Sharpkeel Milkvetch

Hamosa acutirostris (S. Wats) Rydb. Bull. Torrey Club 54:331. 1927.
Astragalus acutirostris S. Wats. Proc. Am. Acad. 20: 360. 1885. Astragalus slreptopus Greene, Bull. Calif. Acad. 1: 155. 1885. Oxytropis acutirostris M. E. Jones, Proc. Calif. Acad. II. 5: 677. 1895. Aragallus acutirostris A. Heller, Cat. N. Am. PI. 4. 1898
An annual; stem 0.5-3 dm. long, branched at the base, terete, decumbent, strigose; leaves 2-3 cm. long, ascending; stipules ovate or lanceolate, 1-2 mm. long; leaflets 9-15, oblong to obovate, retuse at the apex, cuneate at the base, pubescent beneath with somewhat kinked hairs, 5-8 mm. long, thickish; peduncles 4-8 cm. long; racemes 2-4 cm. long, 3-5-flowered; bracts lanceolate, 1 mm. long; pedicels very short; calyx more or less black-hairy, the tube 1.5 mm. long, the teeth subulate, of about the same length; corolla whitish or purple-tipped, 4-5 mm. long; banner obovate; wings slightly shorter, the blades obovate; keel-petals about as long, broadly lunate, acuminate, the tip erect; pod slightly arcuate, 1.5-2 cm. long, 3 mm. wide, minutely strigose, reticulate, acute at each end, sulcate on the lower suture, cordate in cross-section.
Type locality: Brown's Rranch, Mohave Desert. Distribution: Mohave Desert. California.

Annual, Herbs, Taproot present, Nodules present, Stems very short, acaulescent or subacaulescent, Stems erect or ascending, Stems or branches arching, spreading or decumbent, Stems prostrate, trailing, or mat forming, Stems less than 1 m tall, Stems solid, Stems or young twigs sparsely to densely hairy, Stem hairs hispid to villous, Leaves alternate, Leaves petiolate, Stipules conspicuous, Stipules membranous or chartaceous, Stipules persistent, Stipules free, Leaves compound, Leaves odd pinnate, Leaf or leaflet margins entire, Leaflets opposite, Leaflets 5-9, Leaflets 10-many, Leaves hairy on one or both surfaces, Flowers in axillary clusters or few-floweredracemes, 2-6 flowers, Inflorescences racemes, Inflorescence axillary, Inflorescence or flowers lax, declined or pendulous, Bracts very small, absent or caducous, Flowers zygomorphic, Calyx 5-lobed, Calyx glabrous, Petals separate, Corolla papilionaceous, Petals clawed, Petals white, Petals blue, lavander to purple, or violet, Petals bicolored or with red, purple or yellow streaks or spots, Banner petal narrow or oblanceolate, Wing petals narrow, oblanceolate to oblong, Wing tips obtuse or rounded, Keel petals auriculate, spurred, or gibbous, Stamens 9-10, Stamens diadelphous, 9 united, 1 free, Filaments glabrous, Style terete, Style persistent in fruit, Fruit a legume, Fruit stipitate, Fruit tardily or wea kly 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 acutirostris is a species of milkvetch known by the common name sharpkeel milkvetch. It is native to the Mojave Desert and surroundings of California, Nevada, and Arizona, where it grows in dry, sandy, gravelly areas.