Astragalus harbisonii Barneby,

Castillón, Eduardo Estrada, Quintanilla, José Ángel Villarreal, Delgado-Salinas, Alfonso & Rebman, Jon P., 2023, The genus Astragalus (Leguminosae: Papilionoideae: Galegeae) in Mexico, Phytotaxa 586 (1), pp. 1921-1935 : 1921-1935

36. Astragalus harbisonii Barneby, Leafl. W. Bot. 7: 34. 1953

Type:— MEXICO, Baja California, Punta Baja , 6 April 1950, C. F. Harbison s.n., (holotype: not seen; isotype: CAS0000953 digital image!, RSA0002909 digital image!) .

Perennial. Stems up to 30 cm long, diffuse o slightly ascending, densely villous, the trichomes up to 0.6 mm long, curly, mixed with longer and straight ones. Stipules 3–5 mm long, connate and clasping, the lowest ones, attached to 2 mm of its length, triangular, papery. Leaves 5–9 cm long, leaflets 13–23, 2.3–12 mm long, elliptic to orbicularelliptic, distally acute, rarely rounded. Peduncles 2.5–10 cm long, erect o curved; the racemes 1.4–5.9 cm long, flowers 12–23. Flowers whitish, sometimes bicolored, the petals (keel) lavender tinted, or the banner pale lavender, darker near center and the keel and the wings purplish-red; the calyx 5.1–6.6 × 2.7–3.2 mm, villous, with white and black mixed trichomes, the tube 3.5–4.2 mm long; the teeth 1.5–2.5 mm long, subulate; the banner 12–12.2 × 6.4–6.7 mm, rhombic to elliptic, briefly retuse distally; the wings 10.8–11.4 × 2.4–3 mm, the claw 4.4–4.8 mm long, the blade 7.5–7.9 mm long, oblong; the keel 9.2–9.9 × 2.5–2.7 mm, the claw 4.4–5 mm long, the blade 5.1–5.6 mm long, distally maculated. Pod 1.5–2 × 0.8–1.1 cm, sessile, ascending, elliptic, inflated, bladder-like, basally rounded or obtuse, distally contracted in a triangular beak, sutures very narrow, ventrally straight to scantily convex, dorsally convex, the valves thin, strigose, papery, membranous, ochre, something translucent, softly reticulate, septum absent; ovules 22–27; seeds 2.5 mm long, mitt-shaped, brown, sub-opaque.

Distribution:— Endemic to northwestern of Mexico. Distributed in a small area along the western coast of central Baja California (29°–57’N– 30°18’N), from Nueva Odisea, El Socorrito, Valle Tranquilo to Punta Baja) ( Fig. 10 ).

Habitat:— Coastal dunes; coastal cliffs; sandy soils; marine terraces; common in dune slacks and low beach dunes; arroyo bank; back edge of dunes; scrubland areas, 0.3–5 km away from the coasts; 5– 25 m.

Comments:— Sometimes forming dense mats about 3.5 m wide. In the areas where this species is found, at least other four species of Astragalus ( A. anemophilus , A. hornii , A. insularis and A. magdalenae ) can co-occur in the coastal dunes and adjacent areas, but only A. harbisonii and A. anemophilus have connate stipules, but A. anemophilus has longer (2.5–4 cm) pods.

Specimens examined:— BAJA CALIFORNIA: 1 June 1994, On coastal flats to the west of Mex. Rte. 1 between San Quintin and El Rosario; approx. 9 miles north of El Rosario , J. P. Rebman 2764 ( BCMEX, MEXU) ; 25 March 1985, Coastal bluffs, 15½ mi. north of El Rosario and ¼ mi. west of Hwy 1 at a prominent sand dune, A. C. Sanders 5432, E. Rodríguez, J. West et al. ( NY, TEX-LL) ; 19 April 1975, South side of Punta Baja near the tip, R. Moran 21769 ( CAS, ENCB, NY, TEX-LL, US) ; 5 July 1980, Bocana El Rosario , R. Moran 28964 ( NY, SD, TEX-LL) ; 28 February1985, From El Rosario to Punta Baja, D. E Breedlove 62217 ( CAS) ; 24 February1991, Near Punta Baja, D. E. Breedlove 71572 ( CAS) ; 14 June 1976, La Bocana de El Rosario , R. Moran 23531 ( CAS, NY, SD) ; 17 June 1980, Punta Baja, a small peninsula extending into the ocean from El Rosario , P. A. Bowler s.n. ( NY) ; 26 March 1973, La Bocana; El Rosario , A. Johnson 137, 138 ( SD) .

Figures

FIGURE 10. Map showing the distribution of Astragalus guatemalensis var. guatemalensis, A. guatemalensis var. brevidentatus, A. guatemalensis var. lozanii, A. harbisonii, and A. harshbergeri in Mexico.