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Telmatoblechnum, with the species Telmatoblechnum serrulatum (Blechnaceae), is recorded for the first time for the Uruguayan flora. The species, so far known from southern Brazil and Northeastern Argentina as its southernmost distribution limit, was collected for the first time in crevices between rocks of basalt and sandstone in a small hill in Uruguay (Rivera). Its morphological characteristics and the novel habitat for the species are included; photographs, a map with the location of the new record, as well as a key to the genera of Blechnaceae in Uruguay are provided. [ABSTRACT FROM AUTHOR]

Global warming, coupled with habitat destruction and human activity, are accelerating the rates of species extinction worldwide. Species-extinction risk assessment using the IUCN Red List categories, together with the study of the spatial patterns of biodiversity, are fundamental approaches for identifying conservation priorities and targeting government decisions to mitigate impacts on biodiversity. Here, we analyzed the geographic distribution of Argentinean species of Brassicaceae using species point distributional data. In this way, we classified species following the IUCN threat categories at a regional level, and analyzed patterns of richness, endemism, and threat on the different ecoregions and biomes of the country. In addition, we also explored differences in elevation, annual mean temperature, annual precipitation, and aridity between endemic vs. non-endemic and threatened vs. non-threatened species. The results showed that of the 162 Argentinean taxa, 58 species were here categorized as threatened (VU, EN, or CR) (36%). However, when only endemics are considered, more than half of these (33 spp, 57%) are threatened. Although species inhabit all environments and biogeographic regions of the country, arid to semi-arid areas, which are associated to the Andes and the Patagonian steppe, contained most of the species. Specifically, the Central Andean Puna and the Patagonian steppe ecoregions included the greatest number of species, endemics, and threatened species. Furthermore, different hotspots of richness, endemism, and threat were detected along Andean regions and the Patagonian steppe, and endemics were characterized by inhabiting on average drier areas than non-endemic native species. An up-to-date species list, including conservation status, distribution maps for all species, hotspots of richness, endemism, and threat, are also provided. This work seeks to contribute to the knowledge on geographical patterns of the Argentinean flora and its conservation, complementing the information published in the Flora of Argentina. [ABSTRACT FROM AUTHOR]

Rúgolo de Agrasar recognized two varieties of Deyeuxia velutina (D. velutina var. velutina and D. velutina var. nardifolia) based on leaf sheath indumentum, lemma length, and leaf blade direction. However, taxonomic delimitation has been difficult due to occasional overlapping characters. To assess the infraspecific delimitation of D. velutina, we present a comprehensive study combining morphometric analyses and a potential distribution model. To explore morphological variation and select diagnostic characters, we measured 124 morphological characters in 52 specimens of both varieties and performed a principal coordinate analysis and univariate analyses (Analysis of variance and Kruskal-Wallis nonparametric test). Both taxa resolved as separate morphological groups. Additionally, a Discriminant Analysis was performed to classify the individuals in the predetermined morphological groups. For modeling the species distribution, 26 specimens of D. velutina var. nardifolia and 68 of D. velutina var. velutina were georeferenced and 20 environmental variables were analyzed through a Maximum Entropy model. Deyeuxia velutina extends in the high Andean region from Peru to southern Argentina and Chile. Both varieties differed in their geographical limits, a result supported by regression analyses of latitude and longitude on the principal coordinates of the PCoA. Deyeuxia velutina var. nardifolia is restricted to the northern area of distribution while D. velutina var. velutina showed a higher habitat suitability in the southern region. Moreover, D. velutina var. nardifolia is here reported for the first time in San Juan province (Argentina), constituting the austral limit of its geographical distribution. Additional reliable morphological characters were considered in an updated key to the varieties. [ABSTRACT FROM AUTHOR]