Many hemipteran species are phytophagous, feeding on plant sap. This is true of the family Membracidae, many species of which engage in mutualistic interactions with ants, providing them with honeydew in exchange for protection against natural enemies. These interactions often attract the interest of amateur and professional photographers due to the aesthetic appeal of the organisms involved, but they are rarely formally reported. Here, we present several cases of trophobiosis observed in the Mexican states of Chiapas and Quintana Roo between the ant Ectatomma tuberculatum and several membracid genera. Seven myrmecophilous hemipteran species belonging to the subfamilies Membracinae (Guayaquila gracilicornis, Guayaquila sp., Bolbonota pictipennis, Enchenopa binotata, E. squamigera, Membracis mexicana) and Smiliinae (Vanduzea segmentata) are reported here, all of which are subsocial or communal. Although most of the species mentioned are already known to be associated with the genus Ectatomma or have been previously recorded on iNaturalist or other online citizen science databases, some represent the first formal report of an association with E. tuberculatum. Like most Ectatomma species, E. tuberculatum is essentially carnivorous but also scavenges on dead prey and exploits sugar sources. Its attraction to honeydew combined with the communal or subsocial behavior of many treehoppers —which concentrates sugary sources in specific parts of its habitat— certainly explains the wide variety of facultative trophobiotic interactions recently reported between this ant and Membracidae in French Guiana and now in Mexico. Further systematic observations and studies, as well as careful review of photo banks, should uncover many more such interactions.
Failing to consider power relations in social processes can represent a major barrier for effective transformation toward sustainable and just futures. Although this has been widely acknowledged in the scientific literature, there are few attempts to unravel the role of power relations for social-ecological systems management. We present an analysis of the different types of power relations and their effects in a multi-actor network that stewards a protected area in Xalapa, Mexico. Moreover, we explored how different participatory research methods can impact these power relations. Following the Foucault concept of micro-power and using a mixed qualitative and quantitative methodological approach, we classified power relations according to epistemic, ethical, and political dimensions. We identified a complex fabric of subtle power relations that reproduce socio-political patterns and limit the participation of certain types of actors, weakening the multi-actor organization and its potential for transformation. We found that constructing horizontalities requires not only a consensual intention but also collaborative practices capable of dismantling power relations and creating common grounds for multiple types of encounters between diverse actors. We conclude that power relations constitute a central element of multi-actor organizations and, when adequately addressed, contain great potential for radical transformation.
In this study, we examined ostracode biodiversity and species taxonomy, based on morphological characteristics, from the sulfate-bicarbonate rich, oligotrophic, and freshwater Bacalar hydrological system. A total of 19 species belonging to five subfamilies were identified. Here, we describe five new species: Cypris nicte Macario-González & Cohuo sp. nov., Pseudocandona tzabek Macario-González & Cohuo sp. nov., Thalassocypria zazilha Macario-González & Cohuo sp. nov., Dolerocypria maanik Macario-González & Cohuo sp. nov., and Cyprideis ichkabal Macario-González & Cohuo sp. nov. These species are clearly distinguished from their congeners by valve outline, overall shape, or appendages morphology, particularly the male sexual appendages. Thalassocypria Hartmann, 1957, Dolerocypria Tressler, 1937, Perissocythere Stephenson, 1938, and Cyprideis Jones, 1857 are distributed worldwide only in estuarine, anchialine, and marine environments. However, their continued presence in the Bacalar system at sporadically sampling for a decade suggests that the species have successfully colonized, naturalized to freshwater, and becoming established residents, likely supported by the carbonate-related high conductivity waters. We discuss the hypothetical mechanisms underlying their inland colonization and highlight the relevance of Bacalar system as a potential ecological niche supporting their freshwater establishment and distribution.
Bioregionalisation is a hierarchical system that categorises geographical areas according to their biotic composition and evolutionary history. While a global bioregionalisation has been proposed for angiosperms, this is lacking for plant families with global relevance, such as orchids. We used 732 359 orchid distribution records and a phylogeny of 19 123 species to define the global bioregionalisation of orchids based on phylogenetic beta diversity at 200 × 200 km resolution. Using the resulting bioregionalisation, we analysed the environmental drivers that determine the formation of realms. Additionally, we assessed the effect of sampling completeness, different metrics, and spatial resolutions. We identified six global orchid realms (Australian, Andean-Patagonian, Neotropical, Afrotropical, Indo-Malaysian, and Holarctic) and 10 bioregions; four main transition zones were also detected. Mean annual precipitation and temperature, and precipitation and temperature seasonality, had the strongest influence on the delimitation of realms. We present a global bioregionalisation for orchids, identifying the environmental factors that determine the realms. More generally, these results highlight the importance of bioregionalisation for understanding evolutionary patterns of taxonomic families. Using a comprehensive seven-step methodology, we emphasize the need to account for sampling completeness and spatial resolution in such analyses.
