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1.
We describe the tadpole of Scinax aromothyella from the surroundings of Quebrada de los Cuervos, Departamento de Treinta y Tres, Uruguay. It shares with other larvae of the Scinax catharinae clade the slightly depressed body, a dextral vent tube that reaches the free margin of the ventral fin, and the oral disc with a dorsal gap in the marginal row of papillae and with a concave posterior edge. It is most similar to the tadpole of Scinax berthae, from which it differs in the larger total length of S. aromothyella.

Describimos la larva de Scinax aromothyella de los alrededores de la Quebrada de los Cuervos, Departamento de Treinta y Tres, Uruguay. Comparte con las larvas de otras especies del clado de Scinax catharinae el tener el cuerpo levemente deprimido, el tubo proctodeal dextro que alcanza el borde libre de la aleta ventral, y el disco oral con un claro rostral en la hilera de papilas marginales y con su borde posterior cóncavo. Es muy parecida a la larva de Scinax berthae, de la que difiere en la mayor longitud total de S. aromothyella.  相似文献   

2.
Scinax species are still underrepresented in cytogenetic studies, mainly with respect to populations from northeastern and northern Brazil. In this study, we provide new chromosomal information on Scinax boesemani, S. camposseabrai, S. garbei, S. pachycrus, S. trilineatus and S. x-signatus, all belonging to clade S. ruber. They were collected at two locations in the Caatinga biome (northeastern Brazil) and at one in the Amazon (northern Brazil) biomes. Chromosomes were analyzed by conventional staining, C-banding, Ag-NOR staining, and fluorochrome staining. All species shared a modal diploid value of 2n = 24 and fundamental arm number (FN) of 48. Moreover, both chromosomal size and morphology were similar to other species in this Scinaxclade. C-banding revealed centromeric heterochromatin in all species, along with terminal species-specific C-bands in some species. Active nucleolar organizer regions (Ag-NORs) were identified at 11q in most species, except for S. boesemani and S. garbei (Ag-NORs at interstitial region of 8q). Differing from most anurans, GC-rich regions were not restricted to NORs, but also coincident with some centromeric and terminal C-bands. These data contribute to the cytotaxonomy of Scinax by providing chromosomal markers and demonstrating the occurrence of microstructural rearrangements and inversions on chromosomal evolution of Scinax.  相似文献   

3.
Agriculture and pasture activities are the main drivers for habitat reduction, directly affecting amphibian assemblages. In the Cerrado, the progress of agricultural and pasture areas negatively affects aquatic environments and their organisms, once the suppression of marginal vegetation reduces the natural protection against allochtone stressors. One possible way to measure the stress level is the Fluctuating Asymmetry (FA), which is calculated based on the deviations in the development of bilateral morphological traits of the organism. Herein, we evaluated whether environments with a higher degree of agropastoral influence and reduced marginal vegetation can increase FA levels in tadpoles of two common and widely distributed anuran species in the Cerrado (Physalaemus cuvieri and Scinax fuscomarginatus). We sampled and classified water bodies according to the percentage of agropastoral land use and marginal vegetation, and measured four morphological traits of tadpoles to evaluate the degree of FA. We found that in environments with intensive agropastoral land use, tadpoles of P. cuvieri and S. fuscomarginatus had higher FA in nostril‐snout distance (NSD). In environments with reduced marginal vegetation, tadpoles of S. fuscomarginatus had higher FA in eye width (EW), but no effect was detected for tadpoles of P. cuvieri. These morphological traits (i.e. nostrils and eyes) are associated to individual fitness of tadpoles. Thus, these developmental deviations can affect species fitness and population homeostasis over time, contributing to generate stochastic population dynamics and increasing the vulnerability of native species to local extinctions. The use of FA as a tool to measure environmental impact on species with potential to be used as bioindicators can contribute to generate and test hypothesis when integrated with long‐term studies.  相似文献   

4.
Acoustic signals are employed to support the correct designation of species and enables the discrimination between individuals. We analyzed both intra and interindividual variability of the advertisement call of Physalaemus centralis on the basis of specimens recorded in eight localities of the Cerrado in central Brazil. Within-individual variation, most of the call parameters were static properties. Both spectral and temporal call properties were dynamic between individuals. All call proprieties varied more between individuals than within an individual. Our study adds important data for future studies on the taxonomy and phylogeny of the P. cuvieri clade.  相似文献   

5.
The hylid frog genus Scinax ranges from southern Mexico to eastern Argentina. The 84 recognized species are currently arranged in five groups: the Scinax rubra , Scinax rostrata , Scinax catharinae , Scinax staufferi , and Scinax perpusilla species groups. Although a few species groups are distinctive, compelling evidence of monophyly is lacking for three groups, and their interrelationships remain virtually unknown. With the objective of testing the monophyly of the species groups and exploring their interrelationships, a cladistic analysis was performed, employing 86 characters from osteology, myology, adult and larval external morphology, reproductive biology, and karyotypes taken from 36 representative species of the five species groups plus eight outgroup taxa. The analysis of the resulting data matrix shows moderately well-supported (as assessed through Bremer support and parsimony jackknifing) S. catharinae and S. rostrata species groups. The S. staufferi species group is polyphyletic, as currently composed, given that some of its species are nested within the S. catharinae species group. The only representative of the S. perpusilla species group is the sister species of the S. catharinae species group. Although weakly supported, the representatives of the S. rostrata and S. staufferi species groups are nested, separately, within the S. rubra species group. In order to have a taxonomy consistent with these results, it is proposed not to recognize the S. rubra group but to recognize a more inclusive rubra clade that includes all studied exemplars of the former S. rubra group, plus some of the S. staufferi group and all of the S. rostrata group. Similarly, a catharinae clade is recognized, within which all studied exemplars of the S. catharina e group (that now includes Scinax berthae and Scinax agilis ) and the one studied representative of the S. perpusilla group are included.  相似文献   

6.
Herein, we provide external and internal morphological data of Scinax skuki tadpoles from its type locality. The benthic tadpole of S. skuki has eyes and nostrils positioned dorsally, vent tube dextral and reaching the free margin of the ventral fin, oral disk ventral with posterior margin concave when partially closed, labial tooth row formula 2/3, and the presence of nonpigmented spurs behind the lower jaw. These characters, together with the absence of a tectum parietale, and the shapes of the pars articularis quadrati and suprarostral, are useful for species identification and may be informative for systematic purposes.  相似文献   

7.
The taxonomy of the endemic arboreal snail Satsuma albida species complex from Taiwan was unclear due to the animals' highly similar morphology, and their nocturnal and strict arboreal behaviour, leading to difficulties in collecting living specimens. This article is the first comprehensive comparative study on the systematics and taxonomy of this species complex using external morphology, anatomy of the reproductive system and molecular phylogeny. Consequently, two subspecies of S. albida are raised to species status, namely S. insignis and S. mollicula. Fourteen new species are also described. Fourteen of the 17 species showed polymorphism in banding pattern amongst populations and other species retained the whitish unity as seen in S. albida. Distributions of almost all taxa are geographically limited, with the exception of S. polymorpha sp. nov . The phylogeny of these species was reconstructed using 20 morphological characters and molecular data from the partial sequences of mtDNA CO1 and 16S rRNA genes, and the complete ITS2 sequence. The molecular phylogeny revealed three subclades (west, east and polymorpha clade) and revealed that these snails are monophyletic, originating from a ground‐dwelling ancestor. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 154 , 437–493.  相似文献   

8.
Scinax (Anura: Hylidae) is a species-rich genus of amphibians (113 spp.), divided into five species groups by morphological features. Cladistic analyses however revealed only two monophyletic clades in these groups: Scinax catharinae and Scinax ruber. Most species from the S. catharinae clade are found in Atlantic rainforest, except for Scinax canastrensis,S. centralis, S. luizotavioi, S. machadoi,S. pombali and S. skaios. In the present work, specimens of Scinax collected in Chapada dos Guimarães, central Brazil, were morphologically compatible with species from theS. catharinae group. On the other hand, genetic analysis based on mitochondrial (16S and 12S) and nuclear (rhodopsin) sequences revealed a nucleotide divergence of 6 to 20% between Scinax sp. and other congeners from the Brazilian savannah (Cerrado). Accordingly, Bayesian inference placed Scinax sp. in the S. catharinae clade with high support values. Hence, these findings strongly indicate the presence of a new species in the S. catharinae clade from the southwestern portion of the Brazilian savannah. To be properly validated as a novel species, detailed comparative morphological and bioacustic studies with other taxa from Brazil such asS. canastrensis, S. centralis, S. luizotavioi, S. machadoi, S. pombali and S. skaios are required.  相似文献   

9.
Maximum likelihood and Bayesian analyses of nrDNA (ETS1f) and plastid DNA (rpl32‐trnL, trnH‐psbA) sequence data are presented for ‘C3Cyperus’ (Cyperaceae). The term ‘C3Cyperus’ indicates all species of Cyperus s.l. that use C3 photosynthesis linked with eucyperoid vegetative anatomy. Sampling comprises 77 specimens of 61 different taxa, representing nearly all previously recognized subdivisions of C3Cyperus and the segregate genera Courtoisina, Kyllingiella and Oxycaryum. According to our results, the Cyperus clade is divided in six well‐supported clades. The first of these clades (clade 1) forms three subclades largely corresponding to Cyperus sections Haspani, Incurvi and Diffusi. Clade 2 comprises the entirely New World C. section Luzuloidei sensu Denton (1978). Clade 3 is a highly diverse clade including two subclades: clade 3a, C. sections Pseudanosporum and Anosporum plus the segregate genera Courtoisina and Oxycaryum; and clade 3b, C. section Fusci. Clade 4 corresponds to C. section Alternifolii and clade 5 to C. section Leucocephali plus the segregate genus Kyllingiella. The sixth clade is a well‐supported monophyletic clade encompassing all C4Cyperus s.l. species (‘C4Cyperus’). This study establishes a phylogenetic framework for future studies. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 167 , 19–46.  相似文献   

10.
The freshwater isopod Paramphisopus palustris is ubiquitous and abundant in the groundwater-fed wetlands of the Swan Coastal Plain around Perth, Western Australia. Taxonomically, an additional variety (P. palustris fairbridgei) and species (P. montanus) are recognized from geographically outlying localities. Here a 486 bp fragment of cytochrome c oxidase subunit I (COI) mtDNA was sequenced in 68 individuals from 23 localities in order to evaluate the accepted taxonomy, to examine the evolutionary history of the species, and to identify lineages to prioritize conservation of wetlands already substantially modified. MtDNA showed individual populations to be largely distinct and differentiated. The 41 unique haplotypes formed seven independent, geographically defined networks. Phylogenetic analysis retrieved corresponding subclades, with three well-supported larger clades occurring (1) north of the Swan River, (2) south of the Swan River, and (3) in an area further south. A clear pattern of isolation by distance was detected suggesting an ancient serial founder event, with the pattern possibly persisting in the face of limited gene flow through priority effects. The possibility of incipient speciation, the monophyly of the recognized subspecies and the paraphyly of P. palustris with respect to P. montanus, suggest that the current taxonomy is invalid and requires re-examination. Divergences suggest a mid- to early Pliocene divergence of the major clades, with early Pliocene divergences among subclades probably driven by documented intense arid periods. Lineages are present in wetlands in geologically younger environments suggesting in situ survival and persistence. Seven Evolutionarily Significant Units were identified for the conservation of Paramphisopus, two of which are not currently represented in conservation reserves. With increased water demand and the negative impact of surrounding land-use, the current study provides a first phylogeographic assessment of conservation priorities for wetlands of the Swan Coastal Plain. Electronic supplementary material The online version of this article (doi: ) contains supplementary material which is available to authorized users. Handling editor: C. Sturmbauer  相似文献   

11.
Species level taxonomy and phylogeographical distribution patterns in the freshwater rhodophyte Sirodotia are resolved through phylogenetic inferences based on rbcL and cox2–3 sequence data. Previous studies focused on the taxonomy of specific Sirodotia species or the distributions across a limited geographical region. Our molecular phylogenies included samples attributable to five recognized Sirodotia species and include collections from Australia, Brazil, Costa Rica, Canada, Finland, Mexico, New Zealand, South Africa and the United States. Both rbcL and cox2–3 phylogenies inferred S. suecica, S. tenuissima and S. goebelii as a monophyletic group with little sequence divergence. This result supports the synonymy of S. tenuissima and S. goebelii with S. suecica (the species name with priority). Within this clade, samples collected from Australia and New Zealand formed a monophyletic group with no other discernible phylogeographical patterns within S. suecica. This result seems to be somewhat unusual in the Batrachospermales, as other species have shown greater genetic variation among geographically distant locations. As in previous studies, S. huillensis and S. delicatula were inferred as a separate species based on the rbcL phylogeny, supporting the current taxonomy. A specimen of S. aff. huillensis from South Africa, may represent a new species but further research is necessary before it can be designated as such.  相似文献   

12.
Polystichum is one of the largest and most taxonomically complex fern genera in China. The evolutionary relationships of Chinese Polystichum and related genera, and the relationship between our Polystichum phylogeny and ecogeographic distribution, were tested by the use of DNA sequence data. Fifty-one species of Polystichum and 21 species in allied genera were sequenced for the plastid intergenic spacers rps4-trnS and trnL-F. Maximum parsimony and Bayesian phylogenetic analyses of both individual and combined data sets showed that Chinese Polystichum as commonly recognized was paraphyletic: one clade (the CCPC clade) included Cyrtomidictyum lepidocaulon, two Cyrtogonellum species, three Cyrtomium species, and a small number of Polystichum species usually occurring on limestone. A second clade, Polystichum sensu stricto, included the remainder of the Polystichum species; these often occur on non-limestone substrates. The remaining Cyrtomium species formed the third clade. Three subclades resolved within Polystichum sensu stricto (s.s.) clade do not correspond with recent sectional classifications, and we outline the issues relevant to a new classification for the genus. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

13.
Small subunit (SSU) and large subunit (LSU) rDNA sequences have been commonly used to delineate the taxonomy and biogeography of the planktonic diatom genus Skeletonema, but the genes occur as multiple copies and are therefore not suitable for barcoding purposes. Here, we analyzed phylogenetic relationships of Skeletonema using the mitochondrial‐encoded cytochrome c oxidase I gene (cox1), as well as partial LSU rDNA (D1–D3) and SSU rDNA, to identify the factors that define species and to evaluate the utility of these three markers for this taxon. Twelve Skeletonema species were divided into six clades, I–VI, each of which comprised the same species by the three markers: clades I (S. japonicum, S. grethae, S. pseudocostatum, and S. tropicum), II (S. menzelii), III (S. dohrnii and S. marinoi), IV (S. costatum, S. potamos, and S. subsalsum), V (S. grevillei), and VI (S. ardens). However, the branching order among these clades was incongruent among the markers. In clade III, six S. marinoi strains had identical cox1 sequences. These S. marinoi strains branched along with S. dohrnii, except for strains from the Gulf of Naples, with high support in cox1. Species delimitation between S. dohrnii and S. marinoi was therefore not supported. In clade IV, S. costatum and S. subsalsum were robustly clustered, with S. potamos as a sister clade in the cox1 tree, not in the LSU and SSU trees. In clade II, cox1 also confirmed that S. menzelii includes three subclades potentially distinguishable from each other by morphological features. Cox1 proved to be the most useful marker for the identification of Skeletonema species because it gave a tree with highly supported clades, has sufficient variation within and among species, encodes a protein in a single copy, and requires relatively few primers.  相似文献   

14.
Phymaturus comprises 44 species mainly distributed along the south‐west of South America on both sides of the Andes. In this study we present a phylogenetic analysis of Phymaturus of the palluma group, one of its two large clades, including almost all described species. This analysis duplicates the number of in‐group taxa compared with previous contributions. We performed a total‐evidence analysis, combining molecular and morphological characters: sequencing fragments of cytochome b (cytb), 12S, and ND4, for all terminals; describing 45 new morphological characters; and incorporating all DNA sequences available from GenBank. Separate analyses of morphology and DNA partitions are presented and discussed in detail. Seven subclades are recognized here. We named three new subclades and redefined another, found to be paraphyletic. In order to recognize lineages within the traditional Phymaturus palluma group we proposed to treat it as a natural group, containing within it the ranks of clade, subclade, and lineages, respectively. The palluma group is composed by the vociferator and the bibronii clades. The vociferator clade, composed of Chilean and Argentinean species, would be the most basal in the group. Within the bibronii clade, the roigorum subclade includes the Phymaturus verdugo lineage, whereas the mallimaccii subclade would consist of 13 terminal taxa, for which three Chilean species have been added. In this study, morphological apomorphies are identified for all clades and the evolution of ‘male head melanism’ is discussed. © 2015 The Linnean Society of London  相似文献   

15.
Previous studies using the nuclear SSU rDNA and partial LSU rDNA have demonstrated that the euglenoid loricate taxa form a monophyletic clade within the photosynthetic euglenoid lineage. It was unclear, however, whether the loricate genera Trachelomonas and Strombomonas were monophyletic. In order to determine the relationships among the loricate taxa, SSU and LSU nuclear rDNA sequences were obtained for eight Strombomonas and 25 Trachelomonas strains and combined in a multigene phylogenetic analysis. Conserved regions of the aligned data set were used to generate maximum‐likelihood (ML) and Bayesian phylogenies. Both methods recovered a strongly supported monophyletic loricate clade with Strombomonas and Trachelomonas species separated into two sister clades. Taxa in the genus Strombomonas sorted into three subclades. Within the genus Trachelomonas, five strongly supported subclades were recovered in all analyses. Key morphological features could be attributed to each of the subclades, with the major separation being that all of the spine‐bearing taxa were located in two sister subclades, while the more rounded, spineless taxa formed the remaining three subclades. The separation of genera and subclades was supported by 42 distinct molecular signatures (33 in Trachelomonas and nine in Strombomonas). The morphological and molecular data supported the retention of Trachelomonas and Strombomonas as separate loricate genera.  相似文献   

16.
The establishment of epitypes (together with emended diagnoses) for seven species of Phacus Dujard. [Phacus oscillans G. A. Klebs, Phacus parvulus G. A. Klebs, Phacus pusillus Lemmerm., Phacus skujae Skvortzov, Phacus inflexus (Kisselew) Pochm., Phacus polytrophos Pochm., and Phacus smulkowskianus (Zakry?) Kusber] was achieved by literature studies, verification of morphological diagnostic features (cell size, cell shape), as well as molecular characters (SSU rDNA). The investigated Phacus species are mostly well distinguished morphologically, with an SSU rDNA interspecific sequence similarity of 95.1%–99.0% and an intraspecific sequence similarity of 99.0%–99.9%. Some of the phylogenetic relationships among the seven species have not been resolved, but the topology obtained indicates their assignment into two sister clades. The first clade is composed of two sister groups (P. parvulus and P. pusillus), while the second constitutes an assemblage of the remaining five species. The relationships between the clades remain unresolved.  相似文献   

17.
In this study, we re-describe the advertisement and territorial calls of Boana pardalis, carry out an acoustic comparison between the studied species and the other congeners of the B. faber group, and report for the first time the tympanic amplexus for the studied species. The advertisement call of B. pardalis can be used to supplement its diagnosis in the B. faber group based on temporal call traits, e.g. emission rate and emission pattern, as well as the call envelope.  相似文献   

18.
The hyolaryngeal apparatus includes the arytenoid, cricoid and hyoid cartilages, and varied sizes and shapes can be distinguished between species. Although the larynx is an important morphological structure for sound production in frogs, few studies describe the structures and processes of its parts in hylids. We studied the hyolaryngeal anatomy of both males and females of Scinax ruber (Laurenti, 1768), using clearing and double staining methods, comparing it with that of Scinax wandae (Pyburn and Fouquette, 1971), Scinax kennedyi (Pyburn, 1973) and other hylid species. We found that S. ruber has the largest arytenoid cartilage of any species of the subfamily Scinaxinae studied to date. We described both the laryngeal differences among three Scinax species and the interspecific variability in the shapes of the projections of the arytenoid in the males of these species. The taxonomic characters (presence/absence of processes of the cartilage of Santorini, oesophageal process or bronchial processes) described here can play a key role in differentiating these species from Scinax species and from other species. In addition, we want to contribute to the natural history and comparison of the larynges in Scinax and within the genus and the Hylidae.  相似文献   

19.
20.
A phylogenetic analysis of Euphorbiaceae sensu stricto is presented using sequences from rbcL, atpB, matK and 18S rDNA from 85 species and 83 genera. The combined analysis of four molecular markers resulted in only one most parsimonious tree and also generated new supported clades, which include Euphorbioideae + Acalyphoideae s.s., subclades A2 + A3, subclades A5 + A6 and a clade uniting subclades A2–A8 within Acalyphoideae s.s. A palisadal exotegmen is a possible synapomorphy for all the Euphorbiaceae, except for the subfamily Peroideae. The presence of vascular bundles in the inner integument and a thick inner integument were shown to be synapomorphies for the clade of inaperturate and articulated crotonoids and for the large clade of Euphorbioideae, Acalyphoideae s.s., inaperturate and articulated crotonoids, respectively. Characters of the aril and vascular bundles in the outer integument are discussed. The selected embryological characters were seen to be highly correlated with the molecular phylogeny. When the results of molecular phylogenetic analysis of a previous study and this study were adjusted along with the selected embryological characters, all clades within Euphorbiaceae were supported except for a clade comprising Euphorbioideae + Acalyphoideae s.s. + inaperturate crotonoids + articulated crotonoids + Adenoclineae s.l. and a clade uniting subclades A4–A8 within Acalyphoideae s.s. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

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