 |
| Astragalus sagitticarpus A.E. Estrada, Villarreal & Encina
in Castillón, Quintanilla & Domínguez, 2020.
|
Abstract
We describe and illustrate Astragalus sagitticarpus A.E. Estrada, Villarreal & Encina (Fabaceae) as a new species from south-central Mexico. Its annual habit, free stipules, few leaves, small calyx teeth, and pendulous, persistent, stipitate, dorsoventrally compressed pod characterize this species. Added to other characteristics related to the other sections, but not in the same combination of them, such as habit, flower size, and union of the stipules allow recognizing a new section also.
Keywords: Leguminosae, section Sagitticarpi, south-central Mexico, Eudicots
 |
| FIGURE 1. Holotype (MEXU 1219252) of Astragalus sagitticarpus. |
 |
| FIGURE 2. Astragalus sagitticarpus, A) Whole plant showing leaves, inflorescences, flowers and fruits. B) Stipules. C) Bracts. D) Calyx. E) Banner front view (left) and profile (right). F) Wing. G) Keel. H) Stamens. I) Ovary. J) Fruit. |
Astragalus sect. Sagitticarpi A. E. Estrada, Villarreal & Encina, sect. nov.
Type:— Astragalus sagitticarpus A. E. Estrada, Villarreal & Encina
Etymology:— The name Sagitticarpi of this new section comes from the shape of the fruit, similar to an arrowhead.
This new section is monospecif (monotypic). We added a dichotomous key in order to recognize and differentiate it
from the other sections in Mexico (adapted from Barneby 1964). The key includes only those sections with free
stipules.
Astragalus sagitticarpus A.E. Estrada, Villarreal & Encina spec. nov.
Etymology:— The name of the species refers to the characteristic shape of the fruit, which resembles an arrowhead,
flattened dorsoventrally, elliptical to oval, straight, basally gradually narrowing, ending in a stipe, distally gradually
acute, ending in a short, straight beak.
Distribution and habitat:— As currently known, there is only one specimens existent of Astragalus sagitticarpus collected in the type locality near to the highway Cuernavaca-Mexico, growing in pine forest stands (Fig. 3).
Eduardo Estrada Castillón, José Ángel Villarreal Quintanilla and Juan Antonio Encina Domínguez. 2020. A New Species and A New Section of Astragalus (Fabaceae: Papilionoideae) from Mexico. Phytotaxa. 428(3); 163–172. DOI: 10.11646/phytotaxa.428.3.1
