Sphaeralcea A. St.-Hil.
Contenido
Descripción
Herbs or shrubs, erect (or less often procumbent), usually perennial, stellate pubescent, frequently with numerous stems. Leaves petiolate, the blades lanceolate, ovate, or orbicular, sometimes hastate or palmately parted, lacking foliar nectaries; stipules inconspicuous. Inflorescences racemose, paniculate, or thyrsoid; pedicels usually shorter than the calyces; involucel of three linear bracts; calyx 5 lobed, usually pubescent; corolla about twice the length of the calyx, yellow, orange, rose, or purple; androecium included, pale yellow or purple, antheriferous at apex, the column usually pubescent; styles 10-16, the stigmas capitate. Fruits schizocarpic, oblate or truncate-conic, pubescent; mericarps usually (7-) 10-16, apiculate or rounded apically, usually differentiated into two parts (except S. endlichi?), the lower part reticulate and indehiscent, the upper part smooth and dehiscent; seeds 1-3 per carpel, more or less pubescent, the hairs very short. Base chromosome number: x = 5A
Discusión taxonómica
Sphaeralcea includes about 40 species and has a disjunct distribution. It occurs in the western United States as far north as 50° latitude and in northern Mexico and, disjunctly, in temperate South America, especially in Argentina and adjacent countries; it is thus principally distributed in the temperate zone. About 20 species may be found in Mexico.A