Astragalus sagitticarpus A.E. Estrada, Villarreal & Encina,

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

85. Astragalus sagitticarpus A.E. Estrada, Villarreal & Encina, Phytotaxa 166–167. 2020

Type:— MEXICO, Morelos, Municipio Huitzilac, km 74 carretera (antigua) México-Cuernavaca , elev. 2300 m, 10 Nov 1978, O. Téllez 526 (Holotype MEXU 1219252 !) .

Annual herb, caulescent. Stems suberect, curved, weak, up to 30 cm long, subglabrate or with scatered, trichomes 0.2-0.3 mm long, appressed to sub-appressed. Stipules free, 3–10 × 1–1.3 mm, straight or basally oblique, triangular to triangular-lanceolate. Leaves few, at least 3–8 leaves per stem, so the stems obvious and conspicuous, not hidden by foliage, 3.6–6.5 cm long, leaflets 15–19, 2–6.5 × 1–2.9 mm, elliptic, obovate-elliptic, oblong-elliptic, distally rounded or ending in a minute mucro, basally rounded or gradually narrowed, bicolored, light-green and pilose or scattered pilose, the trichomes 2.5–5 mm long, straight, more densely so in young leaves, sometimes the trichomes more densely so along the midvein and edges adaxially, dark-green, glabrous or rarely with very few scattered, straight, white trichomes. Peduncles weak, thin, 1.7–7.2 cm long, straight or curved, ascending, pubsecent as the stems; the racemes 0.2–1 cm long, 2–7 flowered, its trichomes 0.2–0.3 mm long, straight, adpressed to sub-adpressed, white and black. Flowers blue, turning purple, purple or white with age, at least on the keel tip, up to 8 mm long, ascending and remaining so until open or belatedly semi deflexed but no completely pendulous; the calyx 2.4–3 × 1.5–1.9 mm, the tube 2.2–2.5 mm long, narrow to wide campanulate, inequilaterous, somewhat gibbous dorsally at base, always densely strigulose with black, straight trichomes, very rarely with some few, appreseed to sub-adpressed, white, sparsed trichomes present, the teeth 0.3–0.5 mm long, triangular, sometimes (0.57 mm wide) wider than long, always densely strigulose with black trichomes, thence, the teeth almost with black colored, and strongly contrasting with the less black colored tube; the banner 8.2–8.6 × 4.3–4.5 mm, sessile, elliptic, elliptic-ovate to obovate, apically rounded to truncate-rounded, narrowing gradually to the base, curved; the wings 6.7–7 × 2.5–2.9 mm, the claw 2.9–3.1, the blade 4–4.1 mm long, oblong, oblique and rounded distally; the keel 6–6.5 × 1.3–1.5 mm, the claw 2.9–3 mm long, the blade 3.5–3.6 mm long, half-obovate, incurved, apically rounded but distally triangular-rounded; ovules 6. Pod pendulous, stipitate, stipe 2.2–2.5 mm long, persistent on the receptacle, the body 6–7 × 4–4.5 × 0.6–0.8 mm, elliptic, oblong-elliptic to ovate-elliptic, straight, dorsoventrally compressed, basally gradually narrowing, ending in the stipe, gradually acute distally and ending in a short, straight, 0.6–1 mm on beak, tan, ochre, light-bown or turning black with age, apically dehiscent, the valves papery but stiff, glabrous, the septum complete, 0.4–0.5 mm wide; seeds 1.2–1.6 × 1.1–1.2 mm, mitten shapped, olive, orange-olive to brown-reddish, opaque.

Distribution:— Endemic to Mexico, in the municipios of Cuernava and Huitzilac in the state of Morelos ( Fig. 24 ).

Habitat:— Pine forest, tropical rain forest; 2600 m.

Comments: Species related to the perennial A. guatemalensis and A. strigulosus . Astragalus sagitticarpus cand be differentiated from those species by its almost black minute calyx teeth and shorter pod.

Specimens examined:— MORELOS: 10 November 1978, Municipio Huitzilac, Km 74 carretera (antigua) México-Cuernavaca, O. Téllez 526 ( MEXU) ; 25 October 1981, Km 76 carretera México-Cuernavaca, Mpio. Cuernavaca, A. Leyva 411 ( ENCB) ; 17 February 2011, Coajomulco, Km 58 carr. México-Cuernavaca, Mpio. Huitzilac, T. González O. 9 ( ENCB) .

Figures

FIGURE 24. Map showing the distribution of Astragalus regiomontanus, A. rupertii, A. sabulonuum, A. sagitticarpus, and A. sanctorum in Mexico.