Search

Quaternary climate fluctuations can affect biodiversity assembly through speciation in two non-mutually-exclusive ways: a glacial species pump, where isolation in glacial refugia accelerates allopatric speciation, and adaptive radiation during ice-free periods. Here we detected biogeographic and genetic signatures associated with both mechanisms in the generation of the European Alps biodiversity. Age distributions of endemic and widespread species within aquatic and terrestrial taxa (amphipods, fishes, amphibians, butterflies and flowering plants) revealed that endemic fish evolved only in lakes, are highly sympatric and mainly of Holocene age, consistent with adaptive radiation. Endemic amphipods are ancient, suggesting preglacial radiation with limited range expansion and local Pleistocene survival, perhaps facilitated by a groundwater-dwelling lifestyle. Terrestrial endemics are mostly of Pleistocene age, and are thus more consistent with the glacial species pump. The lack of evidence for Holocene adaptive radiation in the terrestrial biome may be attributable to a faster range expansion of these taxa after glacial retreats, though fewer stable environments may also have contributed to differences between terrestrial areas and lakes. The high proportion of young, endemic species make the Alps vulnerable to climate change, but the mechanisms and consequences of species loss will likely differ between biomes because of their distinct histories.

Sex allocation theory predicts that the proportion of daughters to sons will evolve in response to ecological conditions that determine the costs and benefits of producing each sex. All else being equal, the adult sex ratio (ASR) should also vary with ecological conditions. Many studies of subterranean species reported female-biased ASR, but no systematic study has yet been conducted. We test the hypothesis that the ASR becomes more female-biased with increased isolation from the surface. We compiled a data set of ASRs of 35 species in the subterranean amphipod Niphargus, each living in one of three distinct habitats (surface-subterranean boundary, cave streams, phreatic lakes) representing an environmental gradient of increased isolation underground. The ASR was female-biased in 27 of 35 species; the bias was statistically significant in 12 species. We found a significant difference in the ASR among habitats after correction for phylogeny. It is most weakly female-biased at the surface-subterranean boundary and most strongly female-biased in phreatic lakes. Additional modelling suggests that the ASR has evolved towards a single value for both surface-subterranean boundary and cave stream-dwelling species, and another value for 9 of 11 phreatic lake dwellers. We suggest that a history of inbreeding in subterranean populations might lower inbreeding depression such that kin selection favours mating with siblings. This could select for a female-biased offspring sex ratio due to local mate competition among brothers. The observed patterns in sex ratios in subterranean species make them a group worthy of more attention from those interested in sex allocation theory.

Knowledge on the diversity and distribution of subterranean organisms is still scattered, even in faunistically relatively well-researched countries such as Switzerland. This is mostly due to the restricted access to these subterranean habitats. Better knowledge on these organisms is needed, because they contribute substantially to overall biodiversity of a region, often contain unique elements of biodiversity, and can potentially be indicative of the ecological status of subterranean ecosystems that are providing important ecosystem services such as drinking water. Past research on subterranean organisms has often used highly specialised sampling techniques and expert knowledge. Here, we show that inclusion of non-professionals can be an alternative and highly promising sampling strategy. We retrieved citizen science-based samples from municipal groundwater wells across Switzerland, mainly from the Swiss Plateau. Opportunistic samples from 313 sites revealed a previously undocumented groundwater fauna including organisms from different major invertebrate groups, with a dominance of crustaceans. Here, we studied amphipods of the genus Niphargus. Among all 363 individuals sampled, we found in total eight nominal species. Two of them, namely N. fontanus and N. kieferi, are reported for Switzerland for the first time. We also found four further phylogenetic lineages that are potentially new species to science. One of them is here formally described as Niphargus arolaensissp. nov. The description is based on molecular and morphometric data. Our study proves the suitability of citizen science to document subterranean diversity, supports groundwater conservation efforts with data, and raises awareness for the relevance and biodiversity of groundwater amphipods among stakeholders.

Five new species are described, Plusiocampa (Didymocampa) cvijici Sendra & Antić, sp. nov., Plusiocampa (Plusiocampa) atom Sendra & Antić, sp. nov., Plusiocampa (Stygiocampa) barethae Sendra & Rađa, sp. nov., Plusiocampa (Stygiocampa) dulcici Sendra & Rađa, sp. nov. and Plusiocampa (Venetocampa) pirnati Sendra & Borko, sp. nov. This brings the number of cave-adapted species of campodeids known from the Dinarides, Eastern Alps, Balkan System and Rodope Massif to 28 (one species in the genus Campodea and 27 in Plusiocampa). Among Plusiocampa, four out of five subgenera are present (Pentachaetocampa is not present in the region studied): Didymocampa (one species), Plusiocampa s. str. (15 species), Stygiocampa (eight species) and Venetocampa (three species), whereby Stygiocampa and Venetocampa are endemic to the studied region. These results reveal the importance of the Dinarides karst region as a centre of diversification for campodeids and for cave animals in general. A monophyletic subgroup, consisting of Stygiocampa, Venetocampa and Plusiocampa s. str. and characterized by the absence of medial posterior thoracic macrosetae, presumably colonized the Dinaric plate during the middle of the Cenozoic and occurs in that area since then.

We characterized taxonomically, ecologically, and phylogenetically the amphipod community of Melissotrypa Cave (Central Greece), which comprises both freshwater and sulphidic lakes. We found four amphipod species: Niphargus jovanovici, Niphargus lindbergi, Niphargus gammariformis sp. nov. and an unknown species of Bogidiella. The three Niphargus species form a well-supported monophylum but differ in their ecology and morphology: N. jovanovici is a small and slender species inhabiting small freshwater voids, N. lindbergi is a large and stout species living in freshwater lakes, whereas N. gammariformis sp. nov. is a small and stout species found predominantly in a sulphidic lake. Available evidence suggests that diversification may have happened in a geographically restricted area and was driven by ecological differentiation. Niphargus gammariformis sp. nov. shows morphological convergences in diagnostic traits with two species hitherto classified into the genus Pontoniphargus. As molecular phylogenies show Pontoniphargus nested within Niphargus, we synonymize here Pontoniphargus with Niphargus. The species originally named Pontoniphargus ruffoi needed to be renamed into Niphargus pontoruffoi.http://www.zoobank.org/urn:lsid:zoobank.org:pub:4F5EED3B-DEB4-4402-BCE8-6AE2B65CCC3A., info:eu-repo/semantics/published

Adaptive radiations are bursts of evolutionary species diversification that have contributed to much of the species diversity on Earth. An exception is modern Europe, where descendants of ancient adaptive radiations went extinct, and extant adaptive radiations are small, recent and narrowly confined. However, not all legacy of old radiations has been lost. Subterranean environments, which are dark and food-deprived, yet buffered from climate change, have preserved ancient lineages. Here we provide evidence of an entirely subterranean adaptive radiation of the amphipod genus Niphargus, counting hundreds of species. Our modelling of lineage diversification and evolution of morphological and ecological traits using a time-calibrated multilocus phylogeny suggests a major adaptive radiation, comprised of multiple subordinate adaptive radiations. Their spatio-temporal origin coincides with the uplift of carbonate massifs in South-Eastern Europe 15 million years ago. Emerging subterranean environments likely provided unoccupied, predator-free space, constituting ecological opportunity, a key trigger of adaptive radiation. This discovery sheds new light on the biodiversity of Europe., There are relatively few known extant adaptive radiations in Europe that predate the Pleistocene. Here, Borko et al. characterize the diversity and diversification of the subterranean amphipod genus Niphargus, showing evidence for a large adaptive radiation associated with massif uplift 15 million years ago.

Este artículo contiene 138 páginas, 213 figuras, 14 tablas., Diplura is a group of entognathous hexapods, often considered a sister group to insects. They play an important role in recycling organic matter in soil and subterranean terrestrial ecosystems. The Campodeidae is the most diverse family, divided into four subfamilies. The subfamily Plusiocampinae has a subterranean life-style with many species distributed in the Euro-Mediterranean area. The incertae sedis tachycampoids (“lignée Tachycampoïde”) is a group within the family Campodeidae that share with the Plusiocampinae a strong preference for subterranean habitats and several morphological characters, such as slender body shape, elongated appendages, considerable increment in the number of antennomeres and cercal articles, and complexity of sensorial structures. The present monograph provides a taxonomic revision of the subfamily Plusiocampinae and the genera belonging to the tachycampoid lineage from Europe and the Mediterranean region. It comprises detailed morphological descriptions and illustrations together with data on the habitats and distributions of 87 species, 10 subspecies and 11 affinis forms. Seven new species are described among those, namely: Plusiocampa (Plusiocampa) apollo Sendra, Giachino & Vailati sp. nov., P. (P.) chiosensis Sendra & Gasparo sp. nov., P. (P.) dublanskii Sendra & Turbanov sp. nov., P. (P.) hoffmanni Sendra & Paragamian sp. nov., P. (P.) rhea Sendra sp. nov., P. (P.) ternovensis Sendra & Borko sp. nov. and P. (Venetocampa) ferrani Sendra & Delić sp. nov., DS’s field trips were funded by the Serbian Ministry of Education, Science and Technology (Grant 173038); KP was partially funded by the HISR project “Conservation of the Cave Fauna of Greece” funded by the MAVA Foundation and WWF Greece; PMG and DV carried out sampling in Greece using permits from the Ministry of Environment no. 124085/1362/2015, 135366/373/2016 and 166238/248/2018; IT was funded within the framework of the state assignment of FASO Russia (themes no. АААА-А18-118012690106-7 and АААА-А18-118012690105), supported in part by RFBR (project no. 17-54-40017Абх_а); sampling efforts by AF and colleagues resulted from various projects on the evolution of cave fauna diversity, some of them funded by the German Research Foundation, DFG (DFG FA 1042/1-1 and DFG BA 2152/14-1); PMG and DV were partly supported by the program “Research Missions in the Mediterranean Basin” sponsored by the World Biodiversity Association onlus XLI contribution; ASPSR was supported by a research grant (15471) from Villum Fonden.

Terrestrial life typically does not occur at depths greater than a few meters. Notable exceptions are massifs of fissured rock with caves and hollow spaces reaching depths of two kilometres and more. Recent biological discoveries from extremely deep caves have been reported as sensations analogous to wondrous deep sea creatures. However, the existence of unique deep terrestrial communities is questionable when caves are understood as integral parts of a bedrock fissure network (BFN) interconnecting all parts of a massif horizontally and vertically. We tested these two opposing hypotheses – unique deep cave fauna vs. BFN – by sampling subterranean communities within the 3D matrix of a typical karst massif. There was no distinction between deep core and shallow upper zone communities. Beta diversity patterns analysed against null models of random distribution were generally congruent with the BFN hypothesis, but suggested gravity-assisted concentration of fauna in deep caves and temperature-dependent horizontal distribution. We propose that the idea of a unique deep terrestrial fauna akin to deep oceanic life is unsupported by data and unwarranted by ecological considerations. Instead, the BFN hypothesis and local ecological and structural factors sufficiently explain the distribution of subterranean terrestrial life even in the deepest karst massifs.

The ecological radiation of amphipods is striking among crustaceans. Despite high diversity, global distribution and key roles in all aquatic environments, little is known about their ecological transitions, evolutionary timescale and phylogenetic relationships. It has been proposed that the amphipod ecological diversification began in the Late Palaeozoic. By contrast, due to their affinity for cold/oxygenated water and absence of pre-Cenozoic fossils, we hypothesized that the ecological divergence of amphipods arose throughout the cool Late Mesozoic/Cenozoic. We tested our hypothesis by inferring a large-scale, time-calibrated, multilocus phylogeny, and reconstructed evolutionary patterns for major ecological traits. Although our results reveal a Late Palaeozoic amphipod origin, diversification and ecological divergence ensued only in the Late Mesozoic, overcoming a protracted stasis in marine littoral habitats. Multiple independent post-Jurassic radiations took place in deep-sea, freshwater, terrestrial, pelagic and symbiotic environments, usually postdating deep-sea faunal extinctions, and corresponding with significant climatic cooling, tectonic reconfiguration, continental flooding, and increased oceanic oxygenation. We conclude that the profound Late Mesozoic global changes triggered a tipping point in amphipod evolution by unlocking ecological opportunities that promoted radiation into many new niches. Our study also provides a solid, time-calibrated, evolutionary framework to accelerate research on this overlooked, yet globally important taxon.

The amphipod genus Niphargus (Amphipoda: Niphargidae Bousfield, 1977) is the most species-rich genus of freshwater amphipods in the World. Species of this genus, which live almost exclusively in subterranean water, offer an interesting model system for basic and applied biodiversity science. Their use, however, is often limited due to the hitherto unresolved taxonomy within the whole genus. As a comprehensive taxonomic revision of the currently >425 Niphargus species is too demanding, it has been suggested that the taxonomy of the genus could be advanced in smaller steps, by reviewing regional faunas, that would eventually integrate into a global revision. In this study, we provide such a revision of Niphargus in Switzerland. First, we molecularly delimited, morphologically diagnosed, and formally described two new species, namely Niphargus luchoffmanni sp. n. and Niphargus tonywhitteni sp. n. Second, we updated and revised a checklist of Niphargus in Switzerland with new findings, and prepared a list of reference sequences for routine molecular identification, available at BOLD and GenBank. All available specimens of 22 known species from the area were morphologically examined, and their morphological variation was compiled in a data file of DEscription Language for TAxonomy, which can be used for automated generation of dichotomous or interactive keys. The data file is freely available at the World Amphipoda Database. Together, the checklist, the library of reference sequences, the DELTA file, but also a list of hitherto unresolved aspects are an important step towards a complete revision of the genus within a well-defined and biogeographically interesting area in Central Europe.

The amphipod genusNiphargus(Amphipoda: Niphargidae Bousfield, 1977) is the most species-rich genus of freshwater amphipods in the World. Species of this genus, which live almost exclusively in subterranean water, offer an interesting model system for basic and applied biodiversity science. Their use, however, is often limited due to the hitherto unresolved taxonomy within the whole genus. As a comprehensive taxonomic revision of the currently >425Niphargusspecies is too demanding, it has been suggested that the taxonomy of the genus could be advanced in smaller steps, by reviewing regional faunas, that would eventually integrate into a global revision. In this study, we provide such a revision ofNiphargusin Switzerland. First, we molecularly delimited, morphologically diagnosed, and formally described two new species, namelyNiphargusluchoffmannisp. n.andNiphargustonywhittenisp. n.Second, we updated and revised a checklist ofNiphargusin Switzerland with new findings, and prepared a list of reference sequences for routine molecular identification, available at BOLD and GenBank. All available specimens of 22 known species from the area were morphologically examined, and their morphological variation was compiled in a data file of DEscription Language for TAxonomy, which can be used for automated generation of dichotomous or interactive keys. The data file is freely available at the World Amphipoda Database. Together, the checklist, the library of reference sequences, the DELTA file, but also a list of hitherto unresolved aspects are an important step towards a complete revision of the genus within a well-defined and biogeographically interesting area in Central Europe.