Astragalus magdalenae var. magdalenae

Herbage whitened with a lustrous, satiny vesture of hairs mostly up to 0.35-0.6 (0.65) mm. long; leaflets commonly small and crowded, 1.5-10 (15) mm. long; calyx 4.3-6.7 mm. long, the tube 3-4 mm., the teeth 1.3-2.7 mm. long; keel 7.4—9.6 mm. long; pod 1.5—2.6 cm. long, 1—1.3 cm. in diameter, the beak 2.5-8 mm. long.—Collections: 10 (o); representative: Mason 1954 (CAS, DS, NY, approximate topotypi), 1967 (CAS); Brandegee (from Santa Margarita Island) in 1889 (UC); Orcutt 29 (NY); Gentry 7361 (ARIZ, SD).

Coastal dunes and sandy flats behind barrier beaches, below 20 feet, apparently common locally along the Pacific Coast of Baja California from Scammons Lagoon on Sebastián Viscaino Bay to Magdalena Bay; on the Gulf Coast at San Francisquito Bay.—Map No. 117.—January to May, probably intermittently throughout the year.

Astragalus magdalenae (of Magdalenae Bay) Greene in Pittonia 1: 162. 1888 ("Magdalenae"), a substitute for A. candidissimus (Bth.) Wats., Bibl. Index 191. 1878, a later homonym of A. candidissimus Ledeb., 1831, based on Phaca candidissima (very white) Bth., Bot. Sulphur 13. 1844.—"Bay of Magdalena."—Holotypus, labeled "Magdalena, Barclay," BM!—Tragacantha californica (of Baja California) O. Kze., Rev. Gen. 940. 1891. A. Crotalariae var. magdalenae (Greene) Jones, Contrib. West. Bot. 10: 59. 1902.

The typical form of the satiny milk-vetch, var. magdalenae, is an attractive plant, recognized with ease by its almost silver-plated stems and foliage combined with sessile, bladdery fruits of moderate size, in these respects unlike any other sympatric coastal astragalus. The material is still too scanty to provide adequate contrasts between the flowers of var. magdalenae and var. niveus, but those of the latter appear to be a little larger and less brightly colored. On the Pacific Coast the stems of var. magdalenae are diffuse or trailing, but plants collected by Johnston at San Francisquito Bay on the Gulf side of the peninsula had "strictly ascending" stems (Proc. Calif. Acad. Sci. IV, 13: 1042), thereby simulating var. niveus in habit. This possibly distinct form has been referred to var. magdalenae because of its closely appressed, silvery vesture and high ovule-number (18). On the other hand, one collection (Gentry 7766, ARIZ, SD) from the Pacific Coast between San Hipolito and Asunción (lat. ± 21° N.) combines the decumbent growth-habit of var. magdalenae with the small, few-ovulate pod of var. niveus. The two varieties seem to be confluent and are, perhaps, not taxonomically separable.