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The objective of this paper is to resolve the taxonomic complex formed by G. neesii, G. martii, their infraspecific taxa, and other similar species, totaling eight names. This group grows from southern Uruguay to northeastern Brazil, and the morphology of individuals gradually changes along this latitudinal gradient, making it possible to identify many morphotypes that have been assigned by previous authors either as species or varieties. We combined ecological and morphometrical approaches to increase the resolution within this complex. We used two techniques of cluster analysis within the ecological data to find the correct number of clusters in the data set. The significant groups found by cluster analysis were then tested a posteriori with a permuted MANOVA to discover congruent morphological groups. Our results showed that from the eight previously hypothesized groups, only two were both ecologically and morphologically significant and could represent separately evolving lineages. The necessary nomenclatural changes as well as a short taxonomic description of the taxa are provided in this paper. [ABSTRACT FROM AUTHOR]

This paper documents the first record of Furipterus horrens (F. Cuvier 1828) from the state of Paraíba, in northeastern Brazil. A female specimen was collected in a rock shelter located in a legal reserve (614 ha) of Caatinga habitat. The morphometric data and morphological characters were consistent with those recorded for the species at other Brazilian sites. The present record increases to 67 the total number of bats species known to occur in Paraíba, of which, 40 occur in the Caatinga, and 17 are so far restricted to this biome. [ABSTRACT FROM AUTHOR]

This paper describes a new diatom species, Aulacoseira calypsi Tremarin, Torgan & Ludwig, from specimens in plankton samples from Água Preta lake. This Amazonian lake is a shallow mesotrophic environment situated in northern Brazil. The species is characterized by long filaments united by spatulate linking spines, obovate to conic separation spines, a valve surface variably ornamented, straight striae on the mantle, a narrow ringleist, and one row of sessile rimoportulae near the ringleist. Aulacoseira calypsi's morphometric features are compared with the following similar species: Aulacoseira nygaardii ( Camburn) Camburn & Charles, Aulacoseira lacustris ( Grunow) Krammer, Aulacoseira coroniformis Pearce & Cremer, Aulacoseira occulta Siver & Hamilton, Aulacoseira lancea Siver & Hamilton , Aulacoseira gessneri ( Hustedt) Simonsen, and Aulacoseira islandica ( Müller) Simonsen. The species shares similarities as to frustule size, striation pattern, and narrowness of ringleist; but differs in the morphology of separation and linking spines, and the number and position of the rimoportulae. [ABSTRACT FROM AUTHOR]

The Araguaia Plain has extensive areas of savannah scattered forest fragments similar to circular depressions. These features, in addition to serving as corridors, could be associated with important features such as karsts, closed-water connection structures and ecological-type formations. To identify this relationship and contribute to the understanding of its genesis, this study has as its main objective the morphometric analysis of doliniform functions in the Araguaia Plain. Through the geoenvironmental characterization of the study area; digital facility models -- SRTM; interpretation of Sentinel 2-A satellite images from 2019 to 2020; and calculation of morphometric variables: area, perimeters, activity, altitude, length and density, Kernel circularity index. A total of 24,023 doliniform features associated with green/healthy vegetation were identified in a Coverage Area of 114,900 km², Concentrated Majoritariate in the Brazilian municipalities of Lagoa da Confusão -Tocantins; Pium-Tocantins and Cocalinho-Mato Grosso. The features showed circular superiority areas up to 10 km², circular activity indexes at 0.5 and up to 1 and 1.5, indicating a predominance of circular shapes on slopes of 3% in the NE orientation. Based on the results, it can be verified that these features present sinkholes, as they may be under the influence of patterns associated with some processes, denoting in some processes the existence of a covered karst. [ABSTRACT FROM AUTHOR]

Lavareda decraemerae gen. n., sp. n. is characterised by a cheilostom with a sclerotised ring bearing six anterior projections, a funnel-shaped to tubular stegostom, a large unispiral amphid with wide groove and males with a single precloacal setiform sensillum and 19 tubular supplements in a continuous series. The new species is similar to Cricolaimus coronatus in having the cheilostom consisting of a cuticularised ring with anterior projections. Re-examination of C. elongatus revealed clear differences to the new species, the former showing a bilateral symmetry anteriorly with a lateral axis: the lips are merged into one large dorsal and one large ventral lip with elongated inner and outer labial sensilla and the cheilostom has a cuticularised oblique ring, higher dorsally and ventrally than laterally, with two anteriorly directed claw-like projections, one mid-dorsal and one mid-ventral, whereas the new species has a radial symmetry with low lips with inner and outer labial papillae indistinct and a cheilostom with a cuticularised ring with six anteriorly directed projections, thereby justifying the proposal of Lavareda gen. n. to accommodate the new species from Brazil and L. coronatus comb. n. (= C. coronatus). An emended diagnosis of Cricolaimus is given. This is the first record of a species belonging to the Rhadinematidae colonising an artificial substrate. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Water that evaporates from reservoirs can be considered water lost by the system. To estimate the volume of water evaporated from a reservoir, the climate and reservoir morphometric factors should be considered. The model developed by this research estimated the annual evaporation volume rate (EVR) of reservoirs through morphometric factors, based on reservoir maximum volume, maximum depth, and maximum area. In the study area, located in a semi-arid region of Brazil, 5–88% of reservoir maximum volumes were determined to be lost annually during the evaporation process. The results of the model adjustment were considered good since the model did not take into account climatic factors and uses only easily obtained morphometric data. The model developed is a new, easy-to-use tool for predicting the evaporation efficiency of reservoirs and can be used for planning new dam projects and assessing the operation of those already installed. The model was developed for reservoirs in the Brazilian semi-arid region, and we recommend building on this methodology for estimating the annual EVR for regions with other specific climates. [ABSTRACT FROM AUTHOR]

The plateaus surrounding the Pantanal in Mato Grosso do Sul are highly threatened by land-use conversion and are home to Ameerega berohoka and Ameerega picta, two species of poison frogs renowned for their aposematic coloration and toxic skin. The species have diurnal and terrestrial habitats and are often observed among dead tree branches, leaf litter or under rocks. Herein, we investigated the diet and sexual dimorphism of body size in A. berohoka and A. picta, aiming to increase our understanding of the natural history of both species. We collected A. berohoka specimens from the Bonito municipality and A. picta from the Rio Negro Municipality and obtained 1,600 prey items organized into 12 categories. We found that formicid insects had the highest index of relative importance and were the most frequent prey category for both species. Despite prey items such as Acari and Isoptera being present in the diet of these species, the niche breadth of these species was low. We found no evidence of sexual dimorphism in body size or body shape for A. berohoka and A. picta. Based on our findings, we conclude that both species are ant specialists, as proposed for other Ameerega species. [ABSTRACT FROM AUTHOR]

The Neotropical catfish genus Kronichthys contains three species distributed along coastal rivers of southern and southeastern Brazil. Although phylogenetic hypotheses are available, the molecular and morphological diversity and species boundaries within the genus remain unexplored. In this study, the authors generated mitochondrial data for 90 specimens combined with morphometric and meristic data to investigate species diversity, species boundaries and putative morphological signatures in Kronichthys. Phylogenetic and species delimitation results clearly show the presence of four genetic lineages, three within Kronichthys heylandi along the coast from Rio de Janeiro to southern São Paulo and a single lineage encompassing both the nominal species Kronichthys lacerta and Kronichthys subteres from the Ribeira de Iguape basin to Santa Catarina in southern Brazil. Nonetheless, morphological data show overlapped ranges in morphometrics and a definition of only two morphotypes, with clear phenotypic differences in the teeth number: K. heylandi differs from K. subteres + K. lacerta by the higher number of premaxillary teeth (30–52 vs. 19–28) and higher number of dentary teeth (28–54 vs. 17–28). Headwater captures and connections of paleodrainages because of sea‐level fluctuations represent the two major biogeographic processes promoting species diversification and lineage dispersal of Kronichthys in the Atlantic coastal range of Brazil. [ABSTRACT FROM AUTHOR]

Copyright of Rodriguésia is the property of Revista Rodriguesia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We present a new assessment of the genetic and morphological variation within Oxymycterus quaestor Thomas, 1903, which currently includes the junior synonyms O. judex Thomas, 1909 and O. misionalis Sanborn, 1931. We integrate distinct lines of evidence, including variation of mitochondrial (Cytochrome b [ Cytb ]) and nuclear (intron 7 of beta fibrinogen gene [ Fgb ]) sequences, and the assessment of skull quantitative traits based on geometric morphometrics, throughout the Atlantic Forest of Southeastern-Southern Brazil, Argentina, and Paraguay. Phylogenetic relationships based on Cytb indicate that O. quaestor is structured in four well-supported clades (lineages A–D), one of them (lineage C) including topotypes of a previously associated nominal form (O. judex). However, these Cytb lineages exhibit lower levels of differentiation based on the Fgb locus, and are not recovered in the genealogies of this nuclear marker, representing a case of mitonuclear discordance. The Cytb lineages also broadly overlapped in the morphospace both in skull shape and size, which sustain the current wider concept of O. quaestor as one single young species (0.947 Myr) that is recently expanding, and ultimately branching out, in the Atlantic Forest. [ABSTRACT FROM AUTHOR]

Integrative approaches are particularly useful to resolve taxonomic uncertainties in species-rich groups that have undergone explosive radiation, such as Hypostomini (suckermouth armored catfishes). This tribe encompasses the genera Hypostomus and Pterygoplichthys, but the actual number of species in each genus and the intergeneric interrelationships are confusing or unknown for some ecoregions in the Neotropics. Here, we analyzed three endemic species Hypostomus chrysostiktos, H. jaguar and H. unae from Northeastern Mata Atlântica in northeastern Brazil based on meristic characters, geometric morphometrics, chromosomal data, DNA barcode and species delimitation algorithms. The current taxonomic status of these catfishes is challenged. While H. unae and H. jaguar revealed a close evolutionary relationship similar to those observed within Hypostomus from other basins, H. chrysostiktos was herein more closely related to Pterygoplichthys, being invariably recovered as a highly distinctive taxonomic unit than to Hypostomus. Therefore, we recommend the reallocation of H. chrysostiktos as Pterygoplichthys chrysostiktos and a thorough systematic review of Pterygoplichthys, particularly focusing on putative convergence traits in relation to Hypostomus. [ABSTRACT FROM AUTHOR]

We describe a new species of the genus Fritziana, historically identified as Fritziana fissilis or F. aff. fissilis. Using adult and tadpole morphology, as well as molecular analyses, we found the new species to be characterized by having the following traits: a mucronate snout tip, a black stripe on the wrist, round subarticular tubercles on the fingers and toes, a closed dorsal egg-pouch in females, tadpoles deposited in bromeliads, and a different mitochondrial transfer RNA gene order, when compared to the general orders already recognized for anurans. This new species occurs in the Atlantic Forest of Brazil, in the states of São Paulo, Parana, Santa Catarina, and Rio Grande do Sul, and has the largest geographic distribution recorded for a species of Fritziana. [ABSTRACT FROM AUTHOR]

Body condition is an important ecological attribute that can provide a measure of the energy stored by an animal or population. Body condition is traditionally ascertained with morphometric body condition indices (BCIs), but some researchers have used various physiological and biochemical parameters as predictors of body condition. This study aimed to test reliable biochemical predictors of body condition in individuals of Neopelma pallescens (Lafresnaye, 1853), found in an Atlantic forest patch. For this purpose we examined the relationship between body condition and the concentrations of blood glucose and ketones. We also verified correlations between blood metabolite concentrations and ecological variables, including time of day, seasons, breeding periods, and ectoparasite infestation. Birds were captured with mist nets at Reserva Biológica de Guaribas, state of Paraíba, Brazil. Blood samples were analyzed with a portable glucometer. The correlation between glucose and ketones was negative. Both metabolites showed significant variations according to time of day. Glucose levels were higher in the afternoon and ketones levels were higher in the morning, suggesting a correlation with daily food intake. The BCI of non-breeding birds was negatively correlated with glucose concentrations. However, the correlation between glucose and the BCI of incubating birds was a positive. Ketone bodies did not correlate with body condition. In relation to ectoparasite infestation, only ketones showed significant results, presenting a higher concentration in infested individuals. Glucose is a good predictor of the BCI of incubating birds since it correlates positively with it. However, the lack of seasonal variations in metabolites indicates that the nutritional status of tropical birds does not change when food is abundant. Thus, we conclude that glucose and ketone bodies can predict the nutritional status of birds but in a context-dependent fashion. [ABSTRACT FROM AUTHOR]

Background: With field releases starting in Brazil, particular interest must be given to understanding how the endosymbiotic bacterium Wolbachia pipientis affects Aedes aegypti mosquitoes with a Brazilian genetic background. Currently, there is limited information on how the bacterium affects phenotypic traits such as larval development rate, metabolic reserves and morphometric parameters in Ae. aegypti. Here, we analyze for the first time, the effect of Wolbachia on these key phenotypes and consider how this might impact the potential of the bacterium as a disease control agent in Brazil. Methods: We examined the influence of the wMel strain of Wolbachia in laboratory Ae. aegypti with a Brazilian genetic background, reared under different larval densities. Pupae formation was counted daily to assess differences in development rates. Levels of metabolic reserves and morphometric parameters were assessed in adults resulting from each larval condition. Results: wMel infection led to more rapid larval development at higher densities for both males and females, with no effect under less crowded conditions in females. Infection also led to reduced body size at both high and low density, but not at intermediate density, although the scale of this difference was maintained regardless of larval density, in comparison to uninfected individuals. Wing shape also varied significantly between infected and uninfected mosquitoes due to larval density. Glycogen levels in uninfected mosquitoes decreased under higher larval density, but were consistently high with Wolbachia infection, regardless of larval density. Conclusions: We demonstrate that the wMel Wolbachia strain can positively influence some important host fitness traits, and that this interaction is directly linked to the conditions in which the host is reared. Combined with previously published data, these results suggest that this Wolbachia strain could be successfully used as part of the Eliminate Dengue Program in Brazil. [ABSTRACT FROM AUTHOR]

Lake Palmas (A = 10.3 km2) is located in the Lower Doce River Valley (LDRV), on the southeastern coast of Brazil. The Lake District of the LDRV includes 90 lakes, whose basic geomorphology is associated with the alluvial valleys of the Barreiras Formation (Cenozoic, Neogene) and with the Holocene coastal plain. This study aimed to investigate the relationship of morphometry and thermal pattern of a LDRV deep lake, Lake Palmas. A bathymetric survey carried out in 2011 and the analysis of hydrographic and wind data with a geographic information system allowed the calculation of several metrics of lake morphometry. The vertical profiling of physical and chemical variables in the water column during the wet/warm and dry/mild cold seasons of 2011 to 2013 has furnished a better understanding of the influence of the lake morphometry on its structure and function. The overdeepened basin has a subrectangular elongated shape and is aligned in a NW-SE direction in an alluvial valley with a maximum depth (Zmax) of 50.7 m, a volume of 2.2×108 m3 (0.22 km3) and a mean depth (Zmv) of 21.4 m. These metrics suggest Lake Palmas as the deepest natural lake in Brazil. Water column profiling has indicated strong physical and chemical stratification during the wet/warm season, with a hypoxic/anoxic layer occupying one-half of the lake volume. The warm monomictic pattern of Lake Palmas, which is in an accordance to deep tropical lakes, is determined by water column mixing during the dry and mild cold season, especially under the influence of a high effective fetch associated with the incidence of cold fronts. Lake Palmas has a very long theoretical retention time, with a mean of 19.4 years. The changes observed in the hydrological flows of the tributary rivers may disturb the ecological resilience of Lake Palmas. [ABSTRACT FROM AUTHOR]

In the Campos Basin, 12 species ofSabatieriawere collected, 2 of which were new to science.Sabatieria labiumsp. nov. is characterized by well-defined lips and a spiral amphideal fovea with 4.25–4.5 narrow turns, combined with cephalic setae 3 µm long and 7–8 small, pore-shaped supplements, gradually spaced further apart anteriorly.Sabatieria verterissp. nov. possesses 8–10 minute, pore-shaped precloacal supplements, gradually spaced further apart anteriorly, and short, slightly sclerotized spicules. Additionally, redescriptions ofSabatieria flecha,S. fidelis,S. mortenseni,S. ornataandS. paracupidaare presented. The collection of additional specimens of these species allowed a re-evaluation of morphological and/or morphometric variations. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Applied Technology for Agricultural Science / Revista Brasileira de Tecnologia Aplicada nas Ciências Agrárias is the property of Brazilian Journal of Applied Technology for Agricultural Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Anthurium augustinum (Araceae) complex (including A. augustinum K. Koch & Lauche, A. hatschbachii E. G. Gonç., A. jureianum Cath. & Olaio, A. laucheanum K. Koch, A. lhotzkyanum Schott, A. lucidum Kunth, A. maximiliani Schott and A. parvum N.E.Br.) is endemic to the Brazilian Atlantic Forest. Some of these taxa are strictly endemic, with only the type population known, and may occur in sympatry. These species share a leaf morphology in which the blade is deflexed at the petiole insertion and is usually cordate, or rarely rounded at the base due to congenital fusion of the basal lobes. Taxonomic delimitation of the species in this group is difficult because of overlap in diagnostic characters such as deflexed leaf blade, cordate, rounded or semi-oval leaf base and camptodromous venation. The objective of the study was to test whether these taxa could be recognized using leaf morphometrics. Elliptic Fourier analysis was carried out on a sample of 257 individuals in 12 natural populations. The results of multivariate analyses indicated that in various comparisons, leaf shape was not diagnostic due overlap of variation within and between populations of different species. Consequently, we propose that A. laucheanum, A. lhotzkyanum and A. maximiliani should be regarded as synonyms of A. augustinum, and that the following five species be recognized in this complex: A. augustinum, A. hatschbachii, A. jureianum, A. lucidum and A. parvum. We also formally designate two neotypes ( A. laucheanum, A. maximiliani), one lectotype ( A. augustinum) and one epitype ( A. augustinum). (© 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Approximately 70% of the angiosperm species are polyploid, an important phenomenon in the evolution of those plants. But ploidy estimates have often been hindered because of the small size and large number of chromosomes in many tropical groups. Since polyploidy affects cell size, morphometric analyses of pollen grains and stomata have been used to infer ploidy level. Polyploidy is present in many species of the Cerrado, the Neotropical savanna region in Central Brazil, and has been linked to apomixis in some taxa. Eriotheca gracilipes and Eriotheca pubescens are common tree species in this region, and present cytotypes that form reproductive mosaics. Hexaploid individuals (2n = 6x = 276) are polyembryonic and apomictic, while tetraploid and diploid individuals (2n = 2x = 92, 2n = 4x = 184) are sexual and monoembryonic. We tested whether morphometric analysis can be used to estimate ploidy levels in E. gracilipes and E. pubescens individuals. Pollen material from diploid and hexaploid individuals of E. gracilipes, and tetraploid and hexaploid individuals of E. pubescens, were fixed in 50% FAA, and expanded leaves were dried in silica gel. Pollen grains and stomata of at least five individuals from each population were measured. The results demonstrate that all measures were significantly different among cytotypes. Individuals with higher levels of ploidy (hexaploid) all presented measurements that were higher than those with lower levels (diploid and tetraploid). There was no overlap between ploidy levels in each species at 95% confidence interval. Thus, the size of the pollen grains and stomata are effective parameters for analysis of ploidy levels in E. gracilipes and E. pubescens. [ABSTRACT FROM AUTHOR]

Leaf characters of populations of the aquatic macrophyte Montrichardia linifera were studied using geometric morphometrics to compare variation with traditional circumscriptions of the two recognized species. Two hundred and ten individuals were sampled from seven populations in the delta region of the Rio Parnaíba, north-east Brazil. Six landmarks of the leaf blade were digitized from images and analysed with MorphoJ software. Procrustes-aligned configurations were studied using principal component analysis and canonical variates analysis in the pooled data and individual populations. Sinus shape variation was studied using landmark configurations of the posterior lobe basiscopic lamina. Covariation of leaf blade shape, basiscopic lamina shape, secondary vein number and petiole ligule length was investigated with partial least squares analysis. Allometry of these variables with leaf blade centroid size was investigated using multivariate regression, linear modelling and analysis of covariance. Measured variables varied continuously over the ranges previously reported for the two species. The characters of the two species morphotypes covaried and were only partly influenced by allometric effects. Symmetric shape variables predominated, but a distinctive left- and right-handed asymmetry occurred in all populations. Genetic and ecological studies are needed to investigate the significant inter-population differences further. The study offers a methodology for a broader combined morphometric/molecular investigation. © 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 170, 554-572. [ABSTRACT FROM AUTHOR]

Predatory mites identified as Neoseiulus paspalivorus DeLeon (Phytoseiidae) have been considered as agents for classical biological control of the coconut mite, Aceria guerreronis Keifer (Eriophyidae), in Africa and elsewhere. Preliminary identification of geographically distinct populations as belonging to the same species ( N. paspalivorus) was based on their morphological similarity. However, laboratory studies recently conducted have shown large differences in feeding behaviors and biological characteristics among individuals collected from three geographic origins: Brazil (South America), Benin and Ghana (West Africa). As morphologically similar specimens do not necessarily belong to the same species, we evaluated under laboratory conditions, reproductive compatibility between the specimens from three geographic locations to ascertain their conspecificity. Morphological measurements were also made to determine whether there is a means of discriminating between them. Inter-population crosses showed complete reproductive isolation between the three geographic populations, but interpopulation discontinuities in morphometric characters were absent. These results indicate that the tested specimens are distinct biological entities despite morphological similarity. Further molecular genetic studies are therefore proposed, including screening for endosymbionts and assessment of genetic differentiation, to determine the cause of reproductive incompatibility and to clarify the taxonomic relationship between those populations. [ABSTRACT FROM AUTHOR]

Geomorphological maps can be documents of restricted use due to the complexity of their content. The research project now presented proposes the geomorphological mapping of the area covered by six official topographic sheets at a scale of 1:50,000, located in the northeastern part of Santa Catarina State, southern Brazil. The mapping of the first sheet, Garuva, was based on the graphic representation of the relief structure, it's units and sub-units as polygons. Processes and landforms/types were represented as line and point symbols. The geologic and morphometric (slope) information were represented in individual smaller maps placed beside the main legend. The mapping was accomplished from a Landsat satellite image and aerial photographs at 1:60,000 scale. The relief structure is represented in three main color groups: gray for the plateau, violet for the escarpments and yellow/orange/brown for the plains. The proposed mapping presents geomorphological information in a simple and didactic way, in order to allow its use also by professionals not necessarily related to geosciences. [ABSTRACT FROM AUTHOR]

A population of the little-known species Aorolaimus banoae was collected in the municipality of Cananéia, São Paulo state, Brazil, in a remnant of the once far more extensive Brazilian Atlantic Forest. As the original description of this species was based on only three females and nine males, additional morphometric and morphological data, including SEM studies, are presented. It is suggested that A. banoae is a member of the original fauna associated with the coastal Atlantic forest. [ABSTRACT FROM AUTHOR]

The species Proceratophrys cristiceps belongs to the genus Proceratophrys within the family Cycloramphidae. These amphibians are found exclusively in South America in the morphoclimatic domain of the semi-arid depression zones in northeastern Brazil known as the Caatinga. We examined intrapopulational variation using univariate and multivariate statistics with traditional and geometric morphometrics, which supported the existence of two morphotypes of this species. Our results indicated significant degrees of variation in skeletal characteristics between some natural populations of this species. Careful analyses of variability levels are fundamental to avoid taxonomic errors, principally in populations that demonstrate characteristics intimately associated with their area of occurrence, as is the case of Proceratophrys cristiceps. [ABSTRACT FROM AUTHOR]

We carried out a demographic study and evaluated the genetic and morphological variability in five populations of the endangered Sophronitis sincorana (Orchidaceae) endemic to Northeastern Brazil, based on allozyme and morphometric analyses. Plant density was approximately 0.5 plants/m2, and the projected total number of plants was approximately 50,000 individuals. However, fruit set and recruitment of individuals are rare. The genetic variability was very high in all populations ( P = 100, A = 3.0−3.5, H e = 0.33−0.48), and all populations presented similar values of morphological variability. Low genetic and morphological structuring were found in the species ( F ST = 0.053, AMRPP = 0.018). The elevated coefficient of endogamy encountered in populations of S. sincorana indicates the occurrence of structuring within the populations. The lack of correlation between morphological and genetic variation in this species indicates that none of the markers examined should be used separately for either conservation purposes. [ABSTRACT FROM AUTHOR]

Allozymic and morphometric studies were carried out on ten populations of Syngonanthus mucugensis (Eriocaulaceae), a species from north-eastern Brazil threatened by extinction. Genetic and morphological variability was low or moderately low in all populations, being lower in populations from Rio de Contas/Catolés ( PL = 14.3–21.4, A = 1.1–1.2, He = 0.026–0.059, D2M = 26.893–33.157) than in those from Mucugê ( PL = 28.6–35.7, A = 1.3–1.5, He = 0.078–0.164, D2M = 28.999–45.077). A high coefficient of endogamy ( Fis = 0.257) was found, which can be explained by the reproductive characteristics and distribution of the species. The values for genetic and morphological structuring ( Fst = 0.512 and AMRPP = 0.175, respectively) were high as a result of the differentiation between populations from the two areas. The mean genetic identity between populations from the two areas (0.812) was much lower than between populations from the same area (Mucugê, 0.980; Rio de Contas/Catolés, 0.997). These results indicate that we are dealing with two distinct taxa and, as a result of the nature of the morphological differences found, a new subspecies is described for the populations of the region of Rio de Contas and Catolés, Syngonanthus mucugensis ssp. riocontensis. Such conclusions raise important implications for the conservation of Syngonanthus mucugensis, and will be used in the drawing up of management plans for its conservation. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153, 401–416. [ABSTRACT FROM AUTHOR]

In a survey of entomopathogenic nematodes in Brazil, a nematode isolate of the genus Heterorhabditis was found. The nematode was collected from soil by the insect-baiting technique and maintained in the laboratory on last instar Galleria mellonella (L.) larvae. Morphological and molecular studies of the isolate showed that the nematode is a new species. Light and scanning electron microscopy, DNA characterisation and phylogeny were used for this description. Heterorhabditis amazonensis n. sp. is morphologically similar to H. baujardi, H. floridensis, H. mexicana and H. indica, and can be distinguished from these species mainly by male and female characters. Fifty percent of Heterorhabditis amazonensis n. sp. males have two pairs of bursal papillae in the terminal group; 25% with two papillae on one side and one papilla on the other side and 25% with one pair of papillae. Twenty percent of the population has a curved gubernaculum. The percentage of the gubernaculum to spicule length (GS%) is lower than that of H. mexicana (50 vs 56), and the length of the spicule relative to anal body diam. (SW%) is lower than that of H. mexicana (152 vs 167) and H. baujardi (152 vs 182). The female can be differentiated from related species by its unique vulva pattern. In a phylogenetic tree, the new species, H. floridensis, H. baujardi and H. mexicana form a monophyletic group, a sister group to H. indica. The new species has evolved three autapomorphic nucleotide character states, differing from its sister taxa H. mexicana at 22, and H. baujardi at 15, aligned positions. [ABSTRACT FROM AUTHOR]

Characterization, management and protection of biodiversity are the most prominent challenges in conservation biology. Analyses on molecular similarity (Random Amplified Polymorphic DNA-Polymerase Chain Reaction, RAPD-PCR) and morphologic patterns (morphometric and meristic characters) were performed to evaluate the existence of population structuring in the Doce river basin, in a widespread small-sized characin, Astyanax bimaculatus. Three hundred (300) individuals were collected from six locations isolated by waterfalls or dams, in the Doce river basin, Minas Gerais State, Brazil. Genetic differentiation among tributaries was significant ( p<0.00001) and accounted for 21% of total variance ( p<0.00001). Only the Grande waterfall of the Casca river was an effective factor for differentiation of populations ( p<0.00001), and meristic characters were also consistent with molecular data. We concluded that genetic and morphologic variation of this species was not necessarily associated with waterfalls and that molecular and meristic data are effective predictors of population divergence in this basin. The consequences of these findings for the protection and management of aquatic biodiversity were discussed. [ABSTRACT FROM AUTHOR]

• Background and Aims Melocacatus paucispinus (Cactaceae) is endemic to the state of Bahia, Brazil, and due to its rarity and desirability to collectors it has been considered threatened with extinction. This species is usually sympatric and inter-fertile with M. concinnus, and morphological evidence for hybridization between them is present in some populations. Levels of genetic and morphological variation and sub-structuring in populations of these species were assessed and an attempt was made to verify the occurrence of natural hybridization between them.• Methods Genetic variability was surveyed using allozymes (12 loci) and morphological variability using multivariate morphometric analyses (17 vegetative characters) in ten populations of M. paucispinus and three of M. concinnus occurring in the Chapada Diamantina, Bahia.• Key Results Genetic variability was low in both species (P = 0·0–33·3, A = 1·0–1·6, He = 0·000–0·123 in M. paucispinus; P = 0·0–25·0, A = 1·0–1·4, He = 0·000–0·104 in M. concinnus). Deficit of heterozygotes within the populations was detected in both species, with high values of FIS (0·732 and 0·901 in M. paucispinus and M. concinnus, respectively). Evidence of hybridization was detected by the relative allele frequency in the two diaphorase loci. High levels of genetic (FST = 0·504 in M. paucispinus and 0·349 in M. concinnus) and morphological (A = 0·20 in M. paucispinus and 0·17 in M. concinnus) structuring among populations were found.• Conclusions The Melocactus spp. displayed levels of genetic variability lower than the values reported for other cactus species. The evidence indicates the occurrence of introgression in both species at two sites. The high FST values cannot be explained by geographical substructuring, but are consistent with hybridization. Conversely, morphological differentiation in M. paucispinus, but not in M. concinnus, is probably due to isolation by distance. [ABSTRACT FROM AUTHOR]

Species limits in the genus Oxymycterus have been controversial because of difficulties in detecting discrete morphological and cytogenetic variation. Several authors have considered many of the species described from Brazil to be conspecific with O. rufus, including O. dasytrichus described from Bahia. This tendency represents a null hypothesis for the species-level diversity within the genus. A recently proposed alternative hypothesis based on analyses of allopatric samples recognizes O. rufus and O. dasytrichus as valid species within rufus and dasytrichus species complexes, respectively. Two sympatric forms of Oxymycterus from Viçosa, Minas Gerais State, southeastern Brazil, are phenotypically similar to members of these 2 species-groups. Investigation on the status of these populations and their relationships to the rufus and dasytrichus complexes provided a test of the alternative hypothesis regarding diversity within the genus. Morphometric, morphological, and molecular (cytochrome-b DNA sequences) comparisons of samples representing the rufus, dasytrichus, and judex species-groups provided evidence that the 2 sympatric forms from Viçosa are distinct evolutionary units, one related to the dasytrichus species-group and the other to the rufus species-group. The structures of morphological and molecular variation within each species-group supported an isolation-by-distance model of phenotypic differentiation in the rufus group, and a smooth pattern of phenotypic differentiation along a north-south axis in the dasytrichus group. The relevance of these patterns for species delimitation within these groups and the validity of O. dasytrichus and O. rufus are discussed. [ABSTRACT FROM AUTHOR]

Morphometric analyses of vegetative and floral characters were conducted in 21 populations of five Pleurothallis (Orchidaceae) species occurring in Brazilian ‘campo rupestre’ vegetation. A phylogenetic analysis of this species group was also carried out using nuclear ribosomal DNA internal transcribed spacers (ITS1 and ITS2). Results of the ordination and cluster analyses agree with species’ delimitation revealed by taxonomic and allozyme studies. The groups formed in ordination analysis correspond to the pollinator groups determined in a previous pollination study. Relationships among the species in the cluster analysis using only vegetative characters are similar to those found in a previous allozyme study, but those indicated by cluster analysis using only floral characters differ. These results support the hypothesis that floral similarities are due to convergence driven by similar pollination mechanisms, and therefore floral traits may not be good indicators of phylogenetic relationships in this group. The results of the phylogenetic analysis support this conclusion to some extent. There is no correlation between genetic (allozyme) and morphological variability in the populations nor in the way this variability is distributed among conspecific populations. We describe a new subspecies of Pleurothallis ochreata based on differences in vegetative and chemical characters as well as geographic distribution. Absence of differentiation in floral characters, attraction of the same pollinator species, interfertility and genetic similarity support the argument for subspecific rather than specific status. [ABSTRACT FROM PUBLISHER]

A juvenile male megamouth shark was caught by a commercial longline vessel off Brazil. This specimen is the only juvenile megamouth examined and the only one from the Atlantic Ocean. Megamouth shark is one of the rarest sharks in the world. Only 14 specimens have been reported since its description in 1983 by Taylor et al. All previous specimens examined have been adults from the Pacific and Indian Oceans. It appears that the species is cosmopolitan. [ABSTRACT FROM AUTHOR]