The Status of Aster commixtus and a New Species of Aster from the Southeastern United States

Abstract

Multivariate statistical techniques are used to show that the type specimen of Eurybia commixta Nees (=Aster commixtus (Nees) Kuntze) belongs to A. spectabilis Aiton. The two species are, therefore, conspecific and the names E. commixta and A. commixtus are later synonyms for A. spectabilis. Statistical analyses also demonstrate that the plants native to the southeastern United States to which the name A. commixtus has been applied do not belong to A. spectabilis, but to two other distinct species, the diploid A. mirabilis Torrey & A. Gray, and a previously unnamed hexaploid species, A. jonesiae Lamboy, described here as new. Historically, Aster commixtus (Nees) Kuntze has always been placed in or close to the group now known as Aster sect. Biotia DC. ex Torrey & A. Gray (Lamboy and Jones 1987a), but both the origin and the identity of the species have been uncertain. Nees von Esenbeck (1832) orig- inally described the species as Eurybia commixta, placing it (along with Aster macrophyllus L., A. schreberi Nees, A. corymbosus Aiton, and another new species, E. glomerata Bernh. ex Nees) in the Genuinae group of the genus Eurybia (Cass.) Cass. in Cuvier. His description of E. commixta was based on a plant of unknown provenance that had been grown in the Bonn Botanical Garden. Nees characterized the species as follows: rad- ical leaves narrow; lower cauline leaves ovate; upper cauline leaves oblong-lanceolate, ses- sile, serrate, viscid-scabrous; capitulescence branched; phyllaries squarrose; pubescence glutinous (i.e., stipitate-glandular). No holo- type of this name exists, but an authentic Nees specimen has recently been designated as the lectotype (Lamboy and Jones 1987b). From Nees's Genuinae group in Eurybia, de