How common is common? Rapidly assessing population size and structure of the frog Mantidactylus betsileanus at a site in east‐central Madagascar

Population‐level data are urgently needed for amphibians in light of the ongoing amphibian extinction crisis. Studies focused on population dynamics are not only important for rare species but also for common species which shape ecosystems to a greater degree than those that are rare. Some of the greatest global amphibian species diversity is found in Madagascar, yet there are few studies on the ecology of frog species on the island. We carried out a mark‐recapture study on the widespread frog Mantidactylus betsileanus (Mantellidae: Mantellinae: Mantidactylus) at two adjacent rainforest sites in east‐central Madagascar to assess its population size and structure. To do so, we validated and implemented an individual identification protocol using photographs of the ventral patterns of frogs and identified individuals with photographic‐matching software. Using this rapid, non‐invasive survey method, we were able to estimate a density of 26 and 28 frogs per 100 m² at each of the two sites sampled. Our results show the rainforests near the village of Andasibe, Madagascar support remarkably high amphibian abundance, helping illustrate the significant ecological role of frogs in this ecosystem. Further, individual frog markings allowed us to develop more precise estimates than traditional survey methods. This study provides a blueprint to augment existing population studies or develop new monitoring programs in Madagascar and beyond.     

Phylogeny and genus-level classification of mantellid frogs (Amphibia, Anura)

We propose a novel classification of frogs in the family Mantellidae, based on published phylogenetic information and on a new analysis of molecular data. Our molecular tree for 53 mantellid species is based on 2419 base pairs of the mitochondrial 12S rRNA, 16S rRNA, tRNAVal and cytochrome b genes, and of the nuclear rhodopsin gene. Because the genus Mantidactylus Boulenger sensu lato is confirmed to be paraphyletic with respect to Mantella Boulenger, and is highly diverse in morphology and reproductive biology, we propose to partition Mantidactylus into seven genera by elevating four subgenera to genus rank (Blommersia Dubois, Guibemantis Dubois, Spinomantis Dubois, and Gephyromantis Methuen) and creating two new genera (Boehmantis gen. n. and Wakea gen. n.). In addition, we create the new subgenera Boophis (Sahona) subgen. n., Gephyromantis (Duboimantis) subgen. n., G. (Vatomantis) subgen. n., and Mantidactylus (Maitsomantis) subgen. n. The following species are transferred to Spinomantis, based on their phylogenetic relationships: S. elegans (Guibé) comb. n. (formerly in Mantidactylus subgenus Guibemantis); S. bertini (Guibé) comb. n. and S. guibei (Blommers-Schlösser) comb. n. (both formerly in Mantidactylus subgenus Blommersia); S. microtis (Guibé) comb. n. (formerly in Boophis Tschudi). Within Boophis, the new B. mandraka species group and B. albipunctatus species group are established. Boophis rhodoscelis (Boulenger) is transferred to the B. microtympanum group. The following five species are revalidated: Mantidactylus bellyi Mocquard and M. bourgati Guibé (not junior synonyms of M. curtus (Boulenger)); M. cowanii (Boulenger) (not syn. M. lugubris (Duméril)); M. delormei Angel (not syn. M. brevipalmatus Ahl); Mantella ebenaui (Boettger) (not syn. M. betsileo (Grandidier)). The new classification accounts for recent progress in the understanding of the phylogeny and natural history of these frogs, but it is still tentative for a number of species. Future modifications may be necessary, especially as concerns species now included in Gephyromantis and Spinomantis.Full article published online at: http://www.senckenberg.de/odes/06-11.htm     

Contrasting effects of functionally distinct tadpole species on nutrient cycling and litter breakdown in a tropical rainforest stream

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High mortality and female‐biased operational sex ratio result in low encounter rates and moderate polyandry in a spider

The taxonomy of the Old World bat genus Otomops (Chiroptera: Molossidae) has been the subject of considerable debate. The failure of classical morphological studies to provide consistent patterns regarding interspecific relationships within Otomops has limited any understanding of the evolutionary history of the genus. We used traditional and geometric morphometric approaches to establish the species limits of taxa from sub‐Saharan Africa, the Arabian Peninsula, and Madagascar. Morphometric data supported the recent recognition of three distinct Afrotropical taxa: Otomops madagascariensis from Madagascar; Otomops martiensseni s.s. from southern, eastern, central, and western Africa; and an undescribed taxon from north‐east Africa and the Arabian Peninsula. Analyses of craniodental measurements and landmark‐based data showed significant cranial size and shape divergence between the three taxa. Cranial size and shape variation within Afro‐Arabian Otomops were strongly influenced by altitude, seasonality of precipitation, and precipitation in the driest month. Based on morphometric patterns and molecular divergence estimates, we suggest that morphological evolution within Afro‐Arabian Otomops occurred in response to the fluctuating climate during the Pleistocene on the one hand, and the increasing aridity and seasonality over north‐eastern Africa on the other. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, •• , ••–••.     

Deforestation alters the resource base and biomass of endemic stream insects in eastern Madagascar

1. Rainforest streams in eastern Madagascar have species‐rich and diverse endemic insect communities, while streams in deforested areas have relatively depauperate assemblages dominated by collector‐gatherer taxa. We sampled a suite of benthic insects and their food resources in three primary rainforest streams within Ranomafana National Park in eastern Madagascar and three agriculture streams in the park's deforested peripheral zone. We analysed gut contents and combined biomass and stable isotope data to examine stream community responses to deforestation in the region, which is a threatened and globally important hotspot for freshwater biodiversity. 2. Gut analyses showed that most taxa depended largely on amorphous detritus, obtained either from biofilms (collector‐gatherers) or from seston (microfilterers). Despite different resource availability in forest versus agriculture streams, diets of each taxon did not differ between stream types, suggesting inflexible feeding modes. Carbon sources for forest stream insects were difficult to discern using δ¹³C. However, in agriculture streams dependence on terrestrial carbon sources was low relative to algal sources. Most insect taxa with δ¹³C similar to terrestrial carbon sources (e.g. the stonefly Madenemura, the caddisfly Chimarra sp. and Simulium blackflies) were absent or present at lower biomass in agriculture streams relative to forest streams. Conversely, collector‐gatherers (Afroptilum mayflies) relied on algal carbon sources and had much higher biomass in agriculture streams. 3. Our analyses indicate that a few collector‐gatherer species (mostly Ephemeroptera) can take advantage of increased primary production in biofilms and consequently dominate biomass in streams affected by deforestation. In contrast, many forest stream insects (especially those in the orders Plecoptera, Trichoptera and Diptera) depend on terrestrial carbon sources (i.e. seston and leaf litter), are unable to track resource availability and consequently decline in streams draining deforested landscapes. These forest‐specialists are often micro‐endemic and particularly vulnerable to deforestation. 4. The use of consumer biomass data in stable isotope research can help detect population‐level responses to shifts in basal resources caused by anthropogenic change. We also suggest that restoration of vegetated riparian zones in eastern Madagascar and elsewhere could mitigate the deleterious effects of deforestation on sensitive, endemic stream taxa that are dependent on terrestrial carbon sources.     

Molecular systematics of mantelline frogs from Madagascar and the evolution of their femoral glands

Several genera of frogs from Madagascar, classified in the family Mantellidae, subfamily Mantellinae, possess structures commonly called 'femoral glands' on the ventral side of their shanks. The question arises as to the origin and phylogenetic significance of these glands. A molecular phylogeny based on 3601 nucleotide DNA sequences of three mitochondrial and two nuclear genes of 30 mantellid species provided strong support for monophyly of the included mantellines, all characterized by enlarged femoral gland clusters, as well as for those with gland clusters of coordinated central arrangement of secretion ducts. However, the phylogeny also strongly supported the hypothesis of convergent evolution of structurally similar glands in unrelated frogs ( Indirana , Petropedetes ), and several trends of convergent evolution of gland structure within mantellines. We studied the light microscopic structure of the femoral glands in a representative array of 18 mantellid species. Males of all species of the subfamily Mantellinae were characterized by clusters of distinct single glands. Each was structurally similar to an enlarged granular gland and secreted independently, probably through a single duct. By contrast, the largely semi-aquatic frogs in the genus Mantidactylus had a specialized cluster of glands, in which the secretion ducts led into a macroscopically recognizable central depression. In Boophis opisthodon , a mantellid species of the subfamily Boophinae without externally recognizable femoral glands, we observed a large number of enlarged granular glands of various sizes in the ventral skin of the shank. This observation is consistent with the hypothesis that the large and more uniform organs of mantellines are derived granular glands.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 92 , 529–539.     

Combining traditional morphometrics and molecular markers in cryptic taxa: towards an updated integrative taxonomic treatment for Veronica subgenus Pentasepalae (Plantaginaceae sensu APG II) in the western Mediterranean

The aim of this study was to quantify the phenotypic differences amongst the taxa included in Veronica subgenus Pentasepalae, represented in the western Mediterranean area. In combination with previously obtained data on genotypic differences, this enabled the recognition of eight taxonomic units. The delimitation of the boundaries among species and subspecies was mainly based on molecular data, whereas the best characters to discriminate taxa were selected after an accurate study of herbarium material and living populations. Such a selection was also supported by a detailed morphometric study of 30 quantitative leaf traits in 88 populations. Several morphological characters, including the length of the trichomes, length of the petiole and leaf division, were found to be robust, and could be useful in the identification of the taxa involved. As a conclusion, a key to the taxa is proposed, as well as a complete nomenclatural treatment for the group, which includes the typification of several names. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 68–87.     

Molecular phylogeny of the subgenus Holothuria (Selenkothuria) Deichmann, 1958 (Holothuroidea: Aspidochirotida)

The subgenus Selenkothuria comprises 12 species of tropical shallow water sea cucumbers that share morphological features, such as rods in the body wall and tube feet, modified tentacles for suspension feeding, and cryptic colours. The taxonomic status of this taxon has been controversial, but currently it is accepted as a subgenus of the genus Holothuria. Phylogenetic analyses of mitochondrial genes [cytochrome c oxidase subunit 1 (COI), 16S RNA] of ten species of Selenkothuria and related subgenera showed the polyphyly of this subgenus; monophyly was rejected by a likelihood ratio test. A geographical split divides the species of this subgenus into three different groups: one Indo‐West‐Pacific (IWP) group and two American groups. The IWP group is more closely related to Holothuria (Semperothuria) cinerascens and to other subgenera such as Roweothuria, Holothuria, and Vaneyothuria, whereas the two American groups are more closely related to each other and to some species of the subgenus Halodeima. These results suggest multiple parallel originations and diversification of ossicle morphology within the subgenus Selenkothuria. The current scheme of subgenera for the genus Holothuria is not supported, suggesting the need for a new classification. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 165 , 109–120.     

Characterization of 20 microsatellite marker loci in the red‐bellied brown lemur (Eulemur rubriventer)

Twenty nuclear microsatellite loci were isolated from a genomic DNA library derived from a free‐ranging red‐bellied brown lemur (Eulemur rubriventer), from the Ranomafana National Park, Madagascar. Population genetic parameters were estimated as baseline values from samples collected from populations harboured in the Ranomafana and Andringitra National Parks. The marker suite will be used in a future study on the population dynamics of this species.     

Geographic morphological variation in parapatric Western Palearctic tree frogs,Hyla arborea and Hyla savignyi: are related species similarly affected by climatic conditions?

Tree frogs Hyla arborea and Hyla savignyi are similar, closely‐related species distributed in Europe and the Middle East. We investigated geographic variation in body shape within and between these species, and tested its relationships to macroclimatic conditions. We used morphometric distances (based on size corrected external measurements) to construct phenetic trees (unweighted pair‐group method of arithmetical averages, Neighbour‐joining), and to test correlations between morphology, geography, and climate by the partial Mantel test. Regardless of their specific affiliation, the parapatric populations of both species from the eastern Mediterranean, where they occupy comparable habitats, are closer to each other in morphospace than to conspecific populations from distal regions. This local interspecific similarity is probably driven by the common response to environment, expressed here as macroclimatic conditions. In support, the geographically close but ecologically vicariant populations of both species from the Caucasus region differ quite substantially in body shape. We suggest that climate‐provoked phenotypic variation in closely‐related parapatric species should be taken into account as a potential complication to character displacement in morphology. Contrariwise, morphological diversification between related species or their populations could be enhanced by habitat shifts resulting in occupation of different environmental space. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 95 , 539–556.     

Pollen morphology and systematics of palaeotropical Phyllanthus and related genera of subtribe Phyllanthinae (Euphorbiaceae)

The observations of pollen from 27 species of subtribe Phyllanthinae using scanning electron microscopy reveal considerable morphological diversity in palaeotropical Phyllanthus and the related palaeotropical genera Breynia, Glochidion, and Sauropus. The tribe appears to be monophyletic, but the pollen morphology does not support the monophyly of Phyllanthus or Sauropus. Within Phyllanthus, the pollen characters suggest a close relationship between the subgenera Emblica and Phyllanthodendron. They also reveal a surprising morphological congruence between the pollen grains of section Ceramanthus (subgenus Isocladus) and those of subgenus Eriococcus, although it is not clear whether this similarity is homoplastic. The presence of diploporate colpi is a synapomorphy uniting Breynia and Sauropus, but may be homoplastic in Phyllanthus. The affinities suggested by the morphological features of the pollen in the Phyllanthinae are concordant with recent molecular phylogenies. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 157 , 591–608.     

Take time to smell the frogs: vocal sac glands of reed frogs (Anura: Hyperoliidae) contain species‐specific chemical cocktails

Males of all reed frog species (Anura: Hyperoliidae) have a prominent, often colourful, gular patch on their vocal sac, which is particularly conspicuous once the vocal sac is inflated. Although the presence, shape, and form of the gular patch are well‐known diagnostic characters for these frogs, its function remains unknown. By integrating biochemical and histological methods, we found strong evidence that the gular patch is a gland producing volatile compounds, which might be emitted while calling. Volatile compounds were confirmed by gas chromatography–mass spectrometry in the gular glands in 11 species of the hyperoliid genera Afrixalus, Heterixalus, Hyperolius, and Phlyctimantis. Comparing the gular gland contents of 17 specimens of four sympatric Hyperolius species yielded a large variety of 65 compounds in species‐specific combinations. We suggest that reed frogs might use a complex combination of at least acoustic and chemical signals in species recognition and mate choice. © 2013 The Authors. Biological Journal of the Linnean Society published by John Wiley & Sons Ltd on behalf of The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110 , 828–838.     

Rapid Response to Evaluate the Presence of Amphibian Chytrid Fungus (Batrachochytrium dendrobatidis) and Ranavirus in Wild Amphibian Populations in Madagascar

We performed a rapid response investigation to evaluate the presence and distribution of amphibian pathogens in Madagascar following our identification of amphibian chytrid fungus (Batrachochytrium dendrobatidis, Bd) and ranavirus in commercially exported amphibians. This targeted risk-based field surveillance program was conducted from February to April 2014 encompassing 12 regions and 47 survey sites. We simultaneously collected amphibian and environmental samples to increase survey sensitivity and performed sampling both in wilderness areas and commercial amphibian trade facilities. Bd was not detected in any of 508 amphibian skin swabs or 68 water filter samples, suggesting pathogen prevalence was below 0.8%, with 95% confidence during our visit. Ranavirus was detected in 5 of 97 amphibians, including one adult Mantidactylus cowanii and three unidentified larvae from Ranomafana National Park, and one adult Mantidactylus mocquardi from Ankaratra. Ranavirus was also detected in water samples collected from two commercial amphibian export facilities. We also provide the first report of an amphibian mass-mortality event observed in wild amphibians in Madagascar. Although neither Bd nor ranavirus appeared widespread in Madagascar during this investigation, additional health surveys are required to disentangle potential seasonal variations in pathogen abundance and detectability from actual changes in pathogen distribution and rates of spread. Accordingly, our results should be conservatively interpreted until a comparable survey effort during winter months has been performed. It is imperative that biosecurity practices be immediately adopted to limit the unintentional increased spread of disease through the movement of contaminated equipment or direct disposal of contaminated material from wildlife trade facilities. The presence of potentially introduced strains of ranaviruses suggests that Madagascar''s reptile species might also be threatened by disease. Standardized population monitoring of key amphibian and reptile species should be established with urgency to enable early detection of potential impacts of disease emergence in this global biodiversity hotspot.     

Morphological and molecular taxonomy of a new Daptonema (Nematoda,Xyalidae) with comments on the systematics of some related taxa

A new species of Daptonema is described based upon morphological characters and 18S rRNA sequence. Daptonema matrona sp. nov. was collected in Pina Basin (north‐eastern Brazil). It differs from all other species of the genus by the presence of reduced cephalic setae and straight spicules. These features require an adaptation of the generic diagnosis. Moreover, the females are characterized by intra‐uterine development of the offspring, considered herein as their major autapomorphic feature. Molecular systematic analyses supported Daptonema matrona sp. nov. as a distinct genetic and evolutionary lineage. The data also indicate hypotheses of taxonomic synonymies amongst some related taxa from Xyalidae as well as the paraphyly of Daptonema. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 1–15.     

Do tadpoles affect leaf decomposition in neotropical streams?

1. Of the relatively few studies that have examined consequences of amphibian declines on stream ecosystems, virtually all have focused on changes in algae (or algal‐based food webs) and little is known about the potential effects of tadpoles on leaf decomposition. We compared leaf litter decomposition dynamics in two neotropical streams: one with an intact community of tadpoles (with frogs) and one where tadpoles were absent (frogless) as a result of a fungal pathogen that had driven amphibians locally extinct. The stream with tadpoles contained a diverse assemblage (23 species) of larval anurans, and we identified five species of glass frog (Centrolenidae) tadpoles that were patchily distributed but commonly associated with leaf detritus and organic sediments in pools. The latter reached total densities of 0–318 tadpoles m^?2. 2. We experimentally excluded tadpoles from single‐species leaf packs incubated over a 40‐day period in streams with and without frogs. We predicted that decomposition rates would be higher in control (allowing access of tadpoles) treatments in the study stream with frogs than in the frogless stream and, in the stream with frogs, in the control than in the tadpole exclusion treatment. 3. In the stream with frogs, Centrolene prosoblepon and Cochranella albomaculata tadpoles were patchily distributed in leaf packs (0.0–33.3 m^?2). In contrast to our predictions, leaf mass loss and temperature‐corrected leaf decomposition rates in control treatments were almost identical in our stream with frogs (41.01% AFDM lost, k_{degree day} = ?0.028 day^?1) and in the frogless stream (41.81% AFDM lost, k_{degree day} = ?0.027 day^?1) and between control and tadpole exclusion treatments within each stream. Similarly, there were no significant differences in leaf pack bacterial biomass, microbial respiration rates or macroinvertebrate abundance between treatments or streams. Invertebrate assemblages on leaf packs were similar between treatments (SIMI = 0.97) and streams (SIMI = 0.95) and were dominated by larval Chironomidae, Simuliidae (Diptera) and larval Anchytarsus spp. (Coleoptera). 4. In contrast to dramatic effects of grazing tadpoles on algal communities observed previously, tadpoles had no major effects on decomposition. While centrolenid tadpoles were common in the stream with frogs, their patchy distribution in both experimental and natural leaf packs suggests that their effects on detrital dynamics and microbes are probably more localised than those of grazing tadpoles on algae.     

Systematic revision of the genus Aglyptodactylus Boulenger, 1919 (Amphibia: Ranidae), and analysis of its phylogenetic relationships to other Madagascan ranid genera (Tomopterna, Boophis, Mantidactylus, and Mantella)

Recent field studies revealed two new species of the genus Aglyptodactylus (Amphibia: Anura: Ranidae), which was hitherto considered as monotypic and confined to humid eastern Madagascar. Both new species, Aglyptodactylus laticeps sp. n. and Aglyptodactylus securifer sp. n. , occur syntopically in the deciduous dry forest of Kirindy in western Madagascar. In comparison to Aglyptodactylus madagascariensis from eastern rainforests, the new species A. laticeps shows a remarkable morphological divergence, which may be partly due to adaptations to burrowing habits in dry environments. Despite of the morphological differentiation, advertisement calls and osteology indicate that all three species of Aglyptodactylus are closely related. A phylogenetic analysis of the Madagascan ranid genera Aglyptodactylus, Mantella, Mantidactylus, Boophis , and Tomopterna (the latter including species from Madagascar, Africa, and Asia) strongly supports a sister group relationship of Aglyptodactylus with the ranine genus Tomopterna . We therefore transfer Aglyptodactylus from the Rhacophorinae to the Raninae and discuss implications of this rearrangement for ranoid systematics. The existence of the endemic genus Aglyptodactylus in Madagascar as well as its close phylogenetic relationships to Tomopterna confirm that the Raninae were already present on the Madagascan plate before its separation from Africa. The Madagascan Tomopterna labrosa shows several important differences both to Asian and to African species of the genus, and is therefore transferred from the subgenus Sphaerotheca (now restricted to Asia) to a new subgenus Laliostoma subgen. n .