Representative Taxa Research Articles

The genus Chamaecrista Moench in a fragment of the Ecological Station Raso da Catarina, Bahia, Brazil

Abstract Chamaecrista has a Pantropical distribution, with some occurrences in Australia and temperate areas, and includes about 330 species, of which 266 occur in the Americas. The genus is represented in Brazil by 256 species, of which 97 are cited for the northeast Region. The Ecological Station Raso da Catarina (ESRC) is one of the largest areas of protected Caatinga and occupies about 105,282.00 ha., delimited by the coordinates 09°39’0.30” to 09°50’98.2” S and 38°26’57.5” to 38°29’32.6” W. The floristic survey of Chamaecrista in the ESRC included analysis of specimens collected from March 2010 and October 2011. The analyses were supplemented with dried collections from the following herbaria: ALCB, EAC, HRB, HUEFS and MBM. The genus is represented in the study area by ten taxa. The most representative taxa in the area were Chamaecrista repens (Vogel) H.S.Irwin & Barneby var. multijuga (Benth.) H.S.Irwin & Barneby, C. brevicalyx (Benth.) H.S.Irwin & Barneby var. brevicalyx, C. belemii (H.S.Irwin & Barneby) H.S.Irwin & Barneby var. belemii, wich are directly related to sandy soils common in the region. The taxonomic treatment includes a key for the identification, descriptions, illustrations, photos, data geographical distribution, reproductive phenology and comments about the taxa.

Morphological and genetic diversity of Beaufort Sea diatoms with high contributions from the Chaetoceros neogracilis species complex.

Seventy-five diatom strains isolated from the Beaufort Sea (Canadian Arctic) in the summer of 2009 were characterized by light and electron microscopy (SEM and TEM), as well as 18S and 28S rRNA gene sequencing. These strains group into 20 genotypes and 17 morphotypes and are affiliated with the genera Arcocellulus, Attheya, Chaetoceros, Cylindrotheca, Eucampia, Nitzschia, Porosira, Pseudo-nitzschia, Shionodiscus, Thalassiosira, and Synedropsis. Most of the species have a distribution confined to the northern/polar area. Chaetoceros neogracilis and Chaetoceros gelidus were the most represented taxa. Strains of C.neogracilis were morphologically similar and shared identical 18S rRNA gene sequences, but belonged to four distinct genetic clades based on 28S rRNA, ITS-1 and ITS-2 phylogenies. Secondary structure prediction revealed that these four clades differ in hemi-compensatory base changes (HCBCs) in paired positions of the ITS-2, suggesting their inability to interbreed. Reproductively isolated C.neogracilis genotypes can thus co-occur in summer phytoplankton communities in the Beaufort Sea. C.neogracilis generally occurred as single cells but also formed short colonies. It is phylogenetically distinct from an Antarctic species, erroneously identified in some previous studies as C.neogracilis, but named here as Chaetoceros sp. This work provides taxonomically validated sequences for 20 Arctic diatom taxa, which will facilitate future metabarcoding studies on phytoplankton in this region.

Biometric assessment of deep-sea vent megabenthic communities using multi-resolution 3D image reconstructions

This paper describes a method to survey the distribution of megabenthos over multi-hectare regions of the seafloor. Quantitative biomass estimates are made by combining high-resolution 3D image reconstructions, used to model spatial relationships between representative taxa, with lower-resolution reconstructions taken over a wider area in which the distribution of larger predatory animals can be observed. The method is applied to a region of the Iheya North field that was the target of scientific drilling during the IODP Expedition 331 in 2010. An area of 2.5ha was surveyed 3 years and 4 months after the site was drilled. More than 100,000 organisms from 6 taxa were identified. The visible effects of drilling on the distribution of megabenthos were confined to a 20m radius of the artificially created hydrothermal discharges, with the associated densities of biomass lower than observed in nearby naturally discharging areas.

Ant community (Hymenoptera: Formicidae) associated with Callisthene fasciculata (Spr.) Mart. (Vochysiaceae) canopies in the Pantanal of Poconé, Mato Grosso, Brazil

Ants act in different trophic levels and are important due to their abundance, distribution and diversity in a variety of habitats, exercising influence on many different organisms and ecosystems. Thus, this study compared temporal variation on the structure and composition of the Formicidae community in canopies of Callisthene fasciculata (Spr.) Mart. (Vochysiaceae) during high water and dry periods, in the Pantanal of Poconé, Mato Grosso, Brazil. Ant sampling was performed on 12 specimens of C. fasciculata, in 2010 and 2011, using canopy fogging with insecticide, in a total of 120m² of sampled canopy. Altogether, 2,958 ants were collected. The 2,943 adults were distributed in four subfamilies, 12 genus and 26 species. Myrmicinae (18.7 ind./m2) was the most representative taxon, followed by Formicinae (3.2 ind./m2), Dolichoderinae (2.2 ind./m2) and Pseudomyrmecinae (0.3 ind./m2). The community is made up of six trophic groups, in which omnivorous (23.5 ind./m2) were the most prevalent, followed by minimum hypogeical generalists (0.5 ind./m2) and arboreal generalist predators (0.3 ind./m2). Although the results showed that Formicidae community richness, associated to C. fasciculata canopies, does not represent a significant difference among the seasonal periods, there are differences as to species distribution and grouping in trophic guilds on the host plant over the seasonal periods, indicating the influence of temporal variation, and therefore, habitat conditions on this community.

Assembled Plastid and Mitochondrial Genomes, as well as Nuclear Genes, Place the Parasite Family Cynomoriaceae in the Saxifragales.

Cynomoriaceae, one of the last unplaced families of flowering plants, comprise one or two species or subspecies of root parasites that occur from the Mediterranean to the Gobi Desert. Using Illumina sequencing, we assembled the mitochondrial and plastid genomes as well as some nuclear genes of a Cynomorium specimen from Italy. Selected genes were also obtained by Sanger sequencing from individuals collected in China and Iran, resulting in matrices of 33 mitochondrial, 6 nuclear, and 14 plastid genes and rDNAs enlarged to include a representative angiosperm taxon sampling based on data available in GenBank. We also compiled a new geographic map to discern possible discontinuities in the parasites’ occurrence. Cynomorium has large genomes of 13.70–13.61 (Italy) to 13.95–13.76 pg (China). Its mitochondrial genome consists of up to 49 circular subgenomes and has an overall gene content similar to that of photosynthetic angiosperms, while its plastome retains only 27 of the normally 116 genes. Nuclear, plastid and mitochondrial phylogenies place Cynomoriaceae in Saxifragales, and we found evidence for several horizontal gene transfers from different hosts, as well as intracellular gene transfers.

Leifiporia rhizomorpha gen. et sp. nov. and L. eucalypti comb. nov. in Polyporaceae (Basidiomycota)

A new poroid wood-inhabiting fungal genus, Leifiporia, is proposed, based on morphological and molecular evidence, which is typified by L. rhizomorpha sp. nov. The genus is characterized by an annual growth habit, resupinate basidiocarps with white to cream pore surface, a dimitic hyphal system with generative hyphae bearing clamp connections and branching mostly at right angles, skeletal hyphae present in the subiculum only and distinctly thinner than generative hyphae, IKI–, CB–, and ellipsoid, hyaline, thin-walled, smooth, IKI–, CB– basidiospores. Sequences of ITS and LSU nrRNA gene regions of the studied samples were generated, and phylogenetic analyses were performed with maximum likelihood, maximum parsimony and Bayesian inference methods. The phylogenetic analysis based on molecular data of ITS + nLSU sequences showed that Leifiporia belonged to the core polyporoid clade and was closely related to Diplomitoporus overholtsii and Lopharia cinerascens, and then grouped with Pycnoporus and Trametes. Further investigation was obtained for more representative taxa in the Polyporaceae based on nLSU sequences, in which the results demonstrated that the genus Leifiporia formed a monophyletic lineage with a strong support (100 % BS, 100 % BP, 1.00 BPP). Both morphological and molecular evidence confirmed the placement of the new genus in the core polyporoid clade. In addition, a new combination, Leifiporia eucalypti, is proposed based on examination of its type material and phylogeny.

Ediacaran distributions in space and time: testing assemblage concepts of earliest macroscopic body fossils

AbstractThe mid-late Ediacaran Period (~579–541 Ma) is characterized by globally distributed marine soft-bodied organisms of unclear phylogenetic affinities colloquially called the “Ediacara biota.” Despite an absence of systematic agreement, previous workers have tested for underlying factors that may control the occurrence of Ediacaran macrofossils in space and time. Three taxonomically distinct “assemblages,” termed the Avalon, White Sea, and Nama, were identified and informally incorporated into Ediacaran biostratigraphy. After ~15 years of new fossil discoveries and taxonomic revision, we retest the validity of these assemblages using a comprehensive database of Ediacaran macrofossil occurrences. Using multivariate analysis, we also test the degree to which taphonomy, time, and paleoenvironment explain the taxonomic composition of these assemblages. We find that: (1) the three assemblages remain distinct taxonomic groupings; (2) there is little support for a large-scale litho-taphonomic bias present in the Ediacaran; and (3) there is significant chronostratigraphic overlap between the taxonomically and geographically distinct Avalonian and White Sea assemblages ca. 560–557 Ma. Furthermore, both assemblages show narrow bathymetric ranges, reinforcing that they were paleoenvironmental–ecological biotopes and spatially restricted in marine settings. Meanwhile, the Nama assemblage appears to be a unique faunal stage, defined by a global loss of diversity, coincident with a noted expansion of bathymetrically unrestricted, long-ranging Ediacara taxa. These data reinforce that Ediacaran biodiversity and stratigraphic ranges of its representative taxa must first statistically account for varying likelihood of preservation at a local scale to ultimately aggregate the Ediacaran macrofossil record into a global biostratigraphic context.

Decoupled form and function in disparate herbivorous dinosaur clades.

Convergent evolution, the acquisition of morphologically similar traits in unrelated taxa due to similar functional demands or environmental factors, is a common phenomenon in the animal kingdom. Consequently, the occurrence of similar form is used routinely to address fundamental questions in morphofunctional research and to infer function in fossils. However, such qualitative assessments can be misleading and it is essential to test form/function relationships quantitatively. The parallel occurrence of a suite of morphologically convergent craniodental characteristics in three herbivorous, phylogenetically disparate dinosaur clades (Sauropodomorpha, Ornithischia, Theropoda) provides an ideal test case. A combination of computational biomechanical models (Finite Element Analysis, Multibody Dynamics Analysis) demonstrate that despite a high degree of morphological similarity between representative taxa (Plateosaurus engelhardti, Stegosaurus stenops, Erlikosaurus andrewsi) from these clades, their biomechanical behaviours are notably different and difficult to predict on the basis of form alone. These functional differences likely reflect dietary specialisations, demonstrating the value of quantitative biomechanical approaches when evaluating form/function relationships in extinct taxa.

Uso de Macroinvertebrados bentónicos como bioindicadores de calidad del agua del río Palacagüina, Norte de Nicaragua

El río Palacagüina se ubica en las coordenadas con latitud N 13º27ʹ48ʹʹ y longitud W 86º24ʹ25ʹʹ; la Ley de Aguas Nacionales de Nicaragua norma como zona de protección de fuentes de agua una franja de 200 metros a ambos lados del río; sin embargo el 58.95% de la superficie es utilizada para agricultura y ganadería que aportan una gran cantidad de nutrientes y elementos contaminantes al agua.El objetivo de este estudio es Comparar la calidad del agua del Río Palacagüina parte alta versus parte baja mediante la utilización de macroinvertebrados bentónicos como bioindicadores de calidad de agua. El fin principal de este río es el abastecimiento de agua potable a través del sistema de galería de infiltración al 46.67% de la población total del Municipio de Palacagüina estimada en 15,003; INIFOM, 2012.Durante el estudio se registraron 11 órdenes y 31 taxa; las taxas más representativas fueron Gomphidae (32.4%), Naucoridae (23.47%) y Libellulidae (16.85%). Los resultados del estudio de la calidad del agua del río Palacagüina utilizando el índice biological monitoring working party adaptado para Costa Rica (BMWP – CR) sugiere que las aguas del Río Palacagüina están contaminadas.

Composition and genomic organization of arthropod Hox clusters.

BackgroundThe ancestral arthropod is believed to have had a clustered arrangement of ten Hox genes. Within arthropods, Hox gene mutations result in transformation of segment identities. Despite the fact that variation in segment number/character was common in the diversification of arthropods, few examples of Hox gene gains/losses have been correlated with morphological evolution. Furthermore, a full appreciation of the variation in the genomic arrangement of Hox genes in extant arthropods has not been recognized, as genome sequences from each major arthropod clade have not been reported until recently. Initial genomic analysis of the chelicerate Tetranychusurticae suggested that loss of Hox genes and Hox gene clustering might be more common than previously assumed. To further characterize the genomic evolution of arthropod Hox genes, we compared the genomic arrangement and general characteristics of Hox genes from representative taxa from each arthropod subphylum.ResultsIn agreement with others, we find arthropods generally contain ten Hox genes arranged in a common orientation in the genome, with an increasing number of sampled species missing either Hox3 or abdominal-A orthologs. The genomic clustering of Hox genes in species we surveyed varies significantly, ranging from 0.3 to 13.6 Mb. In all species sampled, arthropod Hox genes are dispersed in the genome relative to the vertebrate Mus musculus. Differences in Hox cluster size arise from variation in the number of intervening genes, intergenic spacing, and the size of introns and UTRs. In the arthropods surveyed, Hox gene duplications are rare and four microRNAs are, in general, conserved in similar genomic positions relative to the Hox genes.ConclusionsThe tightly clustered Hox complexes found in the vertebrates are not evident within arthropods, and differential patterns of Hox gene dispersion are found throughout the arthropods. The comparative genomic data continue to support an ancestral arthropod Hox cluster of ten genes with a shared orientation, with four Hox gene-associated miRNAs, although the degree of dispersion between genes in an ancestral cluster remains uncertain. Hox3 and abdominal-A orthologs have been lost in multiple, independent lineages, and current data support a model in which inversions of the Abdominal-B locus that result in the loss of abdominal-A correlate with reduced trunk segmentation.Electronic supplementary materialThe online version of this article (doi:10.1186/s13227-016-0048-4) contains supplementary material, which is available to authorized users.

Karyological studies of six taxa of the genusAlliumL. (Amaryllidaceae) from Turkey

AbstractKaryotype structures in representative taxa of the genus Allium L. are compared, based on Feulgen-stained somatic metaphase chromosomes. The karyotypes of Allium arlgirdense, A. anacoleum and A. microspathum (in subg. Allium), and A. rhetoreanum and A. shirnakense (in subg. Melanocrommyum) are described for the first time. The karyological analyses indicate the relationships among the species with respect to asymmetry indices. All Allium taxa studied are diploid with 2n = 2x = 16 chromosomes. One B chromosome is detected in the chromosomes of A. microspathum. All chromosome sets of the studied taxa consist of seven median chromosomes and one submedian chromosomes and all submetacentric pairs bear a satellite on the short arms. The lengths of the chromosomes show remarkable differences particularly at the subgenus level. The three subgenus of genus Allium show a clear tendency to have karyotypes distinct on asymmetry grounds. Karyotype asymmetry relationships are discussed according to the bidimens...

Increasing land use drives changes in plant phylogenetic diversity and prevalence of specialists.

Increased human land use has resulted in the increased homogenization of biodiversity between sites, yet we lack sufficient indicators to predict which species decline and the consequence of their potential loss on ecosystem services. We used comparative phylogenetic analysis to (1) characterize how increasing conversion of forest and grasslands to grazing pasturelands changes plant diversity and composition; (2) examine how changes in land use relate to declines in functional trait diversity; and (3) specifically investigate how these changes in plant composition affect the prevalence of zygomorphy and the possible consequences that these changes may have on pollinator functional groups. As predicted, we found that the conversion to grazing pasturelands negatively impacted species richness and phylogenetic composition. Clades with significantly more represented taxa in grasslands (GL) were genera with a high representation of agricultural weeds, while the composition was biased towards clades of subalpine herbaceous wildflowers in Mixed Forest (MF). Changes in community composition and structure had strong effects on the prevalence of zygomorphic species likely driven by nitrogen-fixing abilities of certain clades with zygomorphic flowers (e.g., Fabaceae). Land conversion can thus have unexpected impacts on trait distributions relevant for the functioning of the community in other capacities (e.g., cascading effects to other trophic levels (i.e., pollinators). Finally, the combination of traits represented by the current composition of species in GL and MF might enhance the diagnostic value of productivity and ecosystem processes in the most eroded ecosystems.

Annotated checklist of Echinoderms from Araçá Bay, Southeastern Brazil

We present a species list of echinoderms from Araçá Bay, state of São Paulo. Altogether, 863 specimens belonging to 25 species, 19 genera, and 13 families were exhaustively collected during three years in consolidated and non-consolidated substrate. Ophiuroidea was the most representative taxon with 16 species, follow by Asteroidea with four species, Echinoidea with three, and Holothuroidea with two species. The brittle stars Amphiura kinbergi and Ophiothela cf. mirabilis are new records for Araçá Bay. We confirm that Araçá Bay is one of the best known area of echinoderm diversity in Brazil considering that the perimeter (3 km) of the bay corresponds to only 0.03% of the Brazilian coastline (8500 km). This work complements the knowledge of Araçá Bay biodiversity and supports future interventions, management and maintaining the diversity of this wonderful group of marine animals.

Composition of the Cockroach Gut Microbiome in the Presence of Parasitic Nematodes.

Cockroaches are parasitized by thelastomatid nematodes, which live in an obligate manner in their hindgut and interact with the resident microbial community. In the present study, a composition analysis was performed on the gut microbiome of Periplaneta fuliginosa and P. americana to investigate natural and artificial infection by thelastomatid nematodes. Nine libraries of the 16S rRNA gene V3–V4 region were prepared for pyrosequencing. We examined the complete gut microbiome (fore-, mid-, and hindgut) of lab-reared P. fuliginosa naturally infected with the parasitic nematode Leidynema appendiculatum and those that were nematode-free, and complemented our study by characterizing the hindgut microbial communities of lab-reared P. americana naturally infected with Hammerschmidtiella diesingi and Thelastoma bulhoesi, artificially infected with L. appendiculatum, and those that were nematode-free. Our results revealed that the fore- and midgut of naturally infected and nematode-free P. fuliginosa have close microbial communities, which is in contrast with hindgut communities; the hindgut communities of both cockroaches exhibit higher microbial diversities in the presence of their natural parasites and marked differences were observed in the abundance of the most representative taxa, namely Firmicutes, Proteobacteria, and Bacteroidetes. Our results have provided basic information and encourage further studies on multitrophic interactions in the cockroach gut as well as the thelastomatid nematodes that play a role in this environment.

Monitoreo de la carga fúngica ambiental y de otros bioaerosoles en un depósito de restos momificados del NOA del Museo de la Plata (Argentina): un estudio de caso.

El objetivo del trabajo fue llevar a cabo un relevamiento de la carga fúngica ambiental y otros bioaerosoles asociados a un depósito de restos momificados del NOA del Museo de La Plata. Se realizaron dos tipos de monitoreos, i) uno del tipo aerobiológico (viable y no viable) en el aire exterior del depósito, en el aire interior del mismo y en el interior de 3 de sus vitrinas donde se hallan restos humanos; y ii) otro que consistió en el estudio y cultivo de la micobiota asociada a la superficie de materiales con signos evidentes de deterioro. En base al muestreo aerobiológico, se registró la mayor diversidad y concentración esporal en el ambiente exterior siendo Alternaria sp., Cladosporium cladosporioides y Penicillium sp. los taxa más representativos. Aunque el interior del depósito como de cada vitrina analizada mostró una carga fúngica particular, la abundancia de las esporas correspondientes a Aspergillus sp., Cladosporium sp. y Penicillium sp. fue característica. El análisis de las muestras de contacto evidenció la presencia de Cladosporium herbarum, Penicillium frequentans y Talaromyces helicus en asociación a las momias analizadas. El conocimiento de los hongos presentes en ambientes interiores y sobre materiales de valor patrimonial constituye un elemento clave para el establecimiento de pautas de control para su conservación.

Phylogeny and systematics of mitriform gastropods (Mollusca: Gastropoda: Neogastropoda)

With about 800 Recent species, ‘miters’ are a widely distributed group of tropical and subtropical gastropods that are most diverse in the Indo-West Pacific. They include the two families Mitridae and Costellariidae, similar in shell morphology and traditionally treated as close relatives. Some genera of deep-water Ptychatractidae and Volutomitridae are close to miters in shell morphology, and the term ‘mitriform gastropods’ has been introduced to refer to Mitridae, Costellariidae, and this assortment of convergent forms. The present study aimed at the reconstruction of phylogenetic relationships of mitriform gastropods based on representative taxon sampling. Four genetic markers [cytochrome c oxidase subunit I (COI), 16S and 12S rRNA mitochondrial genes, and H3 (Histone 3) nuclear gene] were sequenced for over 90 species in 20 genera, and the molecular data set was supplemented by studies of radula morphology. Our analysis recovered Mitridae as a monophyletic group, whereas the genus Mitra was found to be polyphyletic. Of 42 mitrid species included in the analysis, 37 formed a well-supported ‘core Mitridae’ consisting of four major clades, three of them consistent with the subfamilies Cylindromitrinae, Imbricariinae, and Mitrinae, and Strigatella paupercula standing out by itself. Basal to the ‘core Mitridae’ are four minor lineages, with the genus Charitodoron recognized as sister group to all other Mitridae. The deep-water family Pyramimitridae shows a sister relationship to the Mitridae, with high support for a Pyramimitridae + Mitridae clade. Our results recover the monophyly of the Costellariidae, which form a well-supported clade that also includes Ptychatractidae, Columbariinae, and Volutomitridae, but not Mitridae. Most derived and diverse amongst Costellariidae are species of Vexillum, characterized by a bow-shaped, multicuspidate rachidian tooth. Several previously unrecognized deep-water costellariid lineages are revealed. Their members retain some plesiomorphies – in particular a tricuspidate rachidian tooth – that makes them morphologically intermediate between ptychatractids and Vexillum. The taxa of Ptychatractidae included in the analysis are not monophyletic, but form three well-supported, unrelated groupings, corresponding respectively to Ceratoxancus + Latiromitra, Exilia, and Exiliodea. None of them shows an affinity to Pseudolividae. © 2015 The Linnean Society of London

Heterogeneous Rates of Molecular Evolution and Diversification Could Explain the Triassic Age Estimate for Angiosperms.

Dating analyses based on molecular data imply that crown angiosperms existed in the Triassic, long before their undisputed appearance in the fossil record in the Early Cretaceous. Following a re-analysis of the age of angiosperms using updated sequences and fossil calibrations, we use a series of simulations to explore the possibility that the older age estimates are a consequence of (i) major shifts in the rate of sequence evolution near the base of the angiosperms and/or (ii) the representative taxon sampling strategy employed in such studies. We show that both of these factors do tend to yield substantially older age estimates. These analyses do not prove that younger age estimates based on the fossil record are correct, but they do suggest caution in accepting the older age estimates obtained using current relaxed-clock methods. Although we have focused here on the angiosperms, we suspect that these results will shed light on dating discrepancies in other major clades.

Qualitative analysis of the vaginal microbiota of healthy cattle and cattle with genital-tract disease.

The microbial community of the reproductive appara-tus, when known, can provide information about the health of the host. Metagenomics has been used to characterize and obtain genetic infor-mation about microbial communities in various environments and can relate certain diseases with changes in this community composition. In this study, samples of vaginal surface mucosal secretions were col-lected from five healthy cows and five cows that showed symptoms of reproductive disorders. Following high-throughput sequencing of the isolated microbial DNA, data were processed using the Mothur soft-ware to remove low-quality sequences and chimeras, and released to the Ribosomal Database Project for classification of operational taxo-nomic units (OTUs). Local BLASTn was performed and results were loaded into the MEGAN program for viewing profiles and taxonomic microbial attributes. The control profile comprised a total of 15 taxa, with Bacteroides, Enterobacteriaceae, and Victivallis comprising the highest representation of OTUs; the reproductive disorder-positive profile comprised 68 taxa, with Bacteroides, Enterobacteriaceae, His-tophilus, Victivallis, Alistipes, and Coriobacteriaceae being the taxa with the most OTU representation. A change was observed in both the community composition as well as in the microbial attributes of the profiles, suggesting that a relationship might exist between the patho-gen and representative taxa, reflecting the production of metabolites to disease progression.

Habitat-dependent diversification and parallel molecular evolution: Water scavenger beetles as a case study

Abstract Habitat shift is a key innovation that has contributed to the extreme diversification of insects. Most groups are well-adapted to more or less specific environments and shifts usually only happen between similar habitats. To colonize a profoundly different habitat type does not only present ecological opportunities but also great challenges. We used Hydrophiloidea (water scavenger beetles) as a system to study transitions between terrestrial and aquatic environments. We estimated the diversification rate of different clades using phylogenetic trees based on a representative taxon sampling and six genes. We also investigated possible evolutionary changes in candidate genes following habitat shifts. Our results suggest that the diversification rate is relatively slow (0.039?0.050 sp/My) in the aquatic lineage, whereas it is distinctly increased in the secondarily terrestrial clade (0.055?0.075 sp/My). Our results also show that aquatic species have a G (Glycine) or S (Serine) amino acid at a given site of COI, while terrestrial species share an A (Alanine) amino acid with terrestrial outgroups. This indicates that habitat factors may create selection pressure on the evolution of functional genes and cause homoplasy in molecular evolution.

Mapping biodiversity hotspots and conservation priorities for the Euro-Mediterranean headwater ecosystems, as inferred from diversity and distribution of a water beetle lineage

Euro-Mediterranean running water ecosystems represent a highly threatened habitat due to draining, construction, agriculture, eutrophication, pollution and climate changes. Thereby, the associated biodiversity is often more threatened compared to any other ecosystem and the identification of biodiversity hotspots and conservation priorities for running water fauna is therefore a primary target. Here we focused on invertebrates, as important indicators of ecosystem functions, modelling a lineage of water beetles and investigating the conservation status of Euro-Mediterranean headwater ecosystems. We selected the “Haenydra” lineage (Hydraenidae, genus Hydraena) as representative taxon (92 species overall, known to occur from Iberian Peninsula to W Iran), analysing a geographic database including literature, field-collecting and Museums data in order to map the distribution of biodiversity hotspots in Euro-Mediterranean headwater systems and locate the running water sites potentially important for invertebrates conservation. We hence assessed the conservation priorities assigning IUCN threat Categories—following IUCN guidelines—to all the species of the lineage, together with a herein introduced Conservation Score (CS) computed using a procedure tailored specifically for water beetles, also analysing historical series. We found that threatened categories (VU or higher), with high CSs, should be assigned to >70 % of the species, suggesting that, considering this lineage a representative model, the headwaters conservation status in Euro-Mediterranean areas is alarming. Cantabria, Pyrenees, Alps and Central Apennines were identified as biodiversity hotspots, whereas the combination of IUCN categories and CSs revealed that the areas with highest conservation concern are distributed in W-Alps, E-Alps, Apennines, Central Spain, Greece and N-Turkey. Our analyses suggested a dramatic worsening of running water ecosystems in several Mediterranean regions and in particular in Italy, Greece and Turkey. The comparison between the IUCN categories and the newly introduced CSs evidenced the importance of taking into account the ecological, hydro-geological and historical features when assessing conservation strategies for running water organisms.