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Evidence is presented about the presence of Phaseolus microcarpus in Costa Rica, while it was previously reported northwards in other Central American countries and Mexico. Fourteen populations are currently known, four from the Peninsula of Nicoya, and ten are in the tropical dry forest of the mainland of this country. [ABSTRACT FROM AUTHOR]

In the arid and semiarid region of Mexico, data on three native grasses growing in diverse ecological environments--Muhlenbergia peruviana (P. Beauv.) Steud., in temperate forests; Bouteloua gracilis (Kunth) Lag. ex Griffiths, in grasslands; Muhlenbergia porteri Scribn. ex Beal, in xeric regions; and one introduced nonnative species, Melinis repens (Willd.) Zizka (Zizka rose Natal grass)--were used in our essay analyzing their potential distribution, based on climatic factors. We took presence-only data applied to the Bioclim algorithm included in the Diva-GIS program. Using database bioclimatic WorldClim-Global Climate Data allowed us to make predictions of the distribution, and to determine the climatic characteristics that each species needs to grow. It generated a potential distribution of the four species under study, concluding that this method can be applied to other grass species from this geographic area in order to improve: a) knowledge of the actual distribution of species in their natural environment, b) knowledge related to biodiversity, and c) to create an indicator to support decisions related to conservation and management of grasses in Mexico. We concluded that possibly climatic requirements prevent the expansion of the introduced species (Zizka rose, Natal grass). [ABSTRACT FROM AUTHOR]

To better understand the potential distribution of Taxus globosa Schlecht., we used a conifer species with restricted distribution, listed on the NOM-059-SEMARN AT-2010, a modeling distribution procedure of maximum entropy or MaxEnt, based on 40 occurrences of field records and 39 REMIB -CONABIO records. Two different scenarios of geographical and environmental coverages--climatic and topographic--were proved statistically. The BIOCLIM variables scenario with topography data show a more accurate model in the range of 0.9 to 1.0 probability with a 55% coincidence; it was statistically significant at (AUC=0.985). Slope variable indicates an environmental variable with more influence in potential modeling, followed by Bio14 (Precipitation of Driest Month). In agreement with the MaxEnt analysis with 19 BIOCLIM and 3 topographic variables, the main plant communities in the modeling area (where Taxus globosa is distributed in Mexico) are pine-oak forest, oak-pine forest, pine forest, and cloud mesic forest. Taxus globosa is potentially distributed in Hidalgo, Nuevo León, Puebla, Tamaulipas, and Veracruz. [ABSTRACT FROM AUTHOR]

The geographic and host distributions of Arceuthobium hondurense and A. nigrum (Viscaceae) in southern Mexico and Central America have remained unclear due to difficulties in their identification. This study was conducted to clarify the morphology, phenology, distribution, and host affinities of these dwarf mistletoes. Morphological measurements were made for these species across their geographic distributions and nr ITS sequences were generated and compared from selected populations in Mexico. Although subtle, interspecific differences in plant morphology were found, A. hondurense and A. nigrum can be differentiated by the dimensions of their staminate spikes, staminate flowers, and fruits. Our data also indicated that A. hondurense and A. nigrum were not sympatric. Arceuthobium hondurense is distributed from northern Nicaragua to northern Oaxaca, Mexico and A. nigrum is distributed from Veracruz to northern Durango. Although A. hondurense and A. nigrum flowered in the fall, A. hondurense consistently peaked in September and A. nigrum peaked in October, extending into January in central Mexico. A spring flowering period reported previously for A. nigrum was not observed. Additional information on the host distribution and molecular differences of these dwarf mistletoes is also presented. [ABSTRACT FROM AUTHOR]

New localities of geographic distribution for two grasses of Mexico are presented. Muhlenbergia filiculmis Vasey, a species known only in the West of United States is registered for the first time in Mexico. So is the distribution of Distichlis eludens (Soderstr. & H.F. Decker) H.L. Bell & Columbus, is expanded into a regional level, since it has been recently collected in Zacatecas, Mexico. [ABSTRACT FROM AUTHOR]