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Fabrizio Stefani F. Benzoni S.-Y. Yang M. Pichon P. Galli C. A. Chen 《Coral reefs (Online)》2011,30(4):1033-1049
A combined morphological and genetic study of the coral genus Stylophora investigated species boundaries in the Gulf of Aden, Yemen. Two mitochondrial regions, including the hypervariable IGS9 spacer
and the control region, and a fragment of rDNA were used for phylogenetic analysis. Results were compared by multivariate
analysis on the basis of branch morphology and corallite morphometry. Two species were clearly discriminated by both approaches.
The first species was characterised by small corallites and a low morphological variability and was ascribed to a new geographical
record of Stylophora madagascarensis on the basis of its phylogenetic distinction and its morphological similarity to the type material. The second species was
characterised by larger corallite size and greater morphological variability and was ascribed to Stylophora pistillata. The analysis was extended to the intrageneric level for other S.
pistillata populations from the Red Sea and the Pacific Ocean. Strong internal divergence was evident in the genus Stylophora. S. pistillata populations were split into two highly divergent Red Sea/Gulf of Aden and western Pacific lineages with significant morphological
overlap, which suggests they represent two distinct cryptic species. The combined use of morphological and molecular approaches,
so far proved to be a powerful tool for the re-delineation of species boundaries in corals, provided novel evidence of cryptic
divergence in this group of marine metazoans. 相似文献
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We analyzed the morphology and habitat use of 16 small-sized fish species that are abundant in the Rio das Velhas basin using
17 morphological attributes. Habitat use was characterized in terms of the species mean density considering three hydraulic
factors: substrate, water depth and mean water velocity. The distribution of species within the morphological space demonstrated
congruence between the morphological attributes of a species, and their occupation of vertical microhabitats. Based on this
data, the species could be classified as benthic A, benthic B or nektonic zone-dwelling species. Benthic A and B species differed
mainly in relation to their body shapes, which were fusiform or depressed, respectively. Generally, habitat selection by each
species was related to certain hydraulic factors, water velocity in particular. Siluriformes generally had morphological or
behavioral adaptations to live in fast flowing habitats, and they were found more frequently than Characiformes in microhabitats
with greater water velocities. Benthic species were the most selective with respect to substrate type. Between congener species,
the habitat use of Serrapinnus heterodon and Serrapinnus piaba greatly overlapped, but these species were separated in morphological space. In contrast, Characidium species were closely related in morphological space but had great habitat segregation. Fish requirements and habitat use
are poorly understood but are important to species management and habitat restoration. 相似文献
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Manuela Sim-Sim Olga M. Afonina Tereza Almeida Aurélie Désamoré Benjamin Laenen César Augusto Garcia 《分类学与生物多样性》2013,11(5):451-463
An integrative taxonomic approach, including molecular phylogenetic reconstructions based on plastid rps4-trnF and nuclear ITS sequences, statistical analysis of morphological-anatomical characters, and classical taxonomy, indicates that the reduction of 13 Amphidium species to three in a recent morphological revision represents a case of too extensive lumping. Instead, six Amphidium species can be distinguished based on molecular and morphological data, the widespread Amphidium lapponicum, A. mougeotii, and A. tortuosum, as well as the Macaronesian endemic A. curvipes, the North American endemic A. californicum, and a newly discovered species from Central Asia (southern Siberia and northern Mongolia), A. asiaticum sp. nov. Diagnostic morphological characters for all six species are discussed. The present data confirm that species diversity of Amphidium is highest in the Holarctic, where all six species occur. 相似文献
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Andrey V. Chkalov 《Nordic Journal of Botany》2015,33(5):518-521
A morphological study of specimens collected by the author and a critical revision of the key herbarium collections revealed a new rather peculiar taxon of Alchemilla occurring in almost every region of the Middle Volga basin, Russia. This novelity is here described as A. schmakovii and images of the principal morphological features of this species are provided. The new species is compared with related species in A. sect. Alchemilla (e.g. A. micans) and sect. Plicatae (e.g. A. breviloba) based on morphological characteristics. 相似文献
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Artemisia is an important genus of Asteraceae and has a high number of taxa, ecological and economic importance. Its natural classification
has not been achieved and the taxonomists are trying to solve the problem of its classification over the last two decades.
The genus Artemisia can be divided into five large sections namely: Absinthium DC, Artemisia L., Dracunculus Besser, Seriphidium Besser and Tridentatae (Rybd.). In the present study, three species (A. vulgaris, A. roxburghiana and A. absinthium) belonging to groups Artemisia (A. vulgaris and A. roxburghiana) and Absinthium (A. absinthium) were collected from Rawalakot, Azad Jammu and Kashmir. The species were analyzed for the assessment of morphological and
genetic diversity and relationship was estimated among and within the different species of Artemisia. The morphological and molecular data were analyzed using software NTSYS (Numerical Taxonomy and Multivariate Analysis System)
pc version 2.01. For molecular study, random amplification of polymorphic DNA (RAPD) was used to detect genetic variations
among the species. Out of the ten random primers used, nine have given amplification profiles. A total 611 bands were produced
by all the primers, of which 419 were polymorphic and level of polymorphism was detected to be 68% across all the samples
of studied species. Based on the results obtained, it has been observed that there is a wide range of diversity both at morphological
and molecular level among and within the species. Further, mixed pattern of grouping in cluster analysis was found, indicating
the close affinities of species with each other. 相似文献
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K. Wolff 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1991,81(1):119-126
Summary The level of electrophoretic variability in three Plantago species, P. major, P. coronopus, and P. lanceolata, was analyzed in relation to their breeding systems and compared with their morphological variability. From each species several populations were analyzed. The outcrossing P. lanceolata had the highest level of electrophoretic variability and the lowest population differentiation. The inbreeding P. major showed the opposite: a low level of electrophoretic variability and a high population differentiation. P. coronopus, with an intermediate breeding system, had an intermediate level of variability and differentiation. In comparing the species, it appeared that P. coronopus and P. major showed good concordance in the distribution of both kinds of variability, each having only a slightly higher morphological than electrophoretic differentiation between populations. P. lanceolata showed a higher morphological than electrophoretic differentiation between populations. A comparison of populations, within species, revealed good concordance of electrophoretic and morphological variability only within P. coronopus, while some populations of the other two species had relatively lower morphological variability compared with electrophoretic variability.Grassland Species Research Group Publication No. 182 相似文献
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An investigation of eleven populations of Sabatia, utilizing twelve morphological traits and fifteen allozymic loci, revealed the presence of three species in the section Campestria. Currently, the section has two recognized species, S. campestris Nutt. and S. arenicola Greenm. A stepwise discriminant analysis of the morphological data indicated the presence of the third previously described species, S. formosa Buckl. Eight of the loci were either monomorphic or there were no allozyme frequency differences among the three species. An analysis of the allozyme frequencies of the seven polymorphic loci substantiated the presence of S. formosa. Ecological and phenological phenomena further separate the three species. A distribution map of the populations analyzed, populations observed, and populations represented in herbarium specimens indicates that the ranges of the three species are separate although sympatry does occur. Thus, the morphological form described and designated S. formosa by Buckley in 1862 is a separate species. 相似文献