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The development of molecular techniques as a taxonomic tool and their integration with information provided by other disciplines, has enhanced species discovery, facilitated species delimitation and produced invaluable data for inferring species phylogenies. Here, we provide an example of how DNA sequence data, together with morphometric, distributional and ecological information, assist in identifying and diagnosing previously overlooked lineages. The nocturnal, ground-dwelling spider genus Dysdera has colonized all the Macaronesian archipelagos, and has undergone a major diversification in the Canary Islands. A recent molecular phylogenetic analysis of Dysdera species from the eastern Canary Islands revealed deep genetic divergences among some populations, suggesting the existence of cryptic taxa. Here, we combine data from mitochondrial and nuclear loci with morphological and ecological evidence to delimit and formally describe three previously overlooked species: D. aneris sp. nov., endemic to the Salvage Islands; D. mahan sp. nov., distributed along coastal habitats of Lanzarote, north of Fuerteventura and adjacent islets; and D. simbeque sp. nov., restricted to two valleys in northern Lanzarote. Molecular markers provide key information that allows apparent morphological polymorphisms to be used as diagnostic features of evolutionarily independent lineages. Dysdera mahan sp. nov. is unique among the Canarian Dysdera in that it is found in the intertidal zone on pebbled beaches. Low levels of genetic variability and genital differentiation associated with relatively high somatic divergence suggest that speciation in D. mahan sp. nov. was driven by a selection of phenotypic traits that are adaptive to this rare environment. Separate analyses and statistical tests revealed phylogenetic incongruence between mitochondrial and nuclear genes, probably as a result of incomplete lineage sorting. The temporal framework for the origin and diversification of the new species inferred from the molecular data corroborates former hypotheses on the late Pliocene origin of the present-day biota of the Salvage Islands. [ABSTRACT FROM AUTHOR]

We investigated the phylogenetic patterns, evolutionary processes, and their taxonomic implications, of two closely related shield-backed katydid genera endemic to the Macaronesian archipelagos: the monotypic Psalmatophanes Chopard, 1938 endemic to Madeira and Calliphona Krauss, 1892, which includes three species restricted to the Canary Islands. Two main hypotheses have been proposed to explain the origin and colonization pathways of these two genera: a single origin with subsequent sequential colonization of the islands, or three independent colonization waves from continental Africa. We used DNA sequence information from the mitochondrial genes cox1, tRNAleucine, rrnL and nad1 to infer phylogenetic relationships among Psalmatophanes and Calliphona species. Our results provide support for the independent colonization of Madeira and the Canary Islands, and suggest that Psalmatophanes is actually more closely related to the continental genus Tettigonia than to the Canarian representatives. Deep genetic divergence among Canarian species provides further support for the assignment of the Canarian species into two subgenera. Tree topology along with Bayesian-based estimates of lineage age suggest a pattern of colonization from Tenerife to La Palma, and from Tenerife to Gran Canaria with subsequent dispersal to La Gomera. We report the first collection of a Calliphona specimen in the island of El Hierro, which molecular data suggest is a recent immigrant from La Gomera. We hypothesize that the patterns of distribution and genetic divergence exhibited by Calliphona in the Canary Islands are compatible with a taxon cycle process. Our results have further implications for the higher level phylogeny of the subfamily Tettigoniinae and suggest that some of the tribes as currently delimited may not correspond to natural groups. [ABSTRACT FROM AUTHOR]

The flightless beetle genus Tarphius Erichson (Coleoptera: Colydiidae) is a distinctive element of the beetle fauna of the Canary Islands with 29 species distributed across the five western islands. The majority of Tarphius species are rare and intimately associated with the monteverde forest and only two species occur on more than one island. In this study we investigate the phylogeography of the Canary Island Tarphius, and their relationship to Tarphius from the more northerly archipelagos of Madeira and the Azores using maximum parsimony and Bayesian inference analysis of mitochondrial cytochrome oxidase I and II sequence data. We use geological datings for the Canary Islands, Azores, and Madeira to calibrate specific nodes of the tree for the estimation of divergence times using a penalized likelihood method. Data suggest that the Canary Island species assemblage is of some antiquity, however, much of this species diversity is relatively recent in origin. The phylogenetic relationships of species inhabiting the younger islands of El Hierro and La Palma indicate that colonization events between islands have probably been a significant factor in the evolutionary history of the Canary Island species assemblage. A comparison of molecular phylogenetic studies of arthropods on the Canary Islands suggests that, in the evolution of the arthropod species community of an island, the origin of endemic species is initially the result of colonizing lineages differentiating from their source populations. However, as an island matures a greater proportion of endemic species originate from intra-island speciation. [ABSTRACT FROM AUTHOR]

Cueva del Viento and Cueva de Felipe Reventón are lava tubes located in Tenerife, Canary Islands, and are considered the volcanic caves with the greatest cave-dwelling diversity in the world. Geological aspects of the island relevant to the formation of these caves are discussed, and their most outstanding internal geomorphological structures are described. An analysis of the environmental parameters relevant to animal communities is made, and an updated list of the cave-adapted species and their way of life into the caves is provided. Some paleontological data and comments on the conservation status of these tubes are included. [ABSTRACT FROM AUTHOR]

Heriaeus buffoni (Audouin, 1826) is reported for the first time from the Canary Islands, where it was found on Lanzarote. This also represents the first record of the genus in the archipelago. All individuals were collected with pitfall traps installed in nitrophilous synanthropic shrub vegetation near urban areas. Species identification was based on male genitalia only as females were not sampled. A map including all known records from Lanzarote, drawings of the pedipalps and photographs of living and preserved specimens are presented. [ABSTRACT FROM AUTHOR]

We describe the hitherto unknown male of Centromerus fuerteventurensis Wunderlich, 1992 and present new illustrations of the epigyne and vulva. We also provide an update on the known distribution of this species on the Canary Islands. [ABSTRACT FROM AUTHOR]

The genus Baezia Alonso-Zarazaga & García, 1999 is endemic to the Canary Islands, where four species were known to date. Based on morphological evidence, three new species of Baezia are described in this study: Baezia aranfaybo García & López, sp. nov. from El Hierro island, and Baezia madai García & Oromí sp. nov. and Baezia tizziri García & Andújar, sp. nov. from La Palma island. Notes on their biology, habitat, and distribution are presented. The number of taxa in this endemic Canarian genus increases to seven eyeless species. One species has been reported from the soil (endogean environment), with the other six associated with caves and the mesovoid shallow substratum (hypogean or subterranean environment). Frequent association with the presence of roots suggests that species of Baezia may inhabit the continuum represented by the endogean and hypogean environments. Identification key to the seven species are provided. [ABSTRACT FROM AUTHOR]

A new blind weevil belonging to the genus Oromia Alonso-Zarazaga, 1987 is described, being found in the underground of the laurel forest of La Gomera (Canary Islands). Individuals were mainly collected in a colluvial mesocavernous shallow substratum, besides one specimen collected in the deep humic layer of soil. This new species has clear diagnostic differences from the other Oromia species. The number of taxa in this endemic Canarian genus increases to four species, easily identified using the key provided in this article. New data on other Canarian subterranean weevils are also provided. [ABSTRACT FROM AUTHOR]

[Display omitted] • Decomposition was studied at surface and in caves along an elevational gradient. • Overall decomposition levels were comparable in above and below ground habitats. • At the surface abiotic and biotic factors correlate only with decomposition rate. • In caves abiotic and biotic parameters are associated with stabilizing factor. • Current predictions underestimate the net carbon budget in areas with caves. Decomposition is a major contributor to ecosystem respiration, determining the carbon emission and nutrient cycling rates. Our current understanding of decomposition dynamics and their underlying drivers has mainly focused on surface habitats but largely ignored in subterranean environments. Here we studied abiotic and microbial drivers of early-stage litter decomposition inside and outside caves along an elevational gradient in Tenerife. We found comparable decomposition rates (k) and litter stabilizing factors (S), with contrasting drivers and elevational variation. At the surface, we observed a mid-elevational trend in k , which tended to correlate with water availability, cooler temperatures, nutrient availability, and surface-specific bacterial taxa. In sharp contrast, caves showed no elevational impact nor influence of abiotic parameters and bacterial communities on k. Despite this, we found higher levels of S in caves, which were associated mainly with reduced water availability, lower temperatures and cave-specific bacterial taxa, indicating that conditions in caves are strongly linked with carbon storage. Our findings imply that our current perception of terrestrial habitat-based carbon cycling are underestimating the net carbon budget in areas with caves. Disentangling the role of the environment on decomposition in caves is key to fully characterize their roles in nutrient cycling and to understand how increasing anthropogenic pressures will affect fundamental processes in subterranean ecosystems. [ABSTRACT FROM AUTHOR]

Climate change affects all ecosystems, but subterranean ecosystems are repeatedly neglected from political and public agendas. Cave habitats are home to unknown and endangered species, with low trait variability and intrinsic vulnerability to recover from human-induced disturbances. We studied the annual variability and cyclicity of temperatures in caves vis-à-vis surface in different climatic areas. We hypothesize that cave temperatures follow the average temperature pattern at the surface for each location with a slight delay in the signal, but we found three different thermal patterns occurring in caves: (1) high positive correlation and a similar thermal pattern to the surface, (2) low correlation and a slight thermal delay of the signal from the surface, and (3) high negative correlation with an extreme delay from the surface. We found daily thermal cycles in some caves, which may potentially control the circadian rhythms of cave organisms. Our results show that caves had lower thermal amplitude than the surface, and that thermal averages within caves approximately correspond to the to the annual average of surface temperature. Caves buffer external temperature and act as refugia for biota in extreme climatic events. Likewise, temperature increases at surface will lead to increment in caves, threatening subterranean biota and ecosystem services. [ABSTRACT FROM AUTHOR]

The genus Barretonus Roudier, 1958 is a genus endemic to Macaronesia, described from the archipelago of Madeira where four species are known to date. In this study, two new species of Barretonus, B. auarita García & Oromí sp. nov. (from La Palma, Canary Islands) and B. daute García & Andújar sp. nov. (from Tenerife, Canary Islands), are described based on morphological and molecular evidence (mtCOI), and additional notes on their biology and ecology are provided. Morphology of the new species is compared with the other representatives of the genus, and their phylogenetic relationships with a Barretonus representative from Madeira and species from additional genera within the Cossoninae are shown. This work increases the number of species of the genus Barretonus from four to six anophthalmous or microphthalmous species with an endogean lifestyle, and incorporates the Canary Islands into its Macaronesian range of distribution. [ABSTRACT FROM AUTHOR]

The amphi-Atlantic distributions exhibited by many thalassoid stygobiont (obligate subterranean) crustaceans have been explained by fragmentation by plate tectonics of ancestral shallow water marine populations. The amphipod stygobiont genus Pseudoniphargus is distributed across the Mediterranean region but also in the North Atlantic archipelagos of Bermuda, Azores, Madeira and the Canaries. We used species delimitation methods and mitogenome phylogenetic analyses to clarify the species diversity and evolutionary relationships within the genus and timing their diversification. Analyses included samples from the Iberian Peninsula, northern Morocco, the Balearic, Canarian, Azores and Madeira archipelagoes plus Bermuda. In most instances, morphological and molecular-based species delimitation analyses yielded consistent results. Notwithstanding, in a few cases either incipient speciation with no involvement of detectable morphological divergence or species crypticism were the most plausible explanations for the disagreement found between morphological and molecular species delimitations. Phylogenetic analyses based on a robust calibrated mitochondrial tree suggested that Pseudoniphargus lineages have a younger age than for other thalassoid amphipods displaying a disjunct distribution embracing both sides of the Atlantic Ocean. A major split within the family was estimated to occur at the Paleocene, when a lineage from Northern Iberian Peninsula diverged from the rest of pseudoniphargids. Species diversification in the peri-Mediterranean area was deduced to occur in early Miocene to Tortonian times, while in the Atlantic islands it started in the Pliocene. Our results show that the current distribution pattern of Pseudoniphargus resulted from a complex admix of relatively ancient vicariance events and several episodes of long- distance dispersal. [ABSTRACT FROM AUTHOR]

Most of our understanding of island diversity comes from the study of aboveground systems, while the patterns and processes of diversification and community assembly for belowground biotas remain poorly understood. Here, we take advantage of a relatively young and dynamic oceanic island to advance our understanding of ecoevolutionary processes driving community assembly within soil mesofauna. Using whole organism community DNA (wocDNA) metabarcoding and the recently developed metaMATE pipeline, we have generated spatially explicit and reliable haplotype‐level DNA sequence data for soil mesofaunal assemblages sampled across the four main habitats within the island of Tenerife. Community ecological and metaphylogeographic analyses have been performed at multiple levels of genetic similarity, from haplotypes to species and supraspecific groupings. Broadly consistent patterns of local‐scale species richness across different insular habitats have been found, whereas local insular richness is lower than in continental settings. Our results reveal an important role for niche conservatism as a driver of insular community assembly of soil mesofauna, with only limited evidence for habitat shifts promoting diversification. Furthermore, support is found for a fundamental role of habitat in the assembly of soil mesofauna, where habitat specialism is mainly due to colonization and the establishment of preadapted species. Hierarchical patterns of distance decay at the community level and metaphylogeographical analyses support a pattern of geographic structuring over limited spatial scales, from the level of haplotypes through to species and lineages, as expected for taxa with strong dispersal limitations. Our results demonstrate the potential for wocDNA metabarcoding to advance our understanding of biodiversity. [ABSTRACT FROM AUTHOR]

Comparative phylogeography seeks for commonalities in the spatial demographic history of sympatric organisms to characterize the mechanisms that shaped such patterns. The unveiling of incongruent phylogeographic patterns in co-occurring species, on the other hand, may hint to overlooked differences in their life histories or microhabitat preferences. The woodlouse-hunter spiders of the genus Dysdera have undergone a major diversification on the Canary Islands. The species pair Dysdera alegranzaensis and Dysdera nesiotes are endemic to the island of Lanzarote and nearby islets, where they co-occur at most of their known localities. The two species stand in sharp contrast to other sympatric endemic Dysdera in showing no evidence of somatic (non-genitalic) differentiation. Phylogenetic and population genetic analyses of mitochondrial cox1 sequences from an exhaustive sample of D. alegranzaensis and D. nesiotes specimens, and additional mitochondrial ( 16S , L1, nad1) and nuclear genes ( 28S, H3) were analysed to reveal their phylogeographic patterns and clarify their phylogenetic relationships. Relaxed molecular clock models using five calibration points were further used to estimate divergence times between species and populations. Striking differences in phylogeography and population structure between the two species were observed. Dysdera nesiotes displayed a metapopulation-like structure, while D. alegranzaensis was characterized by a weaker geographical structure but greater genetic divergences among its main haplotype lineages, suggesting more complex population dynamics. Our study confirms that co-distributed sibling species may exhibit contrasting phylogeographic patterns in the absence of somatic differentiation. Further ecological studies, however, will be necessary to clarify whether the contrasting phylogeographies may hint at an overlooked niche partitioning between the two species. In addition, further comparisons with available phylogeographic data of other eastern Canarian Dysdera endemics confirm the key role of lava flows in structuring local populations in oceanic islands and identify localities that acted as refugia during volcanic eruptions. [ABSTRACT FROM AUTHOR]

A bibliographic analysis of the hypogean biological studies in Portugal is made, compiling 138 publications related to the subterranean invertebrate fauna, since its begining in 1870 until November 2012. A catalogue of hypogean endemic taxa is provided, listing 27 troglobionts and 63 stygobionts, described to be obligate hypogean and endemic from mainland Portugal (Macaronesian archipelagos excluded). The first impetus on troglobiont studies was provided by the prospections of Barros Machado during 1940's and by an expedition of Lindberg in the spring of 1961; and the major information about stygobiont species was provided by the former Instituto de Zoologia "Dr. Augusto Nobre" from Porto University. [ABSTRACT FROM AUTHOR]

Meenoplus roddenberryi sp.n., an obligate cavernicolous and highly troglomorphic meenoplid species, is described from an artificial cave on Gran Canaria. Notes on its ecology are given. A key to the cave-dwelling Meenoplidae of the Canary Islands is provided. As Meenoplidae are not part of the present-day epigean fauna of the Canary Islands, the occurrence of cavernicolous species provides testimony of an ancient fauna which is now extinct. Despite their current relict status, it remains equivocal whether evolution of cave Meenoplidae was driven by allopatric speciation, or whether an adaptive shift to exploit a novel food resource triggered the colonization of caves. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Within the soil matrix and underlying rock, cracks and fissures and other air-filled spaces between rocks, sometimes called the milieu souterrain superficiel (MSS), are present in a variety of geological contexts. We examined year-long hourly temperature profiles at sites in lava in the Canary Islands and limestone in Slovenia. All sites had species that show morphological adaptations usually associated with cave-dwelling organisms, including elongated appendages and reduced eyes and pigment. MSS sites were studied at depths between 10 and 70 cm and showed strong seasonality, and most had a discernible diurnal cycle as well. The most striking difference from surface habitats was that the temperature extremes were much less pronounced in MSS sites. Temperature variability was not correlated with troglobiotic species richness. The presence of species with similar morphologies to those found in caves indicates that selective pressures are similar in cave and shallow subterranean habitats. [ABSTRACT FROM AUTHOR]

Background: The amphipod crustacean Palmorchestia hypogaea occurs only in La Palma (Canary Islands) and is one of the few terrestrial amphipods in the world that have adapted to a strictly troglobitic life in volcanic cave habitats. A surface-dwelling closely related species (Palmorchestia epigaea) lives in the humid laurel forest on the same island. Previous studies have suggested that an ancestral littoral Orchestia species colonized the humid forests of La Palma and that subsequent drought episodes in the Canaries reduced the distribution of P. epigaea favouring the colonization of lava tubes through an adaptive shift. This was followed by dispersal via the hypogean crevicular system. Results: P. hypogaea and P. epigaea did not form reciprocally monophyletic mitochondrial DNA clades. They showed geographically highly structured and genetically divergent populations with current gene flow limited to geographically close surface locations. Coalescence times using Bayesian estimations assuming a non-correlated relaxed clock with a normal prior distribution of the age of La Palma, together with the lack of association of habitat type with ancestral and recent haplotypes, suggest that their adaptation to cave life is relatively ancient. Conclusion: The data gathered here provide evidence for multiple invasions of the volcanic cave systems that have acted as refuges. A re-evaluation of the taxonomic status of the extant species of Palmorchestia is needed, as the division of the two species by habitat and ecology is unnatural. The information obtained here, and that from previous studies on hypogean fauna, shows the importance of factors such as the uncoupling of morphological and genetic evolution, the role of climatic change and regressive evolution as key processes in leading to subterranean biodiversity. [ABSTRACT FROM AUTHOR]

The Eastern Canary Islands are the emerged tips of a continuous volcanic ridge running parallel to the northeastern African coast, originated by episodic volcanic eruptions that can be traced back to the Miocene and that, following a major period of quiescence and erosion, continued from the Pliocene to the present day. The islands have been periodically connected by eustatic sea-level changes resulting from Pleistocene glacial cycles. The ground-dwelling spider Dysdera lancerotensis Simon, 1907 occurs along the entire ridge, except on recent barren lavas and sand dunes, and is therefore an ideal model for studying the effect of episodic geological processes on terrestrial organisms. Nested clade and population genetic analyses using 39 haplotypes from 605 base pairs of mitochondrial DNA cytochrome c oxidase I sequence data, along with phylogenetic analyses including two additional mitochondrial genes, uncover complex phylogeographical and demographic patterns. Our results indicate that D. lancerotensis colonized the ridge from north to south, in contrast to what had been expected given the SSW-NNE trend of volcanism and to what had been reported for other terrestrial arthropods. The occurrence of several episodes of extinction, recolonization and expansion are hypothesized for this species, and areas that act as refugia during volcanic cycles are identified. Relaxed molecular clock methods reveal divergence times between main haplotype lineages that suggest an older origin of the northern islets than anticipated based on geological evidence. This study supports the key role of volcanism in shaping the distribution of terrestrial organisms on oceanic islands and generates phylogeographical predictions that warrant further research into other terrestrial endemisms of this fascinating region. [ABSTRACT FROM AUTHOR]

Abstract: The beetle genus Trechus (Carabidae) is represented in the Macaronesian Islands by 43 endemic species. The Canary Islands have 16 endemic species, with two adapted to hypogean life. Phylogenetic relationships among 177 individuals of 38 Canarian, Madeiran, Azorean and continental Trechus species were examined using mitochondrial DNA and nuclear internal transcribed spacer 2 (ITS2) sequence data. Results show two main lineages in the Canaries: one comprising two sister groups with species from the laurel forest of La Gomera and Tenerife, and the other containing the single species from Gran Canaria and a species complex in the four western islands including two troglobites. Calibrations were applied to a linearized tree using a relaxed molecular clock method to estimate the major evolutionary divergence times of the Canarian Trechus species. Although the species assemblage in this archipelago is relatively ancient (7–8 million years), much of the species diversity is recent. Transition to the hypogean environment is more consistent with the “adaptive shift” rather than with the competing “climatic relict” hypothesis. [Copyright &y& Elsevier]

The volcanic island of Tenerife (Canary archipelago) was formerly covered at 600–1200 m above sea level on most of its northern side by a cloud forest holding much of the endemic insect fauna. In the most significant surviving patches of this laurel forest at the eastern and western tips of the island occur two forest-specialist, closely related species of Eutrichopus (Coleoptera, Carabidae); here we present data on mitochondrial DNA variation among populations of these species. In total, 116 individuals from 16 localities were sampled and a 638 bp fragment of the cytochrome oxidase subunit 11 gene was sequenced, obtaining evidence for two distinct evolutionary lineages, in accordance with morphological and biogeographical data. Volcanic events at ∼0.7 Ma might be responsible for vicariance and the fragmentation of the geographical range of an ancestral species, causing the establishment of two matrilineal lineages. Using nested clade and historical demography analyses we infer past cycles of demographic bottlenecks followed by population expansion, mostly in agreement with the geological timescale of volcanic events. Recent trends, however, refer to fragmentation of the cloud forest due to human intervention. [ABSTRACT FROM AUTHOR]

Aim: Habitat diversity has been linked to the diversity and structure of island communities, however, little is known about patterns and processes within habitats. Here we aim to determine the contributions of habitat type and inferred dispersal frequency to the differences in taxonomic structure between assemblages in the same island habitat. Location: The Macaronesian archipelagos (Azores, Madeira, the Canary Islands and Cabo Verde). Taxon: Spiders (Araneae). Methods: We established forest and dry habitat sites (each with five plots) on two islands per archipelago. We collected spiders using standardised sampling protocols. We tested the differences in beta diversity separately for each habitat and for each inferred category of ballooning (an aerial dispersal strategy) frequency across geographic scales through nested non-parametric permutational multivariate analyses of variance. We then tested whether ballooning and habitat influenced heterogeneity in species composition (dispersion in beta diversity) in the two habitat types. We analysed the effects of habitat and ballooning on species abundance distribution (SAD) and rarity by fitting Gambin models and evaluating the contribution of ballooning categories to SAD. Results: Communities of the same archipelago and habitat were taxonomically more similar, and beta diversity increased with geographic scale, being greater in dry habitats. There was greater species replacement among assemblages in dry habitats than in forests, with greater differences for rare ballooners. There were no differences in SAD between habitats although dry habitat sites seemed to harbour more species with low abundances (rare species) than forests. Main conclusions: Habitat type does not only condition the differences between spider assemblages of the same habitat but also the scale at which they occur. These differences may be determined by the heterogeneity in the physical structure of each habitat as well as how much this structure facilitates aerial dispersal (ballooning), and should be considered in theories/hypotheses on island community assembly as well as in conservation strategies. [ABSTRACT FROM AUTHOR]

Two new dipluran species of the family Campodeidae have been unearthed in the Canary Islands. Remycampa herbanica sp. nov. was found in a highly threatened lava tube on Fuerteventura island. It is related to the soil-dwelling northwest African Remycampa launeyi that also inhabits four of the Canary Islands. The two known Remycampa species are characterized by a torsion of the labial palps. They differ chiefly in the distribution of macrosetae and in the features of cave adaptation of R. herbanica, i.e. elongation of body and appendages, and a higher number of olfactory chemoreceptors with a coniform shape unique within campodeids. Spaniocampa relicta sp. nov. was collected in the mesovoid shallow substratum (MSS) and has been assigned to a formerly monotypic genus that includes the soil-dwelling Spaniocampa prima from the Republic of Guinea. The two species differ in the number of abdominal macrosetae. Females of S. relicta sp. nov. have small setae arranged in groups along the posterior border of the first urosternite. These structures of unknown function have never been described in other campodeid species. Sequencing the COI barcode region of R. herbanica has been produced but it proved insufficient to identify closest relatives. The two new hexapods from subterranean habitats raise the Canarian campodeid fauna to six species. Five of them are living in soil and/or MSS, whereas the cave-adapted R. herbanica is known only from a single, particularly endangered lava tube distant from other caves. [ABSTRACT FROM AUTHOR]

Geographic isolation substantially contributes to species endemism on oceanic islands when speciation involves the colonisation of a new island. However, less is understood about the drivers of speciation within islands. What is lacking is a general understanding of the geographic scale of gene flow limitation within islands, and thus the spatial scale and drivers of geographical speciation within insular contexts. Using a community of beetle species, we show that when dispersal ability and climate tolerance are restricted, microclimatic variation over distances of only a few kilometres can maintain strong geographic isolation extending back several millions of years. Further to this, we demonstrate congruent diversification with gene flow across species, mediated by Quaternary climate oscillations that have facilitated a dynamic of isolation and secondary contact. The unprecedented scale of parallel species responses to a common environmental driver for evolutionary change has profound consequences for understanding past and future species responses to climate variation. [ABSTRACT FROM AUTHOR]

New data concerning the distribution about nine Coleoptera and five Diptera species are given. Lema bilineata Germar, 1823 (Coleoptera: Chrysomelidae), Olla v-nigrum (Mulsant, 1866) (Coleoptera: Coccinellidae) and Sphaeridium marginatum Fabricius, 1787 (Coleoptera: Hydrophilidae) are reported for the first time for the archipelago. [ABSTRACT FROM AUTHOR]

Aim The majority of documented extinctions world-wide in the last four centuries are of species endemic to islands. However, the phenomenon of delayed extinctions as a result of habitat loss has rarely been assessed on oceanic islands. In this study, we tested whether extinction debt ( ED), in general, occurs on islands and for which taxonomical groups this phenomenon is most pronounced by assessing ED for multiple endemic taxa and for each of the main altitudinal ecosystems in a well-studied oceanic archipelago. Location Canary Islands. Methods We characterized habitat preferences for all endemic species of several taxonomic groups (vascular plants, ground and darkling beetles, flies and land snails). Using generalized linear mixed models and available data about habitat distributions, we tested for all taxa and habitat types to determine whether past habitat area better explained current richness of habitat specialists than current habitat area. If so, an extinction debt can be assumed. Results For all five major habitat types and five taxonomic groups studied, present-day richness of habitat specialists fitted better with past than current habitat area, evidencing habitat- and taxon-specific extinction debts. This pattern was consistent for both long-lived vascular plants and short-lived invertebrates. Single island endemics in each taxonomic group showed steeper slopes of the species-area relationship ( SAR) compared to archipelago endemics indicating higher sensitivity to habitat loss which might increase sizes of ED. Conclusion Despite differences in species' generation times, plants and invertebrates showed delayed extinctions after habitat destruction in the Canary Islands. Our SAR approach suggests that a considerable number of Canary Island endemics will eventually become extinct in the future without further habitat loss. The case of the Canary archipelago is probably not unique. Hence, we interpret our results as a warning for island conservationists that the worst of the extinction crisis on oceanic islands might be yet to come. Conservation actions should focus on habitat restoration to attenuate or reverse current extinction processes. [ABSTRACT FROM AUTHOR]

Obtaining fundamental biodiversity metrics such as alpha, beta and gamma diversity for arthropods is often complicated by a lack of prior taxonomic information and/or taxonomic expertise, which can result in unreliable morphologically based estimates. We provide a set of standardized ecological and molecular sampling protocols that can be employed by researchers whose taxonomic skills may be limited, and where there may be a lack of robust a priori information regarding the regional pool of species. These protocols combine mass sampling of arthropods, classification of samples into parataxonomic units ( PUs) and selective sampling of individuals for mt DNA sequencing to infer biological species. We sampled ten lowland rainforest plots located on the volcanic oceanic island of Réunion (Mascarene archipelago) for spiders, a group with limited taxonomic and distributional data for this region. We classified adults and juveniles into PUs and then demonstrated the reconciliation of these units with presumed biological species using mt DNA sequence data, ecological data and distributional data. Because our species assignment protocol is not reliant upon prior taxonomic information, or taxonomic expertise, it minimizes the problem of the Linnean shortfall to yield diversity estimates that can be directly compared across independent studies. Field sampling can be extended to other arthropod groups and habitats by adapting our field sampling protocol accordingly. [ABSTRACT FROM AUTHOR]

Using a series of standardized sampling plots within forest ecosystems in remote oceanic islands, we reveal fundamental differences between the structuring of aboveground and belowground arthropod biodiversity that are likely due to large-scale species introductions by humans. Species of beetle and spider were sampled almost exclusively from single islands, while soil-dwelling Collembola exhibited more than tenfold higher species sharing among islands. Comparison of Collembola mitochondrial metagenomic data to a database of more than 80 000 Collembola barcode sequences revealed almost 30% of sampled island species are genetically identical, or near identical, to individuals sampled from often very distant geographic regions of the world. Patterns of mt DNA relatedness among Collembola implicate human-mediated species introductions, with minimum estimates for the proportion of introduced species on the sampled islands ranging from 45% to 88%. Our results call for more attention to soil mesofauna to understand the global extent and ecological consequences of species introductions. [ABSTRACT FROM AUTHOR]

The ground-dweller spider genus Dysdera shows very high species richness on the oceanic archipelago of the Canary Islands, providing one of the most outstanding examples of island radiation among spiders, only paralleled by Tetragnatha spiders on the Hawaiian archipelago. A georeferenced database of the 48 Dysdera species occurring in the Canary Islands was assembled to facilitate ongoing and future research on this remarkable lineage. All species are endemic to the archipelago except for the cosmopolitan Dysdera crocata. The dataset consists of 794 distributional records documented from 1971 to 2015, each locality being represented only once per species. Distribution maps are provided for each species, along with basic diversity and distribution information. The database and geographical maps included in this article stand for the most updated, accurate and complete information on the distribution of the spider genus Dysdera in the Canary Islands. [ABSTRACT FROM AUTHOR]

Aim To obtain nuclear and mitochondrial phylogenies of Macaronesian Rhopalomesites weevils and test the monophyly and time of origin of two species groups feeding on Euphorbiaceae and other plants. Additionally, to investigate the population structure within species, and its associations with geographical isolation versus trophic selection. Location Macaronesian Islands and the British Isles. Methods Maximum likelihood and Bayesian phylogenetic analyses were undertaken using mitochondrial ( cox1 and cytb) and nuclear ( ITS-2 and 28S RNA) genomic sequences. Ancestral Rhopalomesites host plant associations and divergence times were inferred from Bayesian analyses and population data. Results Evidence was found for two Rhopalomesites clades. One was associated with Euphorbia host plants, having vicariant species in the Madeira and Canary archipelagos. In this lineage, an ancestral association with Euphorbia mellifera in the two island groups was deduced, which has subsequently undergone shifts to related host plant species in marginal areas. The second clade was found to be an ecological generalist, exploiting decaying wood from the Lauraceae or other forest trees - is also present on such islands along with the Azores and parts of Atlantic Western Europe. Main conclusions The results point to a quasi-parallel colonization by the two ecologically distinct lineages in Macaronesia, dating to the early Pliocene, followed by allopatric isolation according to the presence of suitable habitats on particular islands in more recent times. [ABSTRACT FROM AUTHOR]

1. The large flightless grasshopper Acrostira bellamyi Uvarov, endemic to the island of La Gomera ( Canary Islands), inhabits two different environments: the xeric euphorb shrubland, as is typical for congeneric Canarian species, and the humid laurel forest, a novel habitat for the genus. 2. We investigate genetic, morphological, and ecological variation among individuals of A. bellamyi from the two habitats. DNA sequence data were used to evaluate whether grasshoppers from the two environments represent distinct lineages. Morphological and trophic analyses were performed to assess phenotypic differentiation between the two different habitats. 3. Population genetic analyses support the hypothesis that the euphorb shrubland is the ancestral habitat for this species. Female laurel forest specimens are larger than those inhabiting the euphorb shrubland, and some external body parts exhibit significant morphometric differences between the two populations. Diet of shrubland individuals is completely different from that of laurel forest individuals. Although in each habitat they consume the most abundant plants, individuals are able to select food plants, which appear to be explained by their nutrient content. 4. Our results suggest that A. bellamyi has colonised laurel forest from shrubland, and that this habitat shift has resulted in genetic, morphological, and ecological changes, perhaps as an adaptation to this new habitat. [ABSTRACT FROM AUTHOR]

The knowledge of the family Nicoletiidae in the Canary Islands was limited to two reports of Proatelurina pseudolepisma (Grassi, 1887), a species which belongs to the subfamily Atelurinae. This study provides new data on the occurrence of representatives of Nicoletiidae on these islands and descriptions of two endemic troglobic taxa: Canariletia holosterna gen. n. et sp. n., from the island of Gran Canaria, and Coletinia majorensis sp. n., found in Fuerteventura. The latter belongs to a group of species whose males have asymmetric antennae, so it is compared with those Coletinia of this group. Canariletia gen. n. shows a unique combination of characters inside Nicoletiidae, so its position within this family is discussed, considering the new genus as incertae sedis, but probably related to the Palaearctic and Afrotropical genera included in the subfamily Coletiniinae sensu Mendes, 1988. [ABSTRACT FROM AUTHOR]

Aim The seminal theory of island biogeography, based on changing rates of immigration and extinction, should be seen in a geological context, as an island's maturity influences the richness of its biota. Here, we develop an island biogeography of biotic interactions, recognizing that, besides species richness, biodiversity also encompasses the multitude of interactions among species. By sampling interactions between plants and pollinators across the Canarian archipelago, we illustrate how the local richness, specialization and endemism of biotic interactions vary with island age and area. Location Canary Islands (27.62° N-29.42° N and 13.33° W-18.17° W). Methods On five islands, covering the full age range of the archipelago, plant-pollinator interactions were catalogued and their strength estimated. Network parameters (e.g. interaction richness and specialization) and the number of single-island interactions (equivalent to single-island endemics) were estimated from interaction matrices and related to island area and age. Results Plant species richness, interaction richness and average degree of specialization of pollinator species showed hump-shaped relationships with island age. Pollinator richness varied with island area and plant richness. Plant specialization increased with island age, and the proportion of single-island interactions ( pSII) exhibited a U-shaped relationship with age. Main conclusions The previously reported hump-shaped relationship between species richness and island age, both on the scale of islands and of habitats, was confirmed for plant species in local networks. Both plants and pollinators were more generalized on the youngest island, which may be due to a predominance of generalist colonists. Pollinator specialization peaked on mid-aged islands, whereas plants showed the highest specialization on old islands, potentially reflecting their different life histories. The U-shaped relationship between the proportion of single-island interactions and island age might be explained by (1) young islands having a high proportion of unique interactions, due to interactions between generalists, and (2) old islands having unique interactions due to an accumulation of unique pairwise interactions that have evolved through time. Thus, island age - which not only captures time per se, but also the geomorphological changes of islands - may act as a regional driver of local network structure, and so the contemporary networks we observed across the Canarian archipelago illustrate the development of a network through geological time. [ABSTRACT FROM AUTHOR]

Recent studies on the endemic Canarian genus Purpuraria have shown that the taxonomy of its only recognized species ( P. erna) is probably erroneous. In this study, an integrative revision of the genus is performed, based on a large number of specimens and geographical sampling. As a result, (1) the diagnostic characters at the genus level are re-described, (2) Purpuraria magna n. sp. based on morphological, morphometric and genetic data is described and (3) the taxonomic status of a formerly described subspecies is clarified. Intraspecific and interspecific morphometric differences have been found, indicating that the genus is undergoing a process of morphological diversification. Nevertheless, the possibility of interspecific mating between individuals of the two species is suggested, because no significant differences have been found between their respective calling songs. Genetic analyses using mitochondrial and nuclear DNA sequences suggest that P. erna and P. magna are recent species with evidences of secondary contact episodes in the past. [ABSTRACT FROM AUTHOR]

Geological processes and ecological adaptation are major drivers of diversification on oceanic islands. Although diversification in these islands is often interpreted as resulting from dispersal or island hopping rather than vicariance, this may not be the case in islands with complex geological histories. The island of Tenerife, in the Canary Islands, emerged in the late Miocene as 3 precursor islands that were subsequently connected and reisolated by volcanic cycles. The spider Dysdera verneaui is endemic to the island of Tenerife, where it is widely distributed throughout most island habitats, providing an excellent model to investigate the role of physical barriers and ecological adaptation in shaping within-island diversity. Here, we present evidence that the phylogeographic patterns of this species trace back to the independent emergence of the protoislands. Molecular markers (mitochondrial genes cox1, 16S, and nadl and the nuclear genes ITS-2 and 28S) analyzed from 100 specimens (including a thorough sampling of D. verneaui populations and additional outgroups) identify 2 distinct evolutionary lineages that correspond to 2 precursor islands, each with diagnostic genital characters indicative of separate species status. Episodic introgression events between these 2 main evolutionary lineages explain the observed incongruence between mitochondrial and nuclear markers, probably as a result of the homogenization of their ITS-2 sequence types. The most widespread lineage exhibits a complex population structure, which is compatible with either secondary contact, following connection of deeply divergent lineages, or alternatively, a back colonization from 1 precursor island to another. [ABSTRACT FROM AUTHOR]

Summary: Many continental subterranean water crustaceans (“stygobionts”) display extreme disjunct distributions, where different species in the same genus are isolated on continents or islands separated by broad oceanic expanses [1]. Despite their freshwater habitat, most of these taxa appear to be most closely related to typical marine groups (“thalassoid” origin) [2]. Among the hadzioids—thalassoid amphipods including the stygobiont families Hadziidae, Pseudoniphargidae, and Metacrangonyctidae—several genera are restricted to inland groundwaters ranging from the Caribbean region to the Mediterranean and Middle East, including interspersed oceanic islands [3]. This distribution might have arisen from Tethyan vicariance [4–7] triggered by the sequential occlusion of the former Tethys Sea, a vast circumtropical ocean existing from the Middle Jurassic up to 20 million years ago (mya). Previous studies have been based on morphological analyses or limited DNA sequence data, making it difficult to test this hypothesis [8–10]. We used complete mitochondrial protein-coding gene sequences, mainly obtained by next-generation sequencing methods and a nuclear ribosomal gene to resolve the phylogeny and to establish a time frame for diversification of the family Metacrangonyctidae (Amphipoda). The results were consistent with the plate tectonics vicariance hypothesis, with major diversifications occurring between 96 and 83 mya. [Copyright &y& Elsevier]

An overview of the obligate hypogean fauna in Portugal (including Azores and Madeira archipelagos) is provided, with a list of obligated cave-dwelling species and subspecies, and a general perspective about its conservation. All the available literature on subterranean Biology of Portugal since the first written record in 1870 until today has been revised. A total of 43 troglobiont and 67 stygobiont species and subspecies from 12 orders have been described so far in these areas, included in the so-called Mediterranean hotspot of biodiversity. The subterranean fauna in Portugal has been considered moderately poor with some endemic relicts and it remains to be demonstrated if this fact is still true after investing in standard surveys in cave environments. The major problems related to the conservation of cave fauna are discussed, but it is clear that the protection of this specialized fauna implies an adequate management of surface habitats. [ABSTRACT FROM AUTHOR]

Six polymorphic microsatellite markers have been developed for the Canary endemic ground beetle Trechus flavocinctus, and the performance of primer pairs amplifying these loci in closely related taxa (including two cave-obliged species) has been tested. The number of alleles in T. flavocinctus samples taken from three distant localities in two islands ranged from four to 14 per locus. Observed heterozygosities were from 0.333 to 0.933. These markers could be useful tools to study the population structure and the genetic consequences of island and cave colonization by ground beetles. [ABSTRACT FROM AUTHOR]

The cover image, by Rüdiger Otto et al., is based on the Biodiversity Research Unpaid extinction debts for endemic plants and invertebrates as a legacy of habitat loss on oceanic islands, DOI: 10.1111/ddi.12590. Photo Credit: Miguel Ibanez. [ABSTRACT FROM AUTHOR]

Summary: Phillips et al.[1] reply to our finding that genetic divergence between subterranean metacrangonyctid amphipods from opposite shores of the Atlantic is congruent with vicariance by plate tectonics [2]. They highlight three presumed shortcomings in our analyses: first, the third codon positions of the mitochondrial genes used to reconstruct the metacrangonyctid phylogeny are saturated and consequently should be excluded from the analysis; second, substitution rates across the tree do not fit an uncorrelated lognormally distributed (UCLD) clock, and implementation of a random local clock (RLC) model would be more appropriate; third, the two dates that we used to calibrate the tree are fairly recent compared to the overall tree length, while the inclusion of a deep fossil calibrator could have improved dating. However, much of the criticism of Phillips et al. applies more to their modification of our data set than to the original data themselves. Specifically, their addition of several highly divergent taxa — driven by the necessity to include taxa encompassing the new deep calibration node they propose — largely alters the properties of our original data matrix. We maintain that third codon position saturation and deviation from lognormal rates largely apply to the new and not to the original data set. We also have some concerns about the fossil calibration used by Phillips et al.[1]. [Copyright &y& Elsevier]