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Chorizanthe angustifolia var. eastwoodiae was named by Goodman in 1934, but has since generally been ignored as a taxon. A limited number of C. angustifolia var. angustifolia collections available for comparison and lack of clearly defined characters differentiating the two varieties likely account for the taxonomic concept for C. angustifolia that rejects infraspecific taxa. Nevertheless, several characters previously unnoted in floristic literature distinguish var. angustifolia from var. eastwoodiae. Variety angustifolia is a yellow-green plant with straw-colored tepals that are narrow and long-pointed, and has 3 stamens per flower. Variety eastwoodiae is a pinkish plant with pink, rounded and often erose tepals, with 8–9 stamens per flower. Morphological differences and comparative DNA sequencing indicate the two varieties are better treated as separate species. A new combination (C. eastwoodiae comb. et stat. nov.) is proposed and typification of the name C. angustifolia is clarified. A comparison table of closely related Chorizanthe is provided.

En el marco de una revision de Chorizanthe R. Br. ex Benth. (Polygonaceae—Eriogonoideae) para el proyecto Nueva Flora de Chile, se describen cinco especies nuevas para la ciencia: C. gajardoi Teillier & Macaya, C. mieresii Teillier & Macaya, C. navasiae Teillier & Macaya, C. novoana Teillier & Macaya y C. rosasii Teillier & Macaya, se trata de hierbas perennes o subarbustos, camefitos. Las cinco especies son endemicas del norte de Chile y crecen entre las regiones administrativas de Coquimbo y Valparaiso. Como todas las especies lenosas o herbaceas perennes del genero en el pais, ellas pertenecen al subgenero Chorizanthe.

The nuclear ribosomal internal transcribed spacer and chloroplast rbcL-accD intergenic spacer regions of species in the Pungentes subsection of Chorizanthe (spineflower) were analyzed. The goals of the study were to ascertain the phylogenetic relationships of taxa in the C. pungens-C. robusta complex to each other and to the other Pungentes species. The ITS phylogenies showed that C. diffusa was most distant from the other species and that C. cuspidata, C. pungens and C. robusta were not monophyletic. The four varieties of the C. pungens-C. robusta complex resolved into montane and coastal groups but the groupings were not in agreement with current classification. Statistical parsimony analysis divided 26 chloroplast DNA haplotypes into four groups with the 18 sampled populations of the C. pungens-C. robusta complex displaying a high degree of phylogeographic structure despite some incomplete lineage sorting. The haplotype analysis was not discordant with the ITS phylogeny. Possible taxonomic rev...

Spatial and temporal variation in critical life history traits differ markedly between two co-occurring, rare and endangered annual plants, Gilia tenuiflora arenaria and Chorizanthe pungens pungens, that have restricted, but overlapping geographic distributions in coastal habitats of central California, USA. Environmental variation was extreme during the 6-year study (1997–2002), with the greatest differences between an intense wet, warm El Nino year (1998), followed by a very dry, cool La Nina (1999). Both species have similar increases in adult survival and seed set with wetter, warmer weather in spring, but they differed in other traits: more Gilia germinated in years with high rainfall and temperature, while more Chorizanthe germinated in dry, cooler years; Gilia abundance increased with the number of years since the previous large El Nino event, while Chorizanthe abundance declined; and Gilia abundance was independent of the previous year’s seed set, while Chorizanthe density was directly related to the previous year’s seed set. The strong negative associations of Chorizanthe abundance with warm, wet weather and with time since the previous El Nino probably reflect the particular sequence of annual weather patterns from 1997 through 2002, especially the extremes in 1998 and 1999. Since it germinates readily in most years under a wide range of winter conditions and does not develop a long-lived seed bank, Chorizanthe seedling abundance reflects recent additions and depletions of its seed bank, rather than prevailing weather, per se. In contrast, Gilia seeds may remain in the seed bank for many years, until relatively rare winter conditions trigger significant germination. These species-specific demographies enhance persistence and coexistence of these species, but the mechanisms differ from each other and from those described for annuals in other highly variable environments.

Species with known demographies may be used as proxies, or approximate models, to predict vital rates and ecological properties of target species that either have not been studied or are species for which data may be difficult to obtain. These extrapolations assume that model and target species with similar properties respond in the same ways to the same ecological factors, that they have similar population dynamics, and that the similarity of vital rates reflects analogous responses to the same factors. I used two rare, sympatric annual plants (sand gilia [Gilia tenuiflora arenaria] and Monterey spineflower [Chorizanthe pungens pungens]) to test these assumptions experimentally. The vital rates of these species are similar and strongly correlated with rainfall, and I added water and/or prevented herbivore access to experimental plots. Their survival and reproduction were driven by different, largely stochastic factors and processes: sand gilia by herbivory and Monterey spineflower by rainfall. Because the causal agents and processes generating similar demographic patterns were species specific, these results demonstrate, both theoretically and empirically, that it is critical to identify the ecological processes generating observed effects and that experimental manipulations are usually needed to determine causal mechanisms. Without such evidence to identify mechanisms, extrapolations among species may lead to counterproductive management and conservation practices. Resumen: Las especies con demografias conocidas pueden ser utilizadas como modelos aproximados para predecir tasas vitales y propiedades ecologicas de especies que no han sido estudiadas o cuyos datos no pueden ser obtenidos facilmente. Estas extrapolaciones asumen que el modelo y la especie blanco con propiedades similares responden de la misma forma a los mismos factores ecologicos, que pueden tender dinamicas poblacionales similares y que la similitud de las tasas vitales refleja respuestas analogas a los mismos factores. Utilice dos plantas anuales simpatricas y raras Gilia tenuiflora arenaria y Chorizanthe pungens pungens para probar estos supuestos experimentalmente. Las tasas vitales de estas especies son similares y estan correlacionadas estrechamente con la precipitacion, y agregue agua y/o evite el acceso de herbivoros a las parcelas experimentales. Su supervivencia y reproduccion fueron influidas por diferentes factores y procesos, en gran parte estocasticos: G. t. arenaria por la herbivoria y C. p. pungens por la precipitacion. Debido a que los agentes y procesos causales que generaron patrones demograficos similares fueron particulares para cada especie, estos resultados demuestran, tanto teorica como empiricamente, que es critico identificar los procesos ecologicos que generan efectos observados y que se requieren manipulaciones experimentales para determinar mecanismos causales. Sin tal evidencia para la identificacion de mecanismos, las extrapolaciones a otras especies pueden conducir a practicas de manejo y conservacion contraproducentes.

Uromyces intricatus is broken into six varieties. Var. umbellati and var. major attack montane and lowland species of Eriogonum subgen. Eueriogonum in much of western North America, and the former probably attacks Oxytheca. Vars. intricatus (Oregon, California), parvifolii (California), nivei (interior British Columbia to Arizona), and pluriporosus (mainly Montana, Wyoming, and Colorado) attack various species or species groups in Eriogonum subgen. Oregonium, the variation being partly geographic and partly due to host specialization. Var. intricatus attacks Chorizanthe spp. and Eriogonum subgen. Ganysma in California. This variety has met and intergraded with var. pluriporosus in the past but the link is now broken. Uromyces bisbyi, a microcyclic derivative of var. parvifolii, is described on Eriogonum parvifolium in California. The implications on the evolution of Eriogonum and the problem of realistic nomenclature of rusts derived from both host and geographic isolation are discussed. A table clarifies the nomenclature of reported host plants.

Reviewing the floral relations of North and South America as illustrated in the foregoing instances, we may say that the phenomena of distribution agree fairly with the record of physical conditions which have succeeded each other and those which still exist, and upon which we might almost a priori have predicted an analogous set of distribution phenomena. In this relationship we may distinguish three categories of distribution: (1) Those due to the conditions of human civilization, commerce, etc. This has resulted in placing the same species in similar regions of both continents, as, for example, Fagonia cretica in Lower California and Chile; Munroa squarrosa, western plains of North America, plains of Argentine and high plateaus of Chile and Bolivia; Frankenia grandiflora, Southern California and Arizona, coast lands of Chile; Oxytheca dendroidea, Lastarricea chilensis, and Chorizanthe comrnmissuralis, all in Southern California and Western Chile. (2) Those due to the operation of natural causes acting unde present conditions of climate, geology, etc. Under this head may be cited such species as sida leprosa, hastata, anomala, Cienfugosia sulphurea, Spergulariaplattensis and, in general, elements of Gulf zone distribution; also certain elements which still find a pathway along the continental axis, including some alpine and mountain xerophilous genera. (3) The third category of distribution would include those phenomena due to geological and climatic changes acting through long periods. Under this head are included the elements of greatest significance in the relationsip of the North and South America floras. The endemic boreal flora of the Andes, the equally endemic boreal flora of the Mexican Cordilleras, and genera with sharply distinct species or sub-genera in the arid extra-tropical regions of both continents, which may be called remnant elements.