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Chorizanthe fue descrito por G. Bentham (1836) sobre la base de plantas recolectadas en Chile. Las primeras especies descritas fueron C. glabrescens Benth., C. macraei Benth., C. paniculata Benth., C. peduncularis Benth., C. vaginata Benth. y C. virgata Benth. J. Rémy (1851) las reconoce y agrega a C. frankenioides J. Rémy y a C. commissuralis J. Rémy. R.A. Philippi (1864, 1873, 1895) describió unas dieciséis especies de las que aún se aceptan, C. dasyantha Phil, C. flavescens Phil., C. kingii Phil., C. umbellata Phil. y C. viridis. J. Reveal (2004) llevó a cabo una revisión y sinonimización de los tipos y propuso catorce especies como válidas para Chile; sin embargo, no revisó el género ni presentó claves de determinación. Teillier y Macaya (2018) describieron cinco especies en el marco de una revisión para el proyecto “Nueva Flora de Chile”: C. gajardoi Teillier & Macaya, C. mieresii Teillier & Macaya, C. navasiae Teillier & Macaya, C. novoana Teillier & Macaya y C. rosasii Teillier & Macaya. En este trabajo se describe una nueva especie, C. limariensis y se presenta una revisión, la primera integral, con el fin de proponer una hipótesis sobre la taxonomía del género. Para ello se han utilizado los métodos clásicos comparando tipos, material de herbario y ejemplares en terreno. Como resultado se propone que el género estaría formado por 19 especies, 18 subarbustos y hierbas perennes (subgénero Chorizanthe) y una anual (C. commissuralis, subgénero Amphietes). Se lectotipifica, además, a C. fasciculata Phil., C. kingii Phil., C. parviflora Phil., C. rosea Phil. y C. viridis Phil. Finalmente, se presentan una clave para diferenciar las especies, descripciones morfológicas y fotografías.

Resumen.: En el marco de una revisión 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, caméfitos. Las cinco especies son endémicas del norte de Chile y crecen entre las regiones administrativas de Coquimbo y Valparaíso. Como todas las especies leñosas o herbáceas perennes del género en el país, ellas pertenecen al subgénero Chorizanthe. During a review of Chorizanthe R. Br. ex Benth. (Polygonaceae–Eriogonoideae) for the "New Flora of Chile" project, five new species of Chorizanthe were discovered: C. gajardoi Teillier & Macaya, C. mieresii Teillier & Macaya, C. navasiae Teillier & Macaya, C. novoana Teillier & Macaya, and C. rosasii Teillier & Macaya. These are all perennial herbs or chamaephytic subshrubs endemic to northern Chile between the administrative regions of Coquimbo and Valparaiso. Like all Chilean woody or herbaceous perennial species of the genus, they belong to Chorizanthe subg. Chorizanthe. [ABSTRACT FROM AUTHOR]

* Premise of the study: Most seed dispersal studies focus on the spatial aspects of propagule dissemination, i.e., the movement of seeds away from the mother plant. However, the timing of seed release can also be a critical variable influencing the probability of seedling survival. We used a biomechanical approach to analyze seed release in Chorizanthe rigida, a serotinous desert annual, to understand the adaptive significance of seed retention in this species. * Methods: We performed pull-to-break tests on individual propagules (i.e., involucres and achene) from newly developed and older plants, under dry and wet conditions, and recorded the breaking force. We measured the involucral base area using digital images and image processing software. * Key results: There is a positive correlation between the force required to detach an involucre and the size of its base area. The force required to detach involucres from soaked and older plants was lower than that for dry and new plants. This pattern provides a mechanism for the plant to regulate the number of involucres released in different rain events. * Conclusions: Seed release in C. rigida is mediated by propagule morphology, rainfall conditions, and age of the dry plant. These factors allow this species to cope with desert environmental variability by influencing the timing and number of seeds released. [ABSTRACT FROM AUTHOR]

Coccoloba berazainae, a new species from E Cuba, is described, illustrated and compared with another Cuban endemic species, C. acuna. The status of C. nervosa subsp. cristalensis, also endemic to E Cuba, is discussed. It is compared with typical C. nervosa, raised in rank, and treated as a separate species, C. cristalensis. [ABSTRACT FROM AUTHOR]

Abstract: We studied the small scale distribution pattern of Chorizanthe rigida, a serotinous desert annual, in a shrub-mound-to-desert-pavement gradient. Two sites were established in the Mojave Desert and two sites where established in the Sonoran Desert. We placed transects along a soil surface gradient from shrub mounds to desert pavements, and measured land surface properties, soil characteristics, and C. rigida's small scale distribution. A Principal Components Analysis was done on the resulting site × soil variables matrix. C. rigida established preferentially in desert pavements outside shrub canopies. Pavements showed finer soil textures and higher electrical conductivities, while shrub mounds had sandy textures, low surface rockiness, higher nitrogen, and higher cover of annuals. We discuss a probable relationship between seed retention and the establishment on desert pavements: timing seed release allows this species to avoid wind- or animal-induced seed dispersal into shrub mounds and establish outside the nurse mounds, where most annual plants concentrate. The seeds encased in the serotinous involucres, released after rains, are dispersed by run-off into the desert pavements and transition zones where, once developed, the dead seed-retaining structures of adult C. rigida plants persist for years releasing seeds to subsequent rain events. [Copyright &y& Elsevier]

The article presents a study which examines the phylogenetic relationships among Eriogonoideae s. s. The study made used of the Cetyltrimethyl Ammonium Bromide (CTAB) protocol to extract the DNA. The result of the study shows that most of the taxonomic groups were shown to be non-monophyletic in phylogenies.

Coccoloba howardii, a new species from the north-central region of Cuba, is described and illustrated. It appears to be closely related to C. subcordata, from which it differs primarily in the spiral arrangement of the short branches and leaf features such as the petiole inserted at the base of the ochrea, a membranous blade and alternate primary veins not grouped at the base. [ABSTRACT FROM AUTHOR]

In this experiment we tested the effects of some vegetable extracts (biopreparations) of Polygonum aviculare L.(knotgrass) and Polygonum bistorta L.(meadow bistort), from the Polygonaceae family, on some vital organs, in experimental rats. The duration of experiment was of 10 days, when we have daily gavaged a group of femal Wistar rats, with 1 ml vegetable extract of Polygonum aviculare, prepared from plant's aerial part and the other group also received 1 ml vegetable extract of Polygonum bistorta, from the caudices of the plant. After 10 days rats were sacrificed and blood samples were taken for determination of serum transaminases activity (GPT and GOT). Also, were removed samples of brain - hipotalamus, adrenal glands, liver, kidney and thin gut (duodenum). From adrenals was determined the cholesterol content. At the analyzed organs level was made the histology with help of hematoxylin - eosine staining emphasizing the neuro - endocrine - pituitary - adrenal axis reaction. The metabolic organs as the liver, kidney and duodenum were also investigated through the determination of some enzymes activity such are: lactate dehidrogenase, succinat-dehidrogenase, Mg-dependent adenosine triphosphatase, cytochromoxidase. The obtained results were grouped analyzed, after methodologies. Thus, on the biochemical plans, the GPT level doesn't have a significantly modification, but diminishes the GOT level into treated groups. The cholesterol content in adrenals doesn't modify. As concern the histologic structure of analized organs we point out, in forerank, at the pituitary level, an easier stimulation of neuro-endocrine secretion at the neuron level and on the axonal route, but without any pathologically signification. In the remainder, the structure of the analyzed organs there is any pathological modifications in adrenals, liver, kidney and duodenum. As concern analyzed histochemical and histoenzymological activity it doesn't modify in vegetable extracts treated groups compared with control group, with a little exception, namely, in the treated groups at the duodenum level the ATP-ase activity is easier increased compared with the control group. In conclusion, the administration of Polygonum aviculare and Polygonum bistorta extracts don't produces any pathological effects at the neuro-endocrine axis level and in the metabolic studied organs. There are no differences between the action of those two vgetable extracts obtained from different species, at least in our experimental conditions. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

This vegetation study describes the landscape of the San Felipe Desert (Baja California, México) based on the phytosociological analysis of its major plant associations, as determined by the Braun-Blanquet method and supported by cluster analysis. Four geomorphological or phytotopographical units were identified in the landscape of the San Felipe Desert (salt marshes, playas or sandy flats, bajadas or alluvial fans, and malpaíses or badlands), each characterized by its own plant communities. Two communities and eleven associations were identified, four of which are described and typified for the first time: Atriplici linearis-Frankenietum palmeri, Parkinsonio microphyllae-Olneyetum tesotae, Errazurizio megacarpae-Ephedretum trifurcae and Pachycereo schottii-Prosopidetum torreyanae. Ecological, phytogeographical, bioclimatic, syntaxonomical and floristic data are provided for each of these new associations. [ABSTRACT FROM AUTHOR]

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 Niño year (1998), followed by a very dry, cool La Niña (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 Niño 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 Niño 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. [ABSTRACT FROM AUTHOR]

The article reports on the critical habitat designations issue in California. In a lawsuit filed against the U.S. Fish & Wildlife Service (USFWS) concerning the issue, the Pacific Legal Foundation has announced that it had met an agreement with the USFWS that it requires the agency to reassess the critical habitat designations for five species of threatened or endangered species in the state. Reassessment will be done on species like Monterey spineflower, San Bernardo kangaroo rat, and the La Graciosa thistle.