New Indo-Pacific species of Rimosodaphnella Cossmann, 1916 (Gastropoda: Conoidea): a genus of probable Tethyan origin

The genus Rimosodaphnella Cossmann, 1916 was proposed for Murex textile Brocchi, 1814, a European Miocene–Pliocene species, and is sometimes thought to be represented in the recent fauna by three Atlantic species. Here, we assign only one Atlantic species, Pleurotoma (Drillia) morra Dall, 1881 distributed from North Carolina to Southern Brazil, to the genus and introduce three new species of Rimosodaphnella from the Indo-Pacific region. One, Rimosodaphnella solomonensis, n. sp. from the Solomon Islands, while two others, Rimosodaphnella tenuipurpurata n. sp. and Rimosodaphnella brunneolineata n. sp., from the Philippines Islands; these findings suggest that the genus may be well represented in the Indo-Pacific region.

http://zoobank.org/urn:lsid:zoobank.org:pubBD6E8AA4-445C-43A5-8171-65A7CE8BA20B     

An estimate of potential threats levels to soil biodiversity in EU

Life within the soil is vital for maintaining life on Earth due to the numerous ecosystem services that it provides. However, there is evidence that pressures on the soil biota are increasing which may undermine some of these ecosystem services. Current levels of belowground biodiversity are relatively poorly known, and so no benchmark exists by which to measure possible future losses of biodiversity. Furthermore, the relative risk that each type of anthropogenic pressures places on the soil biota remains unclear. Potential threats to soil biodiversity were calculated through the use of a composite score produced from data collected from 20 international experts using the budget allocation methodology. This allowed relative weightings to be given to each of the identified pressures for which data were available in the European Soil Data Centre (ESDC). A total of seven different indicators were used for calculating the composite scores. These data were applied through a model using ArcGIS to produce a spatial analysis of composite pressures on soil biodiversity at the European scale. The model highlights the variation in the composite result of the potential threats to soil biodiversity. A sensitivity analysis demonstrated that the intensity of land exploitation, both in terms of agriculture and use intensity, as well as in terms of land‐use dynamics, were the main factors applying pressure on soil biodiversity. It is important to note that the model should not be viewed as an estimate of the current level of soil biodiversity in Europe, but as an estimate of pressures that are currently being exerted. The results obtained should be seen as a starting point for further investigation on this relatively unknown issue and demonstrate the utility of this type of model which may be applied to other regions and scales.     

Wetlands serve as natural sources for improvement of stream ecosystem health in regions affected by acid deposition

For over 40 years, acid deposition has been recognized as a serious international environmental problem, but efforts to restore acidified streams and biota have had limited success. The need to better understand the effects of different sources of acidity on streams has become more pressing with the recent increases in surface water organic acids, or ‘brownification,’ associated with climate change and decreased inorganic acid deposition. Here, we carried out a large scale multi‐seasonal investigation in the Adirondacks, one of the most acid‐impacted regions in the United States, to assess how acid stream producers respond to local and watershed influences and whether these influences can be used in acidification remediation. We explored the pathways of wetland control on aluminum chemistry and diatom taxonomic and functional composition. We demonstrate that streams with larger watershed wetlands have higher organic content, lower concentrations of acidic anions, and lower ratios of inorganic to organic monomeric aluminum, all beneficial for diatom biodiversity and guilds producing high biomass. Although brownification has been viewed as a form of pollution, our results indicate that it may be a stimulating force for biofilm producers with potentially positive consequences for higher trophic levels. Our research also reveals that the mechanism of watershed control of local stream diatom biodiversity through wetland export of organic matter is universal in running waters, operating not only in hard streams, as previously reported, but also in acid streams. Our findings that the negative impacts of acid deposition on Adirondack stream chemistry and biota can be mitigated by wetlands have important implications for biodiversity conservation and stream ecosystem management. Future acidification research should focus on the potential for wetlands to improve stream ecosystem health in acid‐impacted regions and their direct use in stream restoration, for example, through stream rechanneling or wetland construction in appropriate hydrologic settings.     

Conservation implications of divergent global patterns of ant and vertebrate diversity

Aim

Global conservation planning is often oriented around vertebrates and plants, yet most organisms are invertebrates. To explore the potential conservation implications of this bias, we assessed how well patterns of diversity for an influential group of invertebrates, the ants, correspond with those of three vertebrate groups (birds, mammals and amphibians).

Location

Global.

Methods

We compiled data on the number of genera of ants and the three vertebrate groups for 370 political regions across the world. We then compared their correlations both for overall diversity and between subsets of genera likely to be of conservation concern. We also developed generalized additive models (GAM) to identify regions where vertebrates and ants diverged in their diversity patterns.

Results

While ant and vertebrate diversity do positively correlate, the correlations are substantially weaker for the ant lineages of the greatest conservation concern. Vertebrates also notably fail to predict ant diversity in specific geographic areas, including Australia and Southeast Asia, parts of Africa and Madagascar, and south‐western China. These failures may be genuine differences in diversity patterns, or they may indicate important gaps in our knowledge of ant and vertebrate diversity.

Main conclusions

We conclude that it is currently unwise to assume that global conservation priorities based on vertebrates will conserve ants as well. We suspect that this also applies to other invertebrates.

     

Heavy metal pollution negatively correlates with anuran species richness and distribution in south‐eastern Australia

Heavy metal pollution has likely played an important role in global biodiversity decline, but there remains a paucity of information concerning the effects of metals on amphibian diversity. This study assessed anuran species richness and distribution in relation to sediment metal content and water chemistry in wetlands located along the Merri Creek corridor in Victoria, south‐eastern Australia. Anurans were present in 60% (21/35) of study sites, with a total of six species detected: the eastern common froglet (Crinia signifera), the eastern sign‐bearing froglet (Crinia parinsignifera), the southern brown tree frog (Litoria ewingii), the growling grass frog (Litoria raniformis), the eastern banjo frog (Limnodynastes dumerilii) and the spotted marsh frog (Limnodynastes tasmaniensis). Mean species richness was 1.77 ± 0.32 per site, and species richness ranged from zero to six species per site. Across sites, species richness correlated negatively with sediment concentrations of six heavy metals: copper, nickel, lead, zinc, cadmium and mercury. Species richness also correlated negatively with wetland water electrical conductivity (a proxy for salinity) and concentrations of orthophosphate. Distributions of the three most commonly observed frog species (C. signifera, L. tasmaniensis and L. ewingii) were significantly negatively associated with the total level of metal contamination at individual sites. The study is the first to provide evidence for an association between metal contamination and anuran species richness and distribution in the southern hemisphere, adding to a small but growing body of evidence that heavy metal pollution has contributed to global amphibian decline.     

Individual dispersal,landscape connectivity and ecological networks

Connectivity is classically considered an emergent property of landscapes encapsulating individuals' flows across space. However, its operational use requires a precise understanding of why and how organisms disperse. Such movements, and hence landscape connectivity, will obviously vary according to both organism properties and landscape features. We review whether landscape connectivity estimates could gain in both precision and generality by incorporating three fundamental outcomes of dispersal theory. Firstly, dispersal is a multi‐causal process; its restriction to an ‘escape reaction’ to environmental unsuitability is an oversimplification, as dispersing individuals can leave excellent quality habitat patches or stay in poor‐quality habitats according to the relative costs and benefits of dispersal and philopatry. Secondly, species, populations and individuals do not always react similarly to those cues that trigger dispersal, which sometimes results in contrasting dispersal strategies. Finally, dispersal is a major component of fitness and is thus under strong selective pressures, which could generate rapid adaptations of dispersal strategies. Such evolutionary responses will entail spatiotemporal variation in landscape connectivity. We thus strongly recommend the use of genetic tools to: (i) assess gene flow intensity and direction among populations in a given landscape; and (ii) accurately estimate landscape features impacting gene flow, and hence landscape connectivity. Such approaches will provide the basic data for planning corridors or stepping stones aiming at (re)connecting local populations of a given species in a given landscape. This strategy is clearly species‐ and landscape‐specific. But we suggest that the ecological network in a given landscape could be designed by stacking up such linkages designed for several species living in different ecosystems. This procedure relies on the use of umbrella species that are representative of other species living in the same ecosystem.     

Loss of small glaciers will diminish beta diversity in Pyrenean streams at two levels of biological organization

Aim Small (< 1 km²) alpine glaciers are likely to disappear in this century, resulting in decreased regional habitat heterogeneity in associated streams. Both heterogeneity within and spatial isolation among glacier‐influenced streams can enhance beta diversity of stream‐dwelling organisms. We measured beta at both community and population‐genetic levels within and among streams currently influenced by small Pyrenean glaciers. We aimed to evaluate whether patterns are analogous between the two levels, to apply various approaches for characterizing beta, and to infer the outcome of future glacier loss on regional biodiversity. Location Four glacier‐fed basins in the Parc National des Pyrénées, France. Methods We classified each of 18 stream reaches across the basins into either high‐, mid‐ or low‐‘glaciality’ (glacial influence) groups according to four physicochemical characteristics. At each reach, we collected macroinvertebrate communities and evaluated mitochondrial DNA haplotypes for 11–13 individuals of Baetis alpinus Pictet. Using taxa/haplotypes as basic units, we evaluated community and population‐genetic beta diversity simultaneously. We measured beta diversity in three major ways: as multivariate (Sørensen's dissimilarity, Jost D) and ‘classical’ (gamma/alpha) variation to compare among glaciality groups, and as turnover along the glaciality gradient within each basin. Results For most approaches at both organizational levels, beta was greatest among high‐glaciality reaches, absolute values of variation of beta in high‐glaciality streams were strikingly similar between levels, and the steepest turnover within basins occurred between high‐ and mid‐glaciality reaches. Therefore, high‐glaciality reaches contained assemblages and populations that were unique both within that stream type (among basins) and compared with other stream types within basins. Main conclusions Parallel beta diversity patterns at population‐genetic and community levels suggested that environmental drivers influence these levels analogously. Extreme conditions (e.g. low temperature, high instability, isolation) in high‐glaciality streams probably enhance beta at both levels. Stream beta diversity is likely to decrease substantially with continued glacial reduction in this system.     

Taxonomic,phylogenetic and ecological diversity of Niphargus (Amphipoda: Crustacea) in the Hölloch cave system (Switzerland)

Groundwater belongs to the spatially most extensive, but least explored freshwater systems. On a global scale, the species richness of several subterranean invertebrate taxa parallels species richness found in surface waters, while on a local scale species richness hardly exceeds 20 species. This results in a high contribution of groundwater ecosystems to regional β- and γ-diversity, and to a smaller degree to α-diversity, and deserves focused attention. In general, more species are to be found in large cave systems. The second largest cave system in Europe is Hölloch in Switzerland. In this paper we revised the taxonomic, phylogenetic and ecological diversity of the amphipod community in the Hölloch cave system. While previous records listed five geographically widespread species of the genus Niphargus for this cave system, we could not confirm the presence of any of those species, but rather found three highly distinct species new to science. In this paper we describe Niphargus styx sp. nov., Niphargus murimali sp. nov., and Niphargus muotae sp. nov., and suggest that previous records from that cave were probably misidentifications. Although amphipod species richness in this cave system seems to be lower than previously thought in terms of absolute numbers, the cave retained its regional and international importance in terms of nature conservation for multiple reasons. First, all newly described species are probably endemic to this cave system. Second, they are phylogenetically distantly related and exhibit moderate to high phylogenetic diversity. Third, the species, as inferred from their functional morphology, are also ecologically highly divergent. Based on geographic distribution of their nearest relatives, we hypothesize that the cave system was most likely independently colonized from North, West and South and that the pre-adapted ancestors occupied different ecological niches within the system.

http://zoobank.org/urn:lsid:zoobank.org:pub:A19309E5-C06B-4844-A4D8-7571F05F25C9     

Diversity and community structure of bats (Chiroptera) in the Centre Region of Cameroon

In this survey, we investigated the diversity and community structure of bats in the Centre Region of Cameroon with respect to their distribution in the different vegetation zones of the region. We mist-netted bats monthly from January 2016 to June 2017 for five nonconsecutive nights per month. Thirty-nine sites were surveyed: 24 in traditional farms, nine in the savannah and six in the forests. A total of 668 bats were captured during 81 nights of capture, covering seven families, 21 genera and 36 species. This included 26 species in traditional farms, 13 species in savannah and 11 species in the forest. Micropteropus pusillus was the most abundant species (30.7%) recorded, followed by Hipposideros ruber (24.9%). The sample efficiency was estimated at 72.1% with fitted species accumulation curves not reaching asymptotes for the three habitat types, suggesting that the survey did not record all the bats present. There was an indication of general increased in abundance of bats during the dry and rainy seasons but it is not significant (Mann–Whitney U: 783.5, p = .195). The rarity index was highest in traditional farms (0.44), followed by savannah (0.38) and then forest (0.33). This preliminary survey provides baseline data on the distribution of bats in the different vegetation types in the Centre Region of Cameroon.