A Taxonomic Revision of Heterosperma (Asteraceae: Coreopsideae)

LIZARAZU, MABEL A.; FREIRE, SUSANA E.

ANNALS OF THE MISSOURI BOTANICAL GARDEN

MISSOURI BOTANICAL GARDEN

Año: 2019 vol. 104 p. 633 - 663

0026-6493

The New World genus Heterosperma Cav. is circumscribed to include 11 species: H. achaetum S. F. Blake, H. diversifoliumKunth, H. ferreyrii H. Rob., H. mexicanum (A. Gray ex S. Watson) Lizarazu & S. E. Freire, H. nanum (Nutt.) Sherff, H. ovale S. F.Blake, H. ovatifolium Cav., H. pinnatum Cav., H. spathulatum S. F. Blake, H. tenuisectum (Griseb.) Cabrera, and H. trilobum S. F.Blake. Heterosperma is described as having a usually herbaceous habit, pinnatisect or entire leaves, radiate capitula, andheteromorphic cypselae. The following taxa are newly synonymized: Coreopsis L. sect. Anathysana S. F. Blake with Heterosperma;H. maritimum Kunth var. hirsuta Hieron. with H. ovatifolium; and H. maritimum var. latifolia Hieron. with H. spathulatum.Lectotypes are here designated for H. maritimum var. hirsuta, H. pinnatum var. typicum Kuntze, H. tagetinum A. Gray,H. spathulatum, and H. maritimum var. latifolia. A key to the species of the genus is provided, as well as morphologicaldescriptions, illustrations, and distribution maps. A detailed morphological study of trichomes and pappus is also presented.