Deinandra

Abstract: IEMIZONIA IS A genus of the tribe Madiinae of the family Compositae. Commonly known as the tarweeds, its members are confined in their distribution largely to California including the coastal islands, and partly to adjacent Oregon, Nevada and Baja California. As reconstituted by Keck (unpublished) the genus consists of four sections: Zonamra, Deinandra, Centromadia and Hemizonia. In the earlier taxonomic treatment of Jepson (1925), the spikeweeds, Centromadia, were accorded generic status. Keck (1935) recognized four species under Centromadia: Hemnizonia pungens (Hk. et Arn.) Torr. et Gray, H. parryi Greene, H. fitchii Gray and H. perennis (Greene) Keck. Characters of the pappus, anthers, bracts, inflorescence and herbage are used to distinguish the taxa. Hemizonia pungens has no pappus on its disk florets, H. parryi has three pappus bristles per disk floret and H. fitchii has many. The chromosome ntumbers previousl y recorded are n 9 for H. pungens, n 11 and 12 for H. parryi and n 13 for H. fitchii (Clausen, Keck and Heusi, 1934). The chromosome number of H. perennis is unknown; unlike the other species, it is a perennial and is known from only two localities in Baja California. Figure 1 shows the relative distribution of the species and subspecies. Hemizonia pungens, by far the commonest member of the section, is widely distributed. At least in California, there are three distinct forms of this species which occur in more or less distinct ecological niches and are taxonomically treated as subspecies. The maritime form, H. pungens ssp. mnaritima Keck occurs chiefly in salt marshes around San Francisco bay and along the coast, but is rare elsewhere. Hemizonia pungens ssp. interior Keck, an inland form occurring in the dry inner valleys, is very abundant throughout the San Joaquin and Salinas valleys and probably has been introduced along the western borders of the Mojave desert. The populations occurring in the passes of the Inner Coast Range which separates the two subspecies, contain many intermediates and recombinations. Hemizonia pungens ssp. laevis is

Abstract: New combinations and new genera for species in Hemizonia DC., Madia Molina, and Raillardiopsis Rydberg allow for a revised, practical taxonomy of Madiinae that better reflects phylogenetic relationships. Reinstatement of Anisocarpus Nuttall, Centromadia Greene, Deinandra Greene, and Hemizonella A. Gray, abandonment of Raillardiopsis Rydberg, and recognition of four new genera (Carlquistia, Harmonia, Jensia, Kyhosia) for tarweed lineages without available generic names result from changes in circumscription based on monophyletic groups. Results of phylogenetic, biosystematic, and cytogenetic studies in Madiinae (Kyhos et al., 1990; Baldwin et al., 1991; Baldwin, 1992, 1993, 1996, unpublished; Carr et al., 1996) indicate that Hemizonia DC. sensu Keck (1959), Madia Molina sensu Keck (1959), and Raillardiopsis Rydberg are not monophyletic. Hemizonia sensu Keck (1959) comprises a minimum of three monophyletic groups that correspond to section Centromadia (Greene) D. D. Keck, section Hemizonia, and section Madiomeris Nuttall sensu Tanowitz (1982) plus the informal "Fruticosae" or "Zonamra" (cf. Clausen, 1951; Keck, 1959). Madia sensu Keck (1959), Raillardiopsis, and the monophyletic Hawaiian silversword alliance (Argyroxiphium DC., Dubautia Gaudichaud-Beauprd, Wilkesia A. Gray; see Carr, 1985) constitute a clade lacking a formal name (the "Madia" lineage in Baldwin, 1996) that is extremely heterogeneous and difficult to diagnose morphologically. The Hawaiian group comprises trees, shrubs, subshrubs, large rosette plants, mat plants, cushion plants, and vines that are strikingly divergent in morphological and ecological characteristics from the primarily Californian herbs in Madia sensu Keck (1959) and Raillardiopsis (see Carr, 1985; Baldwin & Robichaux, 1995; Baldwin, 1997). In addition to the distinctive Hawaiian lineage, a minimum of seven monophyletic groups can be reliably diagnosed from morphological and molecular data within the clade comprising Madia sensu Keck (1959), Raillardiopsis, and the silversword alliance. Recognition at the generic level of each of the three lineages in Hemizonia sensu Keck (1959) and each of the seven lineages in the paraphyletic group comprising Madia sensu Keck (1959) plus Raillardiopsis in the traditional (only) sense results in a practical taxonomy that conforms to the criterion of monophyly (= holophyly) of taxa. The revision of Madia sensu Keck (1959) plus Raillardiopsis (hereafter, MADRAIL) also allows for continued generic distinction of the unusual Hawaiian species in the silversword alliance without maintaining non-monophyletic California tarweed genera. I realize that additional nomenclatural changes in the silversword alliance are necessary to achieve a taxonomy of the Hawaiian species that includes only monophyletic genera. The new combinations herein focus only on genera relevant to treatments in preparation for the Flora of North America North of Mexico.

Abstract: A new combination, Deinandra peninsularis (Moran) B. G. Baldwin, comb. nov., is proposed for D. greeneana subsp. peninsularis of Baja California, Mexico, a taxon that does not belong within D. greeneana, based on recent molecular and cytogenetic work. New chromosome counts for D. peninsularis and D. streetsii and previously reported counts for the other 20 species of Deinandra indicate that all perennial or facultatively perennial taxa of the genus share the modal, and probably basal, chromosome number of 2n = 12II. A new chromosome count for another member of the tarweed tribe, Arnica mallotopus [≡ Mallotopus japonicus] (2n = 19II), in Arnicinae, strongly contrasts with an earlier (somatic) count for that species (2n = 18), which is often treated in a different genus based in part on the previously reported chromosome number.