A new tiger beetle from the Gulf Coast of Texas (Coleoptera, Cicindelidae, Cicindelini)

A new tiger beetle species, Eunota albicauda Duran, Roman & Huber n. sp., of the tribe Cicindelini, is described from the Gulf Coast of southern Texas. It is superficially most similar to E. togata (LaFerté-Sénectère, 1841) and E. circumpicta (LaFerté-Sénectère, 1841) but is distinguished on the basis of multiple character states not shared with either species. We reconstructed a phylogeny for Eunota to address the placement of this new taxon. Little is known about the biology or distribution of this exceedingly rare species. Despite extensive tiger beetle collecting from this region, only two specimens of E. albicauda n. sp. are known, collected in the mid-20th century. Future efforts to locate additional specimens should focus on coastal salt flats and marshes in southern Texas, including areas near the United States-Mexico border, late in the season (September-October).

Metabolic Potential of Microbial Communities in the Hypersaline Sediments of the Bonneville Salt Flats

The Bonneville Salt Flats (BSF) appear to be entirely desolate when viewed from above, but in reality they host rich microbial communities just below the surface salt crust. In this study, we investigate the metabolic potential of the BSF microbial ecosystem. The predicted and measured metabolic activities provide new insights into the ecosystem functions of evaporite landscapes and are an important analog for potential subsurface microbial ecosystems on ancient and modern Mars. Hypersaline and evaporite systems have been investigated previously as astrobiological analogs for Mars and other salty celestial bodies. Still, these studies have generally focused on aquatic systems and cultivation-dependent approaches. Here, we present an ecosystem-level examination of metabolic pathways within the shallow subsurface of evaporites. We detected aerobic and anaerobic respiration as well as methanogenesis in BSF sediments. Metagenome-assembled genomes (MAGs) of diverse bacteria and archaea encoded a remarkable diversity of metabolic pathways, including those associated with carbon fixation, carbon monoxide oxidation, acetogenesis, methanogenesis, sulfide oxidation, denitrification, and nitrogen fixation. These results demonstrate the potential for multiple energy sources and metabolic pathways in BSF and highlight the possibility for vibrant microbial ecosystems in the shallow subsurface of evaporites.

Differentiation of Diatom Guilds in Extreme Environments in the Andean Altiplano

The Andean Altiplano is characterized by its isolation, high altitude (>3,600 m a.s.l.), and a unique biodiversity, containing water systems such as lakes, rivers, wetlands, and salt flats. Near the southernmost area of the Andean Altiplano are two salt flats, Carcote and Ascotán, the former almost undisturbed by human intervention and the latter historically intervened with by brine mining. These mining activities deplete, pollute, and alter water flow, suggesting a significant threat to ecosystem functions. With regard to identifying the main factors promoting biotic community differentiation in these salt flats at different levels of human intervention, the aim of this study was to compare diatom community indices by guild (high-profile, low-profile, and motile) between these systems with a functional perspective, their relationship to environmental conditions, and the potential anthropic impact on their community structures. Diatom guilds were compared between salt flats based on their diversity, species richness, and abundance relative to ionic concentrations and granulometry. Beta diversity and the percentages of nestedness and turnover for each guild were also estimated. Results showed significant differences in ecological variables between the two salt flats. The largest values of species abundance, richness, and diatom diversity were measured in Carcote, suggesting greater primary productivity and diversity. The results also showed that the species composition of the motile guild was more differentiated between salt flats than those of other guilds (with the greatest diversity and richness), suggesting that motile diatoms are a key guild in maintaining the diatom community and that species from this guild are more sensitive to local conditions from each salt flat. Additionally, beta diversity in all guilds was mainly explained by turnover rather than nestedness, and the turnover was the highest for the motile and low-profile guilds. A more heterogeneous community was observed in Ascotán, showing that the mechanisms of diversity maintenance, such as dispersion abilities, were salt flat dependent. This suggests that the highest diversity could be related to human use, which challenges us to reexamine the effectiveness of past conservation activities in the area and to develop future strategies including both connected basins.

Electrical conductivity as a driver of biological and geological spatial heterogeneity in the Puquios, Salar de Llamara, Atacama Desert, Chile

Reputed to be the driest desert in the world, the Atacama Desert in the Central Andes of Northern Chile is an extreme environment with high UV radiation, wide temperature variation, and minimum precipitation. Scarce lagoons associated with salt flats (salars) in this desert are the surface expression of shallow groundwater; these ponds serve as refugia for life and often host microbial communities associated with evaporitic mineral deposition. Results based on multidisciplinary field campaigns and associated laboratory examination of samples collected from the Puquios of the Salar de Llamara in the Atacama Desert during austral summer provide unprecedented detail regarding the spatial heterogeneity of physical, chemical, and biological characteristics of these salar environments. Four main lagoons (‘Puquios’) and more than 400 smaller ponds occur within an area less than 5 km2, and are characterized by high variability in electrical conductivity, benthic and planktonic biota, microbiota, lagoon bottom type, and style of mineral deposition. Results suggest that electrical conductivity is a driving force of system heterogeneity. Such spatial heterogeneity within the Puquios is likely to be expanded with temporal observations incorporating expected seasonal changes in electrical conductivity. The complexity of these Andean ecosystems may be key to their ability to persist in extreme environments at the edge of habitability.

Analysis of Replicability of Conservation Actions across Mediterranean Europe

In the Regional Park of Las Salinas and Arenales of San Pedro del Pinatar, in southeastern Spain, an environmental restoration and conservation project is being developed whose principle actions include adaptation of hillocks with a saline substrate to improve the reproduction habitat of aquatic birds and increasing the production of salt, dune restoration and conservation, protection of the first dune ridge through the collection of seagrass tops, and designing and implementation of a salt quality seal, which may be useful for reproduction in other sites in the Natura 2000 network, especially in the European Mediterranean area and in the Black Sea environment. The objective of this research study was to analyse and locate the sites that could possibly replicate the actions of the project. In order to do this, spatial databases were used from the Natura 2000 network, salt flats, and marshes as well as Ramsar sites and SPAMI sites, and from them a shape file of points was created in the places with the presence of maritime dunes associated with marsh systems/salt flats. One hundred thirty-one sites in the Natura 2000 network were located, of which in 105 cases, one or more of the four actions considered in this research study can be replicated. Of these, 24 cases have active or recently abandoned salt flats in which the two main actions of the project can be replicated, and 11 of these sites meet characteristics for the replicability of the four actions, of which three have not been implemented by the LIFE projects developed on those sites.