Malvaviscus Fabr.
Contenido
Descripción
Branching shrubs or small trees, sometimes scandent, pubescent or glabrous. Leaves petiolate, the blades elliptic, ovate, or 3-5-lobed, truncate or cordate, lacking foliar nectaries; stipules subulate, deciduous. Flowers solitary in the leaf axils or sometimes in apical cymelike groups; bractlets of the involucel linear, lanceolate, or spatulate, usually (5-) 8-9; calyx campanulate or tubular, 5-lobed; petals red (rarely white), auriculate toward the base, forming a tubular corolla; androecium usually exserted, the staminal column with 5 apical teeth, the filaments short and more or less retrorse; styles 10 with capitate stigmas. Fruit a fleshy schizocarp or berry, oblate, usually red, with 5 carpels, each 1-seeded. Base chromosome number: x = 14.A
Discusión taxonómica
Comprising one or a dozen species depending on interpretation, Malvaviscus is a difficult genus in need of a modern revision. It occurs from Texas and the West Indies to South America, with its greatest diversity in Mexico and Central America. Some forms are widely cultivated for their showy flowers. Standley and Steyermark (1949) say, “There is perhaps no group of Central American and Mexican plants where taxonomy is so unsatisfactory at present, and it is never likely to be in a more satisfactory state.” In part [ agree with this assessment. Although it is possible to discern certain modal expressions that are more or less discrete, it is very difficult to delimit such taxa in an unequivocal way. The genus itself is well characterized, especially by its auriculate petals and fleshy fruits, as well as by its general aspect. But there is a certain sameness of morphology that runs through the genus, and clear-cut differentiating characters are lacking. The following treatment, therefore, attempts to recognize the more easily discerned forms and to characterize them as well as possible, but acknowledges that it is not a wholly satisfactory interpretation of the group. There remains a certain amount of intergradation among the taxa here recognized and a residue of variation that is not accounted for, especially within M. arboreus var. mexicanus, the most common taxon of this genus in Mexico. I hope that this interpretation will prove to be more useful than those previously available.A