Duration: Annual

Nativity: Native

Lifeform: Forb/Herb

General: Herbaceous annuals, very small to robust, stems clustered, prostrate to ascending, herbage glabrous or strigose.

Leaves: Alternate, irregularly pinnate with 3-7 obovate to rounded, alternate leaflets, 0.5-1.5 cm long, the terminal leaflet the largest, blade axis flat, stipules inconspicuous.

Flowers: Bright yellow, with banner, wing, and keel petals, corollas 3.5-5 mm long, the keel petal larger than the other petals, sepals 5, fused, calyx 2-2.5 mm long, lobes shorter that the tube with strigose surfaces, stamens 10 with 9 filaments fused and the uppermost 1 free, pistil 1, style 1, stigma 1, glabrous, ovary superior, generally 1-chambered, ovules 1-many, hypanthium 0 or flat to tubular, infloresences generally 2-4-flowered on peduncles 5-15 mm long, flowers bracted or not.

Fruits: Narrowly oblong legumes, ascending and exserted, 1.5-5 cm long, curved to flat, the fruit sometimes narrowed between the seeds with age, occasionally with small horn-like processes and hooked beaks 0.5-1.5 mm long, fruits dehiscent. Seeds 5-9 per legume.

Ecology: Found in deserts and mountains, to 6,000 ft (1829 m); flowering March-June.

Distribution: Arizona, California, Nevada; Mexico.

Notes: Look for this variety in Arizona in Mohave, Coconino, Yavapai, Gila, Maricopa, Pinal, La Paz, Yuma, and Pima counties, not in Santa Cruz or Chochise counties. Kearney and Peebles note that all Arizona specimens belong to var. brevivexillus with plants and flowers smaller than typical L. salsuginosus.

Ethnobotany: Specific uses for this species are unknown, but other species in the genus have uses.

Synonyms: Lotus salsuginosus var. brevivexillus

Editor: LCrumbacher2012

Etymology: Acmispon comes from the Greek acme for point or hook, while salsuginosus means growing in places overflowed by salt water, e.g. salt marshes, and brevivexillus is related to the root word vexillaris, "having a standard or banner, as in the large petal of a pea flower," thus with brevi- or "short" meaning short-bannered.