Aquatic invertebrate communities in tank bromeliads: how well do classic ecological patterns apply?

Tank bromeliads (Bromeliaceae) often occur in high densities in the Neotropics and represent a key freshwater habitat in montane forests, housing quite complex invertebrate communities. We tested the extent to which there are species richness–altitude, richness–environment, richness–size, richness–habitat complexity and richness–isolation relationships for the aquatic invertebrate communities from 157 bromeliads in Cusuco National Park, Honduras. We found that invertebrate species richness and abundance correlated most strongly, and positively, with habitat size, which accounted for about a third of the variance in both. Apart from bromeliad size (equivalent of the species– area relationship), we found remarkably little evidence of classic biogeographic and ecological relationships with species richness in this system. Community composition correlated with altitude, bromeliad size and position, though less than 20% of the variation was accounted for by the tested variables. The turnover component of dissimilarity between the communities correlated with altitude, while the nestedness-resultant component was related to bromeliad size. The unexplained variance could reflect a large stochastic component in the system, associated with the ephemerality of the habitat patches (both the plants themselves and the fluctuations in their water content) and stochasticity due to the dispersal dynamics in the system. We conclude that there is a small contribution of classic biogeographic factors to the diversity and community composition of aquatic invertebrates communities in bromeliads. This may be due to the highly dynamic nature of this system, with small patch sizes and high emigration rates. The patterns may mostly be driven by factors affecting colonisation success

A new species of <i>Ocyale</i> (Araneae, Lycosidae) from Madagascar, with first observations on the biology of a representative in the genus

A large white species of wolf spider, Ocyale ghost Jocque M. & Jocque R. sp. nov., is described from a white sandy beach of an inland freshwater lake in the northwest of Madagascar. The first photos of a living specimen of the genus Ocyale are provided together with some observations on the biology of the newly described species. An updated and illustrated key to the Afrotropical species of Ocyale is included here

Pools "on the rocks" : freshwater rock pools as model system in ecological and evolutionary research

Rock pools inarguably exhibit a number of characteristics which make them attractive as a model system in ecological and evolutionary research. They are usually small, pristine, clearly delineated and structurally simple systems that occur on a global scale. They facilitate the quantification of important population and community structuring processes which are often hard or impossible to quantify in larger more complex systems. Basic properties and spatial configuration of rock pools also closely resemble theoretical metapopulation and metacommunity models. Due to the simple morphometry of rock pool basins and the lack of any groundwater interactions, rock pool hydrologies are simple allowing to reliably reconstruct the disturbance regime against which patterns of variation in life histories, population genetics, species diversity and community structure can be interpreted.Sin lugar a dudas las pozas en rocas presentan numerosas características que las hacen atractivas para su uso como sistema modelo en la investigación evolutivo-ecológica. Normalmente son sistemas vírgenes de pequeño tamaño, estructuralmente sencillos y claramente delineados, que se encuentran a escala global. Permiten la cuantificación de importantes procesos estructuradores de poblaciones y comunidades que, a menudo, son muy difíciles o imposibles de cuantificar en sistemas mayores más complejos. Las propiedades básicas y la configuración espacial de las pozas en rocas también muestran una estrecha semejanza con los modelos teóricos de metapoblación y metacomunidad. Debido a la morfometría simple de las cubetas de estas pozas y a la carencia de interacciones con las aguas subterráneas, las hidrologías de estas pozas son de poca complejidad, lo que permite reconstruir con fiabilidad el régimen de perturbación determinante de los patrones de variación de los ciclos de vida de los organismos, de la genética de poblaciones, diversidad de especies y estructura de comunidades

Dominant predators mediate the impact of habitat size on trophic structure in bromeliad invertebrate communities

Local habitat size has been shown to influence colonization and extinction processes of species in patchy environments. However, species differ in body size, mobility, and trophic level, and may not respond in the same way to habitat size. Thus far, we have a limited understanding of how habitat size influences the structure of multitrophic communities and to what extent the effects may be generalizable over a broad geographic range. Here, we used water-filled bromeliads of different sizes as a natural model system to examine the effects of habitat size on the trophic structure of their inhabiting invertebrate communities. We collected composition and biomass data from 651 bromeliad communities from eight sites across Central and South America differing in environmental conditions, species pools, and the presence of large-bodied odonate predators. We found that trophic structure in the communities changed dramatically with changes in habitat (bromeliad) size. Detritivore : resource ratios showed a consistent negative relationship with habitat size across sites. In contrast, changes in predator : detritivore (prey) ratios depended on the presence of odonates as dominant predators in the regional pool. At sites without odonates, predator : detritivore biomass ratios decreased with increasing habitat size. At sites with odonates, we found odonates to be more frequently present in large than in small bromeliads, and predator : detritivore biomass ratios increased with increasing habitat size to the point where some trophic pyramids became inverted. Our results show that the distribution of biomass amongst food-web levels depends strongly on habitat size, largely irrespective of geographic differences in environmental conditions or detritivore species compositions. However, the presence of large-bodied predators in the regional species pool may fundamentally alter this relationship between habitat size and trophic structure. We conclude that taking into account the response and multitrophic effects of dominant, mobile species may be critical when predicting changes in community structure along a habitat-size gradient.Fil: Petermann, Jana S.. Freie Universitat Berlin. Institute of Biology; AlemaniaFil: Farjalla, Vinicius F.. Universidade Federal do Rio de Janeiro; BrasilFil: Jocque, Merlijn. State University Of New Jersey; Estados UnidosFil: Kratina, Pavel. Queen Mary University Of London. School of Biological and Chemical Sciences; Reino UnidoFil: Macdonald, Andrew. University Of British Columbia; CanadáFil: Marino, Nicholas. Universidade Federal do Rio de Janeiro; BrasilFil: de Omena, Paula. Universidade Estadual de Campinas; BrasilFil: Piccoli, Gustavo. Universidade de Sao Paulo; BrasilFil: Richardson, Michael. Universidad de Puerto Rico; Puerto RicoFil: Richardson, Barbara. Universidad de Puerto Rico; Puerto RicoFil: Romero, Gustavo. Universidade Estadual de Campinas; BrasilFil: Videla, Martin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Córdoba. Instituto Multidisciplinario de Biología Vegetal (p); Argentina. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales. Centro de Investigaciones Entomológicas de Córdoba; ArgentinaFil: Srivastava, Diane. University Of British Columbia; Canad

The new Southeast Asian genus Cambonilla gen. nov. (Zodariidae, Araneae): bis repetita placent

The new genus Cambonilla Jocqué gen. nov. is described on the base of two species, each known from both sexes. A cladistic analysis based on morphology, showed that the new genus is the sister-group of Heliconilla Dankittipakul, Jocqué & Singtripop, 2012 with which it shares the granulated carapace with branched setae and the marbled ventral abdominal pattern, but differs by the abdominal, tubular sclerotized protrusion around the pedicel in males and the absence of posterior ventral abdominal spines in the female. The type species Cambonilla securicula Jocqué gen. et sp. nov. was found in rainforest along the Mekong River in Cambodia and Laos. The second species Cambonilla symphonia Jocqué & Henrard gen. et sp. nov., provided with conspicuous femoral stridulating organs, was recorded from the same localities but in Cambodia only. An illustrated key to the genera of tropical Asia is presented

The value of eco-volunteer projects for biodiversity conservation - butterfly monitoring in Krka National Park (Croatia) with an updated checklist

The biogeographical importance of Dalmatia, bordered by the Dinaric Alps and the Adriatic Sea, is evident through the rich biodiversity of this region and its network of protected areas. One of those areas, Krka National Park (NP), supports a wide range of natural habitats, but rapidly increasing tourism puts high pressure on its ecosystems, despite its protected status. Accurate knowledge of species and their distributions within natural places such as Krka is essential to direct and prioritize future conservation efforts. As collecting biodiversity data is time and resource-intensive, alternative ways to obtain this information are needed. One possibility is monitoring based on eco-volunteering. From June to August of 2019, an Operation Wallacea/BIOTA scientific team surveyed a section of Krka NP and its surrounding boundaries, within the vicinity of the village of Puljane, to study its butterfly richness and abundance. Pollard walks and static count surveys were conducted with the help of eco-volunteers, testing the effectiveness of gathering field data through this approach. Overall, 57 butterfly species were found throughout the study, including four new records for Krka NP. Three further new species for the park were detected close to its boundaries and are also expected to occur within its borders. Here, we present an updated butterfly checklist for Krka NP, highlighting the positive impact of eco-volunteering initiatives and the importance of combined research efforts to study and protect the rich biodiversity and ecosystems of protected areas.info:eu-repo/semantics/publishedVersio

Modelling Hurricane Exposure and Wind Speed on a Mesoclimate Scale: A Case Study from Cusuco NP, Honduras

High energy weather events are often expected to play a substantial role in biotic community dynamics and large scale diversity patterns but their contribution is hard to prove. Currently, observations are limited to the documentation of accidental records after the passing of such events. A more comprehensive approach is synthesising weather events in a location over a long time period, ideally at a high spatial resolution and on a large geographic scale. We provide a detailed overview on how to generate hurricane exposure data at a meso-climate level for a specific region. As a case study we modelled landscape hurricane exposure in Cusuco National Park (CNP), Honduras with a resolution of 50 m×50 m patches. We calculated actual hurricane exposure vulnerability site scores (EVVS) through the combination of a wind pressure model, an exposure model that can incorporate simple wind dynamics within a 3-dimensional landscape and the integration of historical hurricanes data. The EVSS was calculated as a weighted function of sites exposure, hurricane frequency and maximum wind velocity. Eleven hurricanes were found to have affected CNP between 1995 and 2010. The highest EVSS's were predicted to be on South and South-East facing sites of the park. Ground validation demonstrated that the South-solution (i.e. the South wind inflow direction) explained most of the observed tree damage (90% of the observed tree damage in the field). Incorporating historical data to the model to calculate actual hurricane exposure values, instead of potential exposure values, increased the model fit by 50%

How useful are volunteers for visual biodiversity surveys? An evaluation of skill level and group size during a conservation expedition

The ability of volunteers to undertake different tasks and accurately collect data is critical for the success of many conservation projects. In this study, a simulated herpetofauna visual encounter survey was used to compare the detection and distance estimation accuracy of volunteers and more experienced observers. Experience had a positive effect on individual detection accuracy. However, lower detection performance of less experienced volunteers was not found in the group data, with larger groups being more successful overall, suggesting that working in groups facilitates detection accuracy of those with less experience. This study supports the idea that by optimizing survey protocols according to the available resources (time and volunteer numbers), the sampling efficiency of monitoring programs can be improved and that non-expert volunteers can provide valuable contributions to visual encounter-based biodiversity surveys. Recommendations are made for the improvement of survey methodology involving non-expert volunteers

Toward a Global Phylogeny of the “Living Fossil" Crustacean Order of the Notostraca

Tadpole shrimp (Crustacea, Notostraca) are iconic inhabitants of temporary aquatic habitats worldwide. Often cited as prime examples of evolutionary stasis, surviving representatives closely resemble fossils older than 200 mya, suggestive of an ancient origin. Despite significant interest in the group as ‘living fossils’ the taxonomy of surviving taxa is still under debate and both the phylogenetic relationships among different lineages and the timing of diversification remain unclear. We constructed a molecular phylogeny of the Notostraca using model based phylogenetic methods. Our analyses supported the monophyly of the two genera Triops and Lepidurus, although for Triops support was weak. Results also revealed high levels of cryptic diversity as well as a peculiar biogeographic link between Australia and North America presumably mediated by historic long distance dispersal. We concluded that, although some present day tadpole shrimp species closely resemble fossil specimens as old as 250 mya, no molecular support was found for an ancient (pre) Mesozoic radiation. Instead, living tadpole shrimp are most likely the result of a relatively recent radiation in the Cenozoic era and close resemblances between recent and fossil taxa are probably the result of the highly conserved general morphology in this group and of homoplasy