Representative Taxa Research Articles

Relationships between physical and chemical factors and aquatic macroinvertebrates in perennial streams in the arid northern mountain basin El Batinah, Oman

The relationships between physical properties, water chemistry and aquatic macroinvertebrates were investigated in riffles of four perennial streams in the arid northern Oman. Samples were collected monthly in autumn, winter and spring with a Surber net. Thirty two invertebrate taxa were recorded, most species are widely distributed, but few species with very restricted distribution were also captured. Diptera followed by Pulmonata, Coleoptera and Odonata were the most represented taxa, Trichoptera and Heteroptera were a significant component only in one station (the Fezeh), where the lowest mean water temperature (23°C) was recorded. In the dry months from May to October, aquatic macroinvertebrates were completely absent. In order to summarise the community response some biotic indices were calculated. The highest diversity was observed in the Fezeh station. A seasonal gradient was also observed, with the highest diversity values in January, April, and December. The low faunal diversity was attributed to the high air and water temperature and the hydrological regime instability. A between station and a between month coinertia analysis was carried out, to analyse the response to spatial and seasonal factors. The first coinertia axis was correlated with altitude and substrate composition, while the second axis was correlated with air and water temperature. The present research emphasizes the urgency for preserving the less disturbed <em>wadis</em> in arid zones, because, despite their species poorness, their uniqueness in faunal composition requires special attention. The presence of few endemic species with very restricted distribution highlights the topicality and the value in investigating these areas, allowing the increase of our knowledge on biodiversity, ecology and biogeography about the benthic macroinvertebrates living in these extreme habitats.

Concordance of diatom, macroinvertebrate and fish assemblages in streams at nested spatial scales: Implications for ecological integrity

Understanding the concordance among different assemblages as well as their responses to the environmental gradients at multiple spatial scales is an important issue in conservation biology and in the assessment of ecological integrity. We examined the community concordance among diatoms, macroinvertebrates and fish in minimally disturbed streams on four nested spatial scales (i.e., national, catchment, sub-catchment and mountain or lowland at sub-catchment scales) in Korea. The results, based on non-metric multidimensional scaling, showed that diatoms, macroinvertebrates and fish displayed consistent patterns that were strongly structured along an altitude gradient at the national scale. However, the responses to all other influential environmental factors differed by assemblages. The community composition of fish closely reflected the gradients of larger scale environmental factors (i.e., geographical and hydrological variables), whereas macroinvertebrates mainly reflected the changes at relatively finer environmental scales (e.g., hydrological variables and substrate composition). Diatoms showed relatively weak relationships with environmental variables except for the altitudinal gradient. Community concordance based on Protest was significant at four nested spatial scales, although most cases of community concordances were relatively weak. Fish and macroinvertebrates showed high concordance at the national and catchment scales, whereas macroinvertebrates and diatoms showed high concordance at smaller scales (i.e., mountain or lowland at sub-catchment). Finally, our study demonstrated that community concordance among diatoms, macroinvertebrates and fish would be different according to spatial scales and even in the same scales and that use of a representative taxon to assess ecological integrity should be applied with caution.

Phylogeny and age of chromidotilapiine cichlids (Teleostei: Cichlidae)

Chromidotilapiine cichlid fishes (Teleostei: Cichlidae) of West and Central Africa represent the most species rich ancient African cichlid lineage. In contrast to the mega-diverse haplotilapiine cichlids from the African rift valley and crater lakes, very little is known about their phylogenetic history. Based on mitochondrial and nuclear DNA sequences and a representative taxon sampling, we present a first molecular phylogenetic hypothesis and propose age estimates for their origin and diversification. Our data support the monophyly and an Oligocene/Eocene origin of chromidotilapiines. Within chromidotilapiines, two large, reciprocally monophyletic clades are present and the enigmatic genus Teleogramma could be phylogenetically placed for the first time. The two distantly distributed species Limbochromis robertsi and Chromidotilapia schoutedeni were identified as sister group to the Congolian species complexes of Nanochromis and Congochromis. This unexpected phylogenetic link between a region in West Africa and the Congo basin suggests an ancient hydrogeographic corridor spanning almost half of the African continent. The nearly complete taxon sampling, good knowledge on species distribution patterns and well resolved phylogenies allow the presumption that paleogeographic patterns rather than ecological factors shaped the ancient divergence within chromidotilapiines, which predates the origin of the mega-diverse austrotilapiine lineage, comprising the majority of African cichlid species.

Macroinvertebrados aquáticos associados às raízes de Eichhornia azuera (Swarts) Kunth (Pontederiaceae) em uma lagoa marginal no Pantanal, MS

Macrophytes play an important role in the community structure of aquatic systems. In this study, we examined the macroinvertebrate communities within 20 Eichhornia azurea roots in an oxbow lake in Pantanal (MS) during dry season. Species abundance and richness were compared via linear regression, and the mean relative proportion of macroinvertebrates among root samples was determined. Macroinvertebrates were identified to the lowest practical taxonomic level, and root volume was measured using the volume displacement method. We identified 371 specimens, belonging to 31 families and 21 taxonomic groups. Chironomus sp. (Chironomidae), Slavinia sp. and Dero sp. (Naididae), all detritivores, were most the represented taxa. Regression analysis indicated a positive correlation between root volume and the abundance and richness of the macroinvertebrate community. Analysis of variance showed no statistically significant differences between species abundance and richness among different E. azuera root volumes, however we did observe a trend toward a positive correlation of both variables with increasing root volume. We suspect that greater root volumes should increase microhabitat availability, which could explain this observed trend. Our results indicate that E. azurea roots may play an important ecologic role (e.g., by providing shelter, food stock) in lake macroinvertebrate communities.

Climate change effects on animal and plant phylogenetic diversity in southern Africa

AbstractMuch attention has been paid to the effects of climate change on species' range reductions and extinctions. There is however surprisingly little information on how climate change driven threat may impact the tree of life and result in loss of phylogenetic diversity (PD). Some plant families and mammalian orders reveal nonrandom extinction patterns, but many other plant families do not. Do these discrepancies reflect different speciation histories and does climate induced extinction result in the same discrepancies among different groups? Answers to these questions require representative taxon sampling. Here, we combine phylogenetic analyses, species distribution modeling, and climate change projections on two of the largest plant families in the Cape Floristic Region (Proteaceae and Restionaceae), as well as the second most diverse mammalian order in Southern Africa (Chiroptera), and an herbivorous insect genus (Platypleura) in the family Cicadidae to answer this question. We model current and future species distributions to assess species threat levels over the next 70 years, and then compare projected with random PD survival. Results for these animal and plant clades reveal congruence. PD losses are not significantly higher under predicted extinction than under random extinction simulations. So far the evidence suggests that focusing resources on climate threatened species alone may not result in disproportionate benefits for the preservation of evolutionary history.

Flammeopellis bambusicola gen. et. sp. nov. (Polyporales, Basidiomycota) evidenced by morphological characters and phylogenetic analysis

A new poroid wood-inhabiting fungal genus, Flammeopellis, is proposed based on morphological characters and molecular evidence. The genus is typified by Flammeopellis bambusicola sp. nov., which macroscopically is characterized by an annual growth habit and stipitate basidiocarps with a reddish-brown pileal cuticle. Microscopically, it has a dimitic hyphal system with generative hyphae frequently with simple septa, occasionally with clamp connections, strongly dextrinoid and cyanophilous skeletal hyphae, and ellipsoid to drop-shaped, pale yellowish, thick-walled, smooth, weakly dextrinoid and cyanophilous basidiospores. Phylogenetic analysis based on molecular data of ITS+LSU nrRNA gene regions indicates that Flammeopellis belongs to the core polyporoid clade and is closely related to Perenniporiella. Combined ITS+nLSU+mtSSU+TEF1 sequence data of representative taxa in Perenniporia sensu lato demonstrated that Flammeopellis bambusicola grouped with the Perenniporiella clade, but formed a monophyletic lineage with a strong support (100 % BP, 1.00 BPP). The morphological and molecular evidence confirmed the placement of the new genus in the core polyporoid clade and established its relationships with similar genera.

The Effects of Ocean Acidity and Elevated Temperature on Bacterioplankton Community Structure and Metabolism

By the end of the 21st century, mean sea surface temperatures are expected to increase 4?C, while atmospheric CO2 concentrations are predicted to triple causing seawater to become acidic. These compounding effects will undoubtedly have major consequences for the organisms and processes in the oceans. Bacterioplankton play a vital role in the marine carbon cycle and the oceans’ ability to sequester CO2. We utilized pCO2 perturbation experiments to investigate the effects of ocean acidity and elevated temperature on bacterioplankton community structure and metabolism. Terminal-restriction fragment length polymorphism (T-RFLP) of small subunit ribosomal (SSU) genes revealed that bacterioplankton incubated in lower pH conditions exhibited a reduction of species richness, evenness, and overall diversity, relative to those incubated in ambient pH conditions. Non-metric multidimensional scaling (MDS) of T-RFLP data resulted in clustering by pH suggesting that pH influenced the structure of these communities. Shifts in the dominant members of bacterioplankton communities incubated under different pH were observed in both T-RFLP and SSU clone library analyses. Both ambient and low pH communities were dominated by Gammaproteobacteria and Alphaproteobacteria, although abundance of Alphaproteobacteria increased in communities incubated at lower pH. This was expressed by the gamma to alpha ratio dropping from ~9 to 4, respectively. In general, the representative taxa from these two classes were distinctly different between the treatments, with a few taxa found to be persistent in both treatments. Changes in the structure of bacterioplankton communities coincided with significant changes to their overall metabolism. Bacterial production rates decreased, while bacterial respiration increased under lower pH conditions. This study highlights the ability of bacterioplankton communities to respond to ocean acidification both structurally and metabolically, which may have significant implications for their ecological function in the marine carbon cycle and the ocean’s response to global climate change.

The dynamic proliferation of CanSINEs mirrors the complex evolution of Feliforms.

BackgroundRepetitive short interspersed elements (SINEs) are retrotransposons ubiquitous in mammalian genomes and are highly informative markers to identify species and phylogenetic associations. Of these, SINEs unique to the order Carnivora (CanSINEs) yield novel insights on genome evolution in domestic dogs and cats, but less is known about their role in related carnivores. In particular, genome-wide assessment of CanSINE evolution has yet to be completed across the Feliformia (cat-like) suborder of Carnivora. Within Feliformia, the cat family Felidae is composed of 37 species and numerous subspecies organized into eight monophyletic lineages that likely arose 10 million years ago. Using the Felidae family as a reference phylogeny, along with representative taxa from other families of Feliformia, the origin, proliferation and evolution of CanSINEs within the suborder were assessed.ResultsWe identified 93 novel intergenic CanSINE loci in Feliformia. Sequence analyses separated Feliform CanSINEs into two subfamilies, each characterized by distinct RNA polymerase binding motifs and phylogenetic associations. Subfamily I CanSINEs arose early within Feliformia but are no longer under active proliferation. Subfamily II loci are more recent, exclusive to Felidae and show evidence for adaptation to extant RNA polymerase activity. Further, presence/absence distributions of CanSINE loci are largely congruent with taxonomic expectations within Feliformia and the less resolved nodes in the Felidae reference phylogeny present equally ambiguous CanSINE data. SINEs are thought to be nearly impervious to excision from the genome. However, we observed a nearly complete excision of a CanSINEs locus in puma (Puma concolor). In addition, we found that CanSINE proliferation in Felidae frequently targeted existing CanSINE loci for insertion sites, resulting in tandem arrays.ConclusionsWe demonstrate the existence of at least two SINE families within the Feliformia suborder, one of which is actively involved in insertional mutagenesis. We find SINEs are powerful markers of speciation and conclude that the few inconsistencies with expected patterns of speciation likely represent incomplete lineage sorting, species hybridization and SINE-mediated genome rearrangement.

Plastid and mitochondrion genomic sequences from Arctic Chlorella sp. ArM0029B.

BackgroundChorella is the representative taxon of Chlorellales in Trebouxiophyceae, and its chloroplast (cp) genomic information has been thought to depend only on studies concerning Chlorella vulgaris and GenBank information of C. variablis. Mitochondrial (mt) genomic information regarding Chlorella is currently unavailable. To elucidate the evolution of organelle genomes and genetic information of Chlorella, we have sequenced and characterized the cp and mt genomes of Arctic Chlorella sp. ArM0029B.ResultsThe 119,989-bp cp genome lacking inverted repeats and 65,049-bp mt genome were sequenced. The ArM0029B cp genome contains 114 conserved genes, including 32 tRNA genes, 3 rRNA genes, and 79 genes encoding proteins. Chlorella cp genomes are highly rearranged except for a Chlorella-specific six-gene cluster, and the ArM0029B plastid resembles that of Chlorella variabilis except for a 15-kb gene cluster inversion. In the mt genome, 62 conserved genes, including 27 tRNA genes, 3 rRNA genes, and 32 genes encoding proteins were determined. The mt genome of ArM0029B is similar to that of the non-photosynthetic species Prototheca and Heicosporidium. The ArM0029B mt genome contains a group I intron, with an ORF containing two LAGLIDADG motifs, in cox1. The intronic ORF is shared by C. vulgaris and Prototheca. The phylogeny of the plastid genome reveals that ArM0029B showed a close relationship of Chlorella to Parachlorella and Oocystis within Chlorellales. The distribution of the cox1 intron at 721 support membership in the order Chlorellales. Mitochondrial phylogenomic analyses, however, indicated that ArM0029B shows a greater affinity to MX-AZ01 and Coccomyxa than to the Helicosporidium-Prototheca clade, although the detailed phylogenetic relationships among the three taxa remain to be resolved.ConclusionsThe plastid genome of ArM0029B is similar to that of C. variabilis. The mt sequence of ArM0029B is the first genome to be reported for Chlorella. Chloroplast genome phylogeny supports monophyly of the seven investigated members of Chlorellales. The presence of the cox1 intron at 721 in all four investigated Chlorellales taxa indicates that the cox1 intron had been introduced in early Chorellales as a cis-splice form and that the cis-splicing intron was inherited to recent Chlorellales and was recently trans-spliced in Helicosporidium.

Analysis of DNA from Feces to Identify Prey of Big Brown Bats (Eptesicus fuscus) Caught in Apple Orchards

We isolated, amplified, and sequenced the mtDNA from insect fragments found in the feces of big brown bats (Eptesicus fuscus) caught in apple orchards, to determine whether the bats were consuming prey of economic interest, especially common pests of apples. Comparison of sequences to those in a reference database (Barcode of Life Database) allowed identification of 58 sequences from 40 bats to the level of family, genus, or species; 40 (69%) of the 58 sequences of insects matched to species, 6 (10%) to only genus, and 12 (21%) to only family. Forty-nine (84%) of the 58 matches, from 34 (85%) of the 40 bats, were to taxa within the order Coleoptera and most represented taxa within the family Carabidae; other orders included Diptera, Ephemeroptera, and Hymenoptera. Eighteen different species were identified, including several important pests, such as various mosquitoes (Aedes), the spotted cucumber beetle (Diabrotica undecimpunctata), and pavement ants (Tetramorium caespitum), although no pests specific to apples were discovered.

Representative taxa in field trials for environmental risk assessment of genetically modified maize

When assessing the benefits and risks of transgenic crops, one consideration is their relative effects on non-target arthropod (NTA) abundance and functions within agroecosystems. Several laboratory and field trials have been conducted in Spain since the late 1990s to assess this issue. A consideration in the design of field trials is whether it is necessary to sample most NTAs living in the crop or only representative taxa that perform main ecological functions and have a good capacity to detect small changes in their abundance. Small changes in the field abundance of an effective representative taxon should be detectable using standard experimental protocols. The ability of a species to reveal differences across treatments may be analysed by examining the detectable treatment effects for surveyed non-target organisms. Analysis of data from several NTAs recorded in 14 field trials conducted over 10 years using complete block designs allowed us to select a number of representative taxa capable of detecting changes in the density or activity of arthropod herbivores, predators, parasitoids and decomposers in transgenic and non-transgenic maize varieties. The most suitable NTA as representative taxa (with detectable treatment effects below 50%) included leafhoppers among arthropod herbivores, Orius spp., Araneae, and Carabidae among predators, chalcidids, particularly the family Mymaridae, among parasitoids and Chloropidae as decomposer. Details of sampling techniques for each sampled taxa and their advantages and disadvantages are discussed. It is concluded that abundance of taxa is the most influential factor determining their capacity to detect changes caused by genetically modified varieties.

Self-organizing map and species abundance distribution of stream benthic macroinvertebrates in revealing community patterns in different seasons

Benthic macroinvertebrates are considered to be one of the most representative taxa in assessing the ecological integrity of aquatic ecosystems. Data for benthic macroinvertebrates collected using the Surber sampler were used for analysis at different sampling sites across different levels of pollution. Species Abundance Distribution (SAD) and Self-Organizing Map (SOM) were utilized in combination to reveal both consistency and variability in community compositions under natural and anthropogenic conditions. According to the SOM benthic macroinvertebrates were clustered in different season groups (e.g., “summer”, “autumn–winter”) at the less polluted site. SADs of the sampled communities, however, were overall stable across different seasons except the period from late spring to summer (i.e., low level of abundance for the mid-ranked species in SADs) due to heavy rainfall in the Monsoon climate. Along with increase in degree of pollution, seasonality deceased for both SOMs and SADs. In all seasons, the SAD curves were fitted to a lognormal distribution for the less polluted site while the polluted site was in accordance with a geometric series. The parameters in the SAD models were not significantly different across different seasons. Species in the highest ranks in the SADs were persistently dominant regardless of seasons, while densities of the mid-ranked species were variable in different seasons at the less and intermediately polluted sites. At the severely polluted site a few selected tolerant species showed high densities persistently and variability of densities in different seasons was minimized. Species groups clustered using the SOM also presented stronger persistence in SADs, and were feasible in addressing diverse patterns of species composition and in outlining species associations presented in different sampling sites through ordination and clustering. The combined use of SOM and SAD is highly be suitable in presenting community properties and ecological integrity in stream ecosystems in response to natural variability and anthropogenic disturbances.

Convolvulus L. (Convolvulaceae) - A New Generic Record to Kerala

Convolvulus L. is newly recorded for Kerala with Convolvulus arvensis L., as the representative taxon.

Molecular evidence for the origin and evolutionary history of the rare American desert monotypic family Setchellanthaceae

Setchellanthus caeruleus, which has disjunct populations in the north of the Chihuahuan Desert and in the Tehuacan-Cuicatlan valley, was selected to understand the evolutionary history of plants in this desert and its southerly relicts. This species constitutes the monotypic family Setchellanthaceae, which forms part of a group of plants that produce mustard-oil glucosides or glucosinolates. Molecular phylogenetic analyses based on DNA plastid sequences of plants of S. caeruleus from both areas, including representative taxa of the order Brassicales, were carried out to estimate the time of origin of the family (based on matK + rcbL) and divergence of populations (based on psbI-K, trnh-psbA, trnL-trnF). In addition, comparative ecological niche modelling was performed to detect if climate variables vary significantly in northern and southern populations. Analyses revealed that Setchellanthaceae is an ancient lineage that originated between 78 and 112 Mya during the mid-late Cretaceous—much earlier than the formation of the Chihuahuan Desert. The molecular data matrix displayed a few indel events as the only differences of plastid DNA sequences between northern and southern populations. It is suggested that due to climate changes in this desert in the Pliocene, populations of Setchellanthus remained in the Sierra de Jimulco and in Cuicatlan, in climatically stable locations. Ecological niche models of northern populations predict niches of southern populations and identity niche tests indicate that there are no differences in their ecological niches.

Micro-computed tomography: Introducing new dimensions to taxonomy

Continuous improvements in the resolution of three-dimensional imaging have led to an increased application of these techniques in conventional taxonomic research in recent years. Coupled with an ever increasing research effort in cybertaxonomy, three-dimensional imaging could give a boost to the development of virtual specimen collections, allowing rapid and simultaneous access to accurate virtual representations of type material. This paper explores the potential of micro-computed tomography (X-ray micro-tomography), a non-destructive three-dimensional imaging technique based on mapping X-ray attenuation in the scanned object, for supporting research in systematics and taxonomy. The subsequent use of these data as virtual type material, so-called “cybertypes”, and the creation of virtual collections lie at the core of this potential. Sample preparation, image acquisition, data processing and presentation of results are demonstrated using polychaetes (bristle worms), a representative taxon of macro-invertebrates, as a study object. Effects of the technique on the morphological, anatomical and molecular identity of the specimens are investigated. The paper evaluates the results and discusses the potential and the limitations of the technique for creating cybertypes. It also discusses the challenges that the community might face to establish virtual collections. Potential future applications of three-dimensional information in taxonomic research are outlined, including an outlook to new ways of producing, disseminating and publishing taxonomic information.

Trophic niche and feeding biology of the Italian wall lizard, Podarcis siculus campestris (De Betta, 1857) along western Mediterranean coast

Trophic niche of the Italian wall lizard was studied at three different sites in Tuscany (central northern Ita- ly), two along the Mediterranean sea, one inland. Fecal pellet analysis was carried out on 71 pellets (37 of male and 34 of female adult lizards), accounting on the whole for 184 prey items. Coleoptera, Hymenoptera (ants), Araneae and Gastropoda were the most represented taxa (numerical abundance of ca 22, 7, 7, 6% respectively). We found Brillouin diversity index similar in females and in males, with a marked overlap between sexes, but differences in niche overlap- ping among localities. Diet spectrum was quite different with that found in other central Italy localities, in the Tuscan Archipelago, or in areas where P. siculus has recently introduced. Our study confirms the opportunistic pattern and adaptability of this lizard species, and increases the range of sampled localities within the species' range.

Molecular Phylogeny and Redefined Generic Limits of <I>Calathea</I> (Marantaceae)

Calathea, with an estimated 285 species, is the largest genus of Marantaceae and an important component of Neotropical herbaceous diversity. The genus is also of high importance for horticulture as species are cultivated for their showy, patterned leaves. Previous molecular phylogenetic studies indicated that the genus is polyphyletic, but have not provided a basis for redefining generic limits due to incomplete taxon sampling. To address this problem we analyzed DNA sequence data from three plastid markers (matK with flanking 30 trnK intron, trnL intron and trnL-trnF intergenic spacer) and one nuclear marker (ITS) under a maximum parsimony criterion for a large and representative taxon sample covering all previously proposed infrageneric entities, and representing the full range of morphological variation known in the genus. Our results confirm that Calathea is polyphyletic. One clade, including subgenus Calathea ,t heC. lanicaulis group, and the genus Sanblasia, is sister to a clade formed by Ischnosiphon and Pleiostachya .T he genusMonotagma is placed as sister to this clade. The remaining species form a second strongly supported clade as sister to a clade containing these other genera. Based on these findings Calathea is recircumscribed in a narrow sense and Sanblasia is placed in synonymy. The genus Goeppertia is resurrected and redefined to include all members of the second Calathea clade. Morphological characters defining each genus are provided. A total of 246 new combinations are made. Keywords—Goeppertia, ITS, matK, maximum parsimony, Sanblasia, trnL-F region. Marantaceae, with approximately 550 species, is the sec- ond largest family in the Zingiberales. The family is particu- larly diverse in the Neotropics where it is represented by an estimated 450 species. Phylogenetic studies at the family level (Andersson and Chase 2001; Prince and Kress 2006a) have shown Neotropical diversity to primarily involve two large groups: the Maranta clade with nine genera and ca. 70 species is concentrated in southeastern Brazil; and the Calathea clade with five genera and ca. 370 species is distrib- uted throughout the Neotropics but with highest diversity in northwestern South America. Within the Calathea clade, Calathea G. Mey. is by far the largest genus with an esti- mated 300 species (Andersson 1998). Govaerts and Kennedy (2012) list 285 accepted names. These numbers clearly make Calathea the largest genus in the family. The genus is also important for horticulture as indoor plants and in tropical garden landscaping due to their variegated leaves with spots or bands of white, orange, or red, and often bright purple underside. Several species have been used as model organisms for studies of reproductive ecology, plant phys- iology, and demography (e.g. Kennedy 1978; Horvitz and Schemske 2002; Clasen-Bockhoff and Heller 2008; Matlaga and Sternberg, 2009; Swenson 2009; Maron et al. 2010). Other

Chromosome counts in wild and cultivated species of Abelmoschus Medikus. from the Indian sub-continent

SummaryAbelmoschus is regarded as a polyploid-polyspecies complex and a genus with variable genome organisation and resultant ambiguity in its speciation. A cytogenetic basis for taxonomy can be significant, due to the fact that many of the taxonomic units of Abelmoschus are heterogeneous in nature with deviant numbers of chromosomes. In the present investigation, 39 wild and cultivated accessions of Abelmoschus from India, belonging to three representative taxa, were used to record clear and authentic chromosome counts. From these data, the numbers of somatic chromosomes in A. angulosus var. grandiflorus, A. moschatus ssp. moschatus, and A. moschatus ssp. tuberosus are reported to be 2n = 66, 2n = 72, and 2n = 72, respectively. The present study also confirmed 2n = 130 to be the authentic number of somatic chromosomes in A. esculentus. Earlier conflicting reports are ruled out. Reports of the occurrence of cytotypes in A. esculentus are not acceptable, due to its wide area of cultivation.

Faune corallienne des récifs toarciens du Moyen Atlas marocain, première approche

Abstract Des récifs ont été décrits dans le Toarcien supérieur du Moyen Atlas Marocain [Elmi et al., 2002]. Ils sont localisés dans le synclinal de Awragh-Afennourir (Moyen Atlas occidental) immédiatement au sud du Moyen Atlas tabulaire. Ce sont des biohermes placés au sommet de blocs basculés. Leur épaisseur varie de 1 à 12 m. Ils reposent sur une formation datée de la zone à Levisoni, sous zone à Gemma et sont couverts par des sédiments appartenant à la partie supérieure de la zone à Meneghini. Leur paléolatitude était de 18°N. Un ensemble de 18 échantillons de coraux collectés par S. Elmi sont ici analysés. Ils constituent un témoignage exceptionnel de faune corallienne récifale pour cet étage. Les taxons appartenant aux genres Cladophyllia, Diplocoenia ?, Montlivaltia (deux espèces), Thecosmilia (deux espèces), Isastrea ?, Latomeandra, Periseris, Microphyllia (trois espèces), et Proleptophyllia (deux espèces), ont été identifiés. La faune inclut 12 formes coloniales et 7 solitaires. Parmi les spécimens coloniaux, les formes méandroïdes avec un haut niveau d’intégration colonial sont bien représentées et fournissent un argument fort pour la présence de zooxanthelles symbiotiques. L’examen des textures micritiques et des croûtes microbialitiques, associé avec le développement important des microarchitectures pennulaires suggèrent un récif sous le niveau d’action des vagues de beau temps et des eaux plutôt mésotrophiques. Les coraux, leur forme et leur diversité, permettent de diagnostiquer des récifs de zone photique, à une profondeur et une latitude optimale. Les extensions stratigraphiques de plusieurs genres sont agrandies : nouvelle première occurrence pour Cladophyllia, Latomeandra et Periseris (peut être aussi Diplocoenia) et nouvelle dernière occurrence pour Proleptophyllia classiquement considéré comme Pliensbachien. La seule monographie disponible à caractère général sur les coraux du Lias du Maroc [Beauvais, 1986] identifie 15 taxons génériques pour le Toarcien. Tous proviennent du Haut Atlas et seulement 3 taxons sont communs avec les résultats présentés ici. La vue générale est celle d’une faune qui ressemble davantage à celle des communautés récifales du Dogger qu’à celle du Pliensbachien.

Biodiversidade e estrutura da comunidade zooplanctônica na Sub-bacia Hidrográfica do Rio Poxim, Sergipe, Brasil

The zooplankton of aquatic environments is composed mostly of protozoans, rotifers, cladocerans and copepods, which play an important role in the food chain, transferring mass and energy from primary producers to higher trophic levels. This work was prepared with the objective of contributing to the knowledge of zooplankton biodiversity that occurs in the Sub-basin of Rio Poxim. Water samples were taken at monthly intervals at four sampling stations located along the sub-basin in the period August 2009 to July 2010. To obtain the zooplankton community, 100 L of water were filtered on nylon net with an aperture of 50 mm. Were identified 72 taxa distributed in the following taxonomic categories Rotifera, Protozoa, Porifera, Nematoda, Anellida, Cladocera, Copepoda, Ostracoda, Isopoda and Insecta. In terms of species richness, the phylum Rotifera followed by the Protoctista were the most relevant with forty and fifteen taxa, respectively. The most representative taxa in numerical terms were Arcella vulgaris, Notholca sp. Rotary sp. and nematodes. Regarding the community diversity index, the community was characterized as low diversity, but the taxa were distributed evenly in all monitoring points.