm. long, 4 mm. wide, somewhat turgid, few-seeded; seeds 2-5 mm. long, broadly obliquely oblong, with the funicle near one end.
Typr Locality: Foot of Big Horn Mountains, Wyoming. Distribution: Wyoming.

Homalobus simplicifolius (Nutt.) Rydb. Bull. Torrey Club
40: 52. 1913.
Phaca simplicifolia Nutt.; T. & G. Fl. N. Am. 1: 350. 1838. Astragalus simplicifolius A. Gray. Proc. Am. Acad. 6: 231. 1864. Tragacantha simplicifolia Kuntze. Rev. Gen. 948. 1891.
An acaulescent perennial, with a cespitose, densely tufted caudex; leaves densely crowded at the ends of its branches; stipules thin, membranous, pubescent, ovate, erose, 3-4 mm. long, free; leaves unifoliolate, 5-20 mm. long, 1-2 mm. wide, narrowly linear-oblanceolate, somewhat conduplicate or involute, silvery-canescent, acute; peduncles 3-10 mm. long, 1or 2-flowered; bracts subulate; calyx-tube campanulate, 2.5-3 mm. long, more or less pubescent, the teeth subulate, 1-1.5 mm. long; corolla ochroleucous; banner oblanceolate, with a broad claw; wings slightly shorter, the blade lunate, with an acute basal auricle, the claw slender, two-thirds as long as the blade; keel-petals 5 mm. long, the blade broadly lunate, rounded at the apex, and with a rounded basal auricle, the claw broad, nearly as long as the blade ; pod glabrous, according to the original description "somewhat triquetrous, longer than the calyx," obovate in crosssection.
Type locality: Rocky Mountains towards the sources of the Platte [Wyoming]. Distribution: Dry hills, southern Wyoming and Colorado.

Perennial, Herbs, Stems woody below, or from woody crown or caudex, Taproot present, Nodules present, Stems very short, acaulescent or subacaulescent, Stems prostrate, trailing, or mat forming, Stems less than 1 m tall, Stems solid, Stems or young twigs glabrous or sparsely glabrate, Stems or young twigs sparsely to densely hairy, Stems silvery, canescent, tomentose, cobwebby, or wooly, Stems with 2-branched hairs, dolabriform, Leaves alternate, Leaves petiolate, Stipules conspicuous, Stipules membranous or chartaceous, Stipules persistent, Stipules connate to each other, forming a tuber or sheath, Leaves simple, or appearing so, Leaves odd pinnate, Leaf or leaflet margins entire, Leaflets opposite, Leaves hairy on o ne or both surfaces, Leaves reduced to phyllodia, Flowers in axillary clusters or few-floweredracemes, 2-6 flowers, Inflorescences racemes, Inflorescence axillary, Bracts very small, absent or caducous, Flowers zygomorphic, Calyx 5-lobed, Calyx glabrous, Calyx hairy, Petals separate, Corolla papilionaceous, Petals clawed, Petals blue, lavander to purple, or violet, Banner petal narrow or oblanceolate, Wing petals narrow, oblanceolate to oblong, Wing tips obtuse or rounded, Keel petals auriculate, spurred, or gibbous, Keel tips obtuse or rounded, not beaked, Stamens 9-10, Stamens diadelphous, 9 united, 1 free, Filaments glabrous, Style terete, Style persistent in fruit, Fruit a legume, Fruit unilocular, Fruit tardily or weakly dehiscent, Fruit oblong or ellipsoidal, Fruit exserted from calyx, Fruit beaked, Fruit glabrous or glabrate, Fruit 11-many seeded, Seeds cordiform, mit-shaped, notched at one end, Seed surface smooth, Seeds olive, brown, or black.

Astragalus simplicifolius adalah spesies tumbuhan yang tergolong ke dalam famili Fabaceae. Spesies ini juga merupakan bagian dari ordo Fabales. Spesies Astragalus simplicifolius sendiri merupakan bagian dari genus Astragalus. Nama ilmiah dari spesies ini pertama kali diterbitkan oleh (Torr. & A.Gray) A.Gray.

Astragalus simplicifolius là một loài thực vật có hoa trong họ Đậu. Loài này được (Torr. & A.Gray) A.Gray miêu tả khoa học đầu tiên.