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Spartak N Litvinchuk - One of the best experts on this subject based on the ideXlab platform.
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Natural Autotriploidy in the Danube Newt, Triturus dobrogicus (Salamandridae)
Russian Journal of Herpetology, 2013Co-Authors: Spartak N Litvinchuk, Jury M. Rosanov, L. J. BorkinAbstract:A case of natural autotriploidy in Triturus dobrogicus from Transcarpathian Province (Ukraine) is described. This is the first record of polyploidy for the species.
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Spontaneous Triploidy in the Crested Newt, Triturus cristatus (Salamandridae)
Russian Journal of Herpetology, 2011Co-Authors: Leo J. Borkin, Spartak N Litvinchuk, Jury M. RosanovAbstract:A triploid male was found among the offspring of a female of Triturus cristatus which was collected in the Ukrainian Transcarpathians. It is the first record of spontaneous triploidy for the species, and for salamanders of the former Soviet Union in general.
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Comparative Morphology of Trunk and Sacral Vertebrae of Tailed Amphibians of Russia and Adjacent Countries
Russian Journal of Herpetology, 2011Co-Authors: Vyacheslav Yu. Ratnikov, Spartak N LitvinchukAbstract:Trunk and sacral vertebrae of three species of the family Hynobiidae ( Onychodactylus fischeri , Ranodon sibiricus , and Salamandrella keyserlingii ) and nine species of the family Salamandridae ( Lissotriton montandoni , Lissotriton vulgaris , Mertensiella caucasica , Mesotriton alpestris , Ommatotriton ophryticus , Salamandra salamandra , Triturus cristatus , Triturus dobrogicus , and Triturus karelinii ) were studied. Analysis of individual variation of vertebrae of these species along the axial column and systematic descriptions of these species are given. Our comparative analysis revealed that all species studied have peculiarities which allow diagnosing them. Geographic variation in height of neurapophysis was found in Triturus karelinii . Specimens of the species from the Crimea and the Balkans have low neurapophyses, and newts from eastern Georgia and Dagestan are characterized by high ones.
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ATLANTAL VERTEBRAE OF TAILED AMPHIBIANS OF RUSSIA AND ADJACENT COUNTRIES
Russian Journal of Herpetology, 2011Co-Authors: Vyacheslav Yu. Ratnikov, Spartak N LitvinchukAbstract:Morphology of atlantal vertebrae of four species of the family Hynobiidae ( Onychodactylus fischeri , Ranodon sibiricus , Salamandrella keyserlingii , and Salamandrella schrenkii ) and nine species of the family Salamandridae ( Lissotriton montandoni , Lissotriton vulgaris , Mertensiella caucasica , Mesotriton alpestris , Ommatotriton ophryticus , Salamandra salamandra , Triturus cristatus , Triturus dobrogicus , and Triturus karelinii ) were studied. Analysis of variation of vertebrae of these species and systematic descriptions of these species are given. Our comparative analysis revealed that all species studied have peculiarities which allow diagnosing them.
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A Molecular Assessment of Phylogenetic Relationships and LineageDiversification Within the Family Salamandridae (Amphibia, Caudata)
Molecular Phylogenetics and Evolution, 2005Co-Authors: David W. Weisrock, Spartak N Litvinchuk, Theodore J. Papenfuss, J. Robert Macey, Rosa Polymeni, Ismail H. Ugurtas, Ermi Zhao, Allan LarsonAbstract:Phylogenetic relationships among species of the salamanderfamily Salamandridae are investigated using nearly 3000 nucleotide basesof newly reported mitochondrial DNA sequence data from the mtDNA genicregion spanning the genes tRNALeu-COI. This study uses nearlycomprehensive species-level sampling to provide the first completephylogeny for the Salamandridae. Deep phylogenetic relationships amongthe three most divergent lineages in the family Salamandrina terdigitata,a clade comprising the "True" salamanders, and a clade comprising allnewts except S. terdigitata are difficult to resolve. However, mostrelationships within the latter two lineages are resolved with robustlevels of branch support. The genera Euproctus and Triturus arestatistically shown to be nonmonophyletic, instead each contains adiverse set of lineages positioned within the large newt clade. The genusParamesotriton is also resolve as a nonmonophyletic group, with the newlydescribed species P. laoensis constituting a divergent lineage placed ina sister position to clade containing all Pachytriton species and allremaining Paramesotriton species. Sequence divergences between P.laoensis and other Paramesotriton species are as great as those comparingP. laoensis and species of the genera Cynops and Pachytriton. Analyses oflineage diversification across the Salamandridae indicate that, despiteits exceptional diversity, lineage accumulation appears to have beenconstant across time, indicating that it does not represent a truespecies radiation.
Ines Van Bocxlaer - One of the best experts on this subject based on the ideXlab platform.
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high pheromone diversity in the male cheek gland of the red spotted newt notophthalmus viridescens Salamandridae
BMC Evolutionary Biology, 2015Co-Authors: Sunita Janssenswillen, Bert Willaert, Dag Treer, Wim Vandebergh, Franky Bossuyt, Ines Van BocxlaerAbstract:Male salamanders (Urodela) often make use of pheromones that are produced in sexually dimorphic glands to persuade the female into courtship and mating. The mental gland of lungless salamanders (Plethodontidae) and dorsal cloacal glands (or abdominal glands) of newts (Salamandridae) have been particularly well studied in that respect. In both families, sodefrin precursor-like factor (SPF) proteins have been identified as major components of the courtship pheromone system. However, similar to plethodontids, some newts also make use of subtle head glands during courtship, but few pheromones have been characterized from such structures. Males of red-spotted newts (Notophthalmus viridescens, Salamandridae) have both cloacal and cheek (genial) glands, and are known to apply secretions to the female’s nose by both tail-fanning and cheek-rubbing. Here we combined transcriptomic and phylogenetic analyses to investigate the presence, diversity and evolution of SPF proteins in the cloacal and cheek glands of this species. Our analyses indicate that the cheek glands of male N. viridescens produce a similar amount and diversity of SPF isoforms as the cloacal glands in this species. Expression in other tissues was much lower, suggesting that both male-specific courtship glands secrete SPF pheromones during courtship. Our phylogenetic analyses show that N. viridescens expresses a combination of isoforms that stem from four highly diverged evolutionary lineages of SPF variants, that together form a basis for the broad diversity of SPF precursors in the breeding glands. The similar SPF expression of cheek and cloacal glands suggests that this protein family is used for pheromone signalling through cheek rubbing in the red-spotted newt. Since several male salamandrids in other genera have comparable head glands, SPF application via other glands than the cloacal glands may be more widespread than currently appreciated in salamandrids.
Sunita Janssenswillen - One of the best experts on this subject based on the ideXlab platform.
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male courtship pheromones induce cloacal gaping in female newts Salamandridae
PLOS ONE, 2016Co-Authors: Sunita Janssenswillen, Franky BossuytAbstract:Pheromones are an important component of sexual communication in courting salamanders, but the number of species in which their use has been demonstrated with behavioral evidence remains limited. Here we developed a behavioral assay for demonstrating courtship pheromone use in the aquatically courting Iberian ribbed newt Pleurodeles waltl. By performing an in-depth study of the courtship behavior, we show that females invariably open their cloaca (cloacal gaping) before engaging in pinwheel behavior, the circling movement that is the prelude to spermatophore uptake. In contrast, cloacal gaping was not observed in failed courtships, where females escaped or displayed thanatosis. Since gaping mainly occurred during male amplexus and cloacal imposition, which is the obvious period of pheromone transfer, we next investigated whether male courtship water (i.e., water holding courtship pheromones) alone was able to induce this reaction in females. These tests showed that courtship water induced cloacal gaping significantly more than water, even in the absence of a male. Cloacal gaping thus provides a simple and robust test for demonstrating courtship pheromone use in the Iberian ribbed newt. Since opening the cloaca is an essential prerequisite for spermatophore pick-up in all internally fertilizing salamanders, we hypothesize that variations on this assay will also be useful in several other species.
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high pheromone diversity in the male cheek gland of the red spotted newt notophthalmus viridescens Salamandridae
BMC Evolutionary Biology, 2015Co-Authors: Sunita Janssenswillen, Bert Willaert, Dag Treer, Wim Vandebergh, Franky Bossuyt, Ines Van BocxlaerAbstract:Male salamanders (Urodela) often make use of pheromones that are produced in sexually dimorphic glands to persuade the female into courtship and mating. The mental gland of lungless salamanders (Plethodontidae) and dorsal cloacal glands (or abdominal glands) of newts (Salamandridae) have been particularly well studied in that respect. In both families, sodefrin precursor-like factor (SPF) proteins have been identified as major components of the courtship pheromone system. However, similar to plethodontids, some newts also make use of subtle head glands during courtship, but few pheromones have been characterized from such structures. Males of red-spotted newts (Notophthalmus viridescens, Salamandridae) have both cloacal and cheek (genial) glands, and are known to apply secretions to the female’s nose by both tail-fanning and cheek-rubbing. Here we combined transcriptomic and phylogenetic analyses to investigate the presence, diversity and evolution of SPF proteins in the cloacal and cheek glands of this species. Our analyses indicate that the cheek glands of male N. viridescens produce a similar amount and diversity of SPF isoforms as the cloacal glands in this species. Expression in other tissues was much lower, suggesting that both male-specific courtship glands secrete SPF pheromones during courtship. Our phylogenetic analyses show that N. viridescens expresses a combination of isoforms that stem from four highly diverged evolutionary lineages of SPF variants, that together form a basis for the broad diversity of SPF precursors in the breeding glands. The similar SPF expression of cheek and cloacal glands suggests that this protein family is used for pheromone signalling through cheek rubbing in the red-spotted newt. Since several male salamandrids in other genera have comparable head glands, SPF application via other glands than the cloacal glands may be more widespread than currently appreciated in salamandrids.
Giuseppina Barsacchi - One of the best experts on this subject based on the ideXlab platform.
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Molecular cytogenetics of the ribosomal (18S + 28S and 5S) DNA loci in primitive and advanced urodele amphibians.
Genome, 1993Co-Authors: Stefania De Lucchini, Irma Nardi, Giuseppina Barsacchi, Renata Batistoni, F. AndronicoAbstract:In the present work we performed a cytogenetic analysis of the ribosomal (18S + 28S and 5S) loci in amphibian species belonging to the advanced family Salamandridae (genera Triturus, Salamandra, and Salamandrina) and in the primitive hynobiid Salamandrella keyserlingii (family Hynobiidae). In each analyzed karyotype the 5S rDNA sites appear to be stable, and definite in number, while an intraspecific variability both in number and chromosomal location of the 18S + 28S rDNA loci has been found in some Triturus species. In particular, an evolutionary trend toward a large intraspecific variability of the 18S + 28S rDNA loci has been found in the T. vulgaris species group. A structural analysis of the ribosomal repetition units demonstrates the occurrence of a length polymorphism within the 18S + 28S rDNA repeats in the examined species of the family Salamandridae; however, this polymorphism is rather limited, even in those Triturus species characterized by high intragenomic variability of the ribosomal sites...
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Two dispersed highly repeated DNA families of Triturus vulgaris meridionalis (Amphibia, Urodela) are widely conserved among Salamandridae
Chromosoma, 1991Co-Authors: Robert Vignali, Renata Batistoni, Filippo M. Rijli, Duccio Fratta, Federico Cremisi, Giuseppina BarsacchiAbstract:Two BamHI families of repeated sequences were characterized from the genome of the Italian smooth newt, Triturus vulgaris meridionalis (Amphibia, Urodela). The first family, which is divided into subfamilies, consists of tandemly arranged arrays whose basic repeat is around 398 bp long; these arrays are dispersed throughout the entire chromosome sets of the various species of Triturus tested. Moreover the family is widely conserved among Salamandridae, being detected by genomic DNA blotting of Notophthalmus viridescens, Taricha granulosa, Salamandrina terdigitata and Euproctus platycephalus . The second BamHI family is represented by a cloned sequence of 419 bp, which is dispersed in the chromosome set of several species of Triturus . The sequence is also conserved in S. terdigitata and in E. platycephalus but is not detectable in N. viridescens or T. granulosa . The cloned sequence is most probably only part of a longer unit interspersed within the Triturus genome.
Jan W. Arntzen - One of the best experts on this subject based on the ideXlab platform.
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Evolution of skull shape in the family Salamandridae (Amphibia: Caudata)
Journal of anatomy, 2017Co-Authors: Ana Ivanović, Jan W. ArntzenAbstract:We carried out a comparative morphometric analysis of 56 species of salamandrid salamanders, representing 19 out of 21 extant genera, with the aim of uncovering the major patterns of skull shape diversification, and revealing possible trends and directions of evolutionary change. To do this we used micro-computed tomography scanning and three-dimensional geometric morphometrics, along with a well-resolved molecular phylogeny. We found that allometry explains a relatively small amount of shape variation across taxa. Congeneric species of salamandrid salamanders are more similar to each other and cluster together producing distinct groups in morphospace. We detected a strong phylogenetic signal and little homoplasy. The most pronounced changes in the skull shape are related to the changes of the frontosquamosal arch, a unique feature of the cranial skeleton for the family Salamandridae, which is formed by processes arising from the frontal and squamosal bones that arch over the orbits. By mapping character states over the phylogeny, we found that a reduction of the frontosquamosal arch occurs independently in three lineages of the subfamily Pleurodelinae. This reduction can probably be attributed to changes in the development and ossification rates of the frontosquamosal arch. In general, our results are similar to those obtained for caecilian amphibians, with an early expansion into the available morphospace and a complex history characterizing evolution of skull shape in both groups. To evaluate the specificity of the inferred evolutionary trajectories and Caudata-wide trends in the diversity of skull morphology, information from additional groups of tailed amphibians is needed.
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A Bayesian approach on molecules and behavior: reconsidering phylogenetic and evolutionary patterns of the Salamandridae with emphasis on Triturus newts.
Journal of experimental zoology. Part B Molecular and developmental evolution, 2007Co-Authors: Sebastian Steinfartz, Saverio Vicario, Jan W. Arntzen, Adalgisa CacconeAbstract:The monophyly of European newts of the genus Triturus within the family Salamandridae has for decades rested on presumably homologous behavioral and morphological characters. Molecular data challenge this hypothesis, but the phylogenetic position of Triturus within the Salamandridae has not yet been convincingly resolved. We addressed this issue and the temporal divergence of Triturus within the Salamandridae with novel Bayesian approaches applied to DNA sequence data from three mitochondrial genes (12S, 16S and cytb). We included 38 salamandrid species comprising all 13 recognized species of Triturus and 16 out of 17 salamandrid genera. A clade comprising all the "Newts" can be separated from the "True Salamanders" and Salamandrina clades. Within the "Newts" well-supported clades are: Tylototriton-Pleurodeles, the "New World Newts" (Notophthalmus-Taricha), and the "Modern Eurasian Newts" (Cynops, Pachytriton, Paramesotriton=together the "Modern Asian Newts", Calotriton, Euproctus, Neurergus and Triturus species). We found that Triturus is a non-monophyletic species assemblage, which includes four groups that are themselves monophyletic: (i) the "Large-Bodied Triturus" (six species), (ii) the "Small-Bodied Triturus" (five species), (iii) T. alpestris and (iv) T. vittatus. We estimated that the last common ancestor of Triturus existed around 64 million years ago (mya) while the root of the Salamandridae dates back to 95 mya. This was estimated using a fossil-based molecular dating approach and an explicit framework to select calibration points that least underestimated their corresponding nodes. Using the molecular phylogeny we mapped the evolution of life history and courtship traits in Triturus and found that several Triturus-specific courtship traits evolved independently.
