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Previous efforts to reconstruct evolutionary history of Palearctic ground squirrels within the genus Spermophilus have primarily relied on a single mitochondrial marker for phylogenetic data. In this study, we present the first phylogeny with comprehensive taxon sampling of Spermophilus via a conventional multilocus approach utilizing five mitochondrial and five nuclear markers. Through application of the multispecies coalescent model, we constructed a species tree revealing four distinct clades that diverged during the Late Miocene. These clades are 1) S. alaschanicus and S. dauricus from East Asia; 2) S. musicus and S. pygmaeus from East Europe and northwestern Central Asia; 3) the subgenus Colobotis found across Central Asia and its adjacent regions and encompassing S. brevicauda, S. erythrogenys, S. fulvus, S. major, S. pallidicauda, S. ralli, S. relictus, S. selevini, and S. vorontsovi sp. nov.; and 4) a Central/Eastern Europe and Asia Minor clade comprising S. citellus, S. taurensis, S. xanthoprymnus, S. suslicus, and S. odessanus. The latter clade lacked strong support owing to uncertainty of taxonomic placement of S. odessanus and S. suslicus. Resolving relationships within the subgenus Colobotis, which radiated rapidly, remains challenging likely because of incomplete lineage sorting and introgressive hybridization. Most of modern Spermophilus species diversified during the Early-Middle Pleistocene (2.2-1.0 million years ago). We propose a revised taxonomic classification for the genus Spermophilus by recognizing 18 species including a newly identified one (S. vorontsovi sp. nov.), which is found only in a limited area in the southeast of West Siberia. Employing genome-wide single-nucleotide polymorphism genotyping, we substantiated the role of the Ob River as a major barrier ensuring robust isolation of this taxon from S. erythrogenys. Despite its inherent limitations, the traditional multilocus approach remains a valuable tool for resolving relationships and can provide important insights into otherwise poorly understood groups. It is imperative to recognize that additional efforts are needed to definitively determine phylogenetic relationships between certain species of Palearctic ground squirrels.
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Introgresión Genética , Sciuridae , Animales , Siberia , Filogenia , Sciuridae/genética , AsiaRESUMEN
The spatial genetic structure is a topical issue in the studies of various aspects of ecology and evolution. Using the multilocus autocorrelation method with hypervariable microsatellite genetic markers, we investigated a fine-scale pattern of genetic structure in 5 local populations of the common shrew Sorex araneus separated by distances of 300-1000 m (the Moscow chromosomal race). Spatial genetic autocorrelation analysis based on 5 microsatellite loci (expected heterozygosity >0.79) with 90 alleles revealed a consistent pattern of significant positive genetic structure. By testing the autocorrelation at multiple scales from 25 to 500 m, we found that positive spatial genetic structure is detectable in distance classes of <500 m. The weaker spatial genetic structure positively correlated with a higher ratio of nonresident individuals to residents' activity (number of captures). In contrast to nonresident animals, the residents demonstrated prominent genetic structure. Genetic difference (FST ) between the populations was significant (0.016-0.051) and comparable with that between populations of different races analyzed previously (0.016-0.038). FST was not associated with geographic distance. These demographic patterns allowed us to propose a scheme of genetic-structure dynamics involving periodic appearance of more related local groups and renewal of allelic profiles from а common pool where the alleles are mixed. The scheme predicts fluctuating genetic structure and random similar differences among local populations.
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Eulipotyphla , Musarañas , Animales , Musarañas/genética , Eulipotyphla/genética , Repeticiones de Microsatélite/genética , Variación GenéticaRESUMEN
Two new species of the genus Isochlora Staudinger, 1882 are described: I. hreblayi Volynkin, Tth, Titov & Saldaitis, sp. n. (western Mongolia) and I. kozlovi Volynkin, Titov, Matov & Saldaitis, sp. n. (Qinghai Province, China). The type species of the genus-group names Chamyla Staudinger, 1900 and Grumia Alphraky, 1892 (I. arctomys Alphraky, 1897 and I. flora (Alphraky, 1892), respectively) are examined, and their synonymy with Isochlora is revised. The synonymy of Chamyla idia Staudinger, 1900 with Isochlora arctomys Alphraky, 1897 is revised as junior synonymies. Lectotypes are designated for Isochlora arctomys Alphraky, 1897, Chamyla idia Staudinger, 1900 and Grumia flora Alphraky, 1892. Isochlora intricans (Alphraky, 1882) is reported from Kazakhstan for the first time. Adults as well as male and female genitalia are illustrated.
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Lepidópteros , Mariposas Nocturnas , Masculino , Femenino , Animales , Mongolia , Distribución Animal , ChinaRESUMEN
A new species of the genus Victrix Staudinger, 1879, V. akbet Volynkin, Titov Cernila, sp. nov. is described from Kazakhstan. The new species belongs to the subgenus Poliobrya Hampson, 1908. A diagnostic comparison is made with V. frigidalis Varga Ronkay, 1991, V. fabiani Varga Ronkay, 1989 and V. umovii (Eversmann, 1846). The adults and male and female genitalia of the new and related species are illustrated.
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Lepidópteros , Mariposas Nocturnas , Distribución Animal , Estructuras Animales , Animales , Tamaño Corporal , Femenino , Kazajstán , Masculino , Tamaño de los ÓrganosRESUMEN
The utility of DNA Barcoding for species identification and discovery has catalyzed a concerted effort to build the global reference library; however, many animal groups of economical or conservational importance remain poorly represented. This study aims to contribute DNA barcode records for all ground squirrel species (Xerinae, Sciuridae, Rodentia) inhabiting Eurasia and to test efficiency of this approach for species discrimination. Cytochrome c oxidase subunit 1 (COI) gene sequences were obtained for 97 individuals representing 16 ground squirrel species of which 12 were correctly identified. Taxonomic allocation of some specimens within four species was complicated by geographically restricted mtDNA introgression. Exclusion of individuals with introgressed mtDNA allowed reaching a 91.6% identification success rate. Significant COI divergence (3.5-4.4%) was observed within the most widespread ground squirrel species (Spermophilus erythrogenys, S. pygmaeus, S. suslicus, Urocitellus undulatus), suggesting the presence of cryptic species. A single putative NUMT (nuclear mitochondrial pseudogene) sequence was recovered during molecular analysis; mitochondrial COI from this sample was amplified following re-extraction of DNA. Our data show high discrimination ability of 100 bp COI fragments for Eurasian ground squirrels (84.3%) with no incorrect assessments, underscoring the potential utility of the existing reference librariy for the development of diagnostic 'mini-barcodes'.
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Núcleo Celular/genética , Código de Barras del ADN Taxonómico , Hibridación Genética , Mitocondrias/genética , Seudogenes/genética , Sciuridae/clasificación , Sciuridae/genética , Animales , ADN Mitocondrial/genética , Variación GenéticaRESUMEN
A new species of the genus Perigrapha, P. yasawii sp. n. is described from Syrdarya river valley, South Kazakhstan. The adults and male genitalia of the new and related species are illustrated.
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Mariposas Nocturnas/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Tamaño Corporal , Femenino , Kazajstán , Masculino , Mariposas Nocturnas/anatomía & histología , Mariposas Nocturnas/crecimiento & desarrollo , Tamaño de los ÓrganosRESUMEN
The Holarctic genus Euchalcia Hübner, [1821] belongs to the tribe Plusiini of the subfamily Plusiinae. The genus is one of the largest in the Plusiinae, comprising about 54 described species. The systematics of Eurasian and North African members of the genus was recently revised (Ronkay et al. 2008). In June 2013, in the course of faunistic studies on Noctuidae of the Tarbagatai Mts. (East Kazakhstan), a long series of an undescribed species of the genus was collected. Two additional specimens from the Dzhungarsky Alatau Mts. (South-East Kazakhstan) were found in the collection of the Siberian Zoological Museum (Novosibirsk). The species is described herein as new. It belongs to the E. inconspicua group within the E. inconspicua species-complex (Ronkay et al. 2008). The E. inconspicua group comprises two described species only: E. inconspicua (Graeser, 1892) and E. anthea L. Ronkay, G. Ronkay & Behounek, 2008. The new species is the northernmost member of the group. Institutional acronyms are as follows: AVB-coll. A.V. Volynkin, Barnaul, Russia; MCK-coll. M. Cernila, Kamnik, Slovenia; NHMW-Naturhistorisches Museum, Vienna, Austria; STP-coll. S.V. Titov, Pavlodar, Kazakhstan; SZMN-Siberian Zoological Museum of the Institute of Animal Systematic and Ecology of the Siberian Branch of the Russian Academy of Sciences (Novosibirsk, Russia), ZISP-Zoological Institute of Russian Academy of Sciences, St. Petersburg, Russia.
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Mariposas Nocturnas/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Animales , Ecosistema , Femenino , Kazajstán , Masculino , Mariposas Nocturnas/anatomía & histología , Federación de Rusia , EsloveniaRESUMEN
Inertial effects in the rotational brownian motion in space of a rigid dipolar rotator (needle) in a uniaxial potential biased by an external field giving rise to asymmetry are treated via the infinite hierarchy of differential-recurrence relations for the statistical moments (orientational correlation functions) obtained by averaging the Euler-Langevin equation over its realizations in phase space. The solutions of this infinite hierarchy for the dipole correlation function and its characteristic times are obtained using matrix continued fractions showing that the model simultaneously predicts both slow overbarrier (or interwell) relaxation at low frequencies accompanied by intermediate frequency Debye relaxation due to fast near-degenerate motion in the wells of the potential (intrawell relaxation) as well as the high frequency resonance (Poley) absorption due to librations of the dipole moments. It is further shown that the escape rate of a brownian particle from a potential well as extended to the Kramers turnover problem via the depopulation factor yields a close approximation to the longest (overbarrier) relaxation time of the system. For zero and small values of the bias field parameter h, both the dipole moment correlation time and the longest relaxation time have Arrhenius behavior (exponential increase with increasing barrier height). While at values of h in excess of a critical value however far less than that required to achieve nucleation, the Arrhenius behavior of the correlation time disappears.
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The anomalous translational diffusion including inertial effects of nonlinear Brownian oscillators in a double well potential V(x)=ax{2}/2+bx{4}/4 is considered. An exact solution of the fractional Klein-Kramers (Fokker-Planck) equation is obtained allowing one to calculate via matrix continued fractions the positional autocorrelation function and dynamic susceptibility describing the position response to a small external field. The result is a generalization of the solution for the normal Brownian motion in a double well potential to fractional dynamics (giving rise to anomalous diffusion).
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Nonlinear transient responses of polar polarizable particles (macromolecules) diluted in a nonpolar solvent to a sudden change in magnitude of a strong external dc field are evaluated using the anisotropic noninertial rotational diffusion model. The relaxation functions and relaxation times appropriate to the transient dynamic Kerr effect and nonlinear dielectric relaxation are calculated by solving the infinite hierarchy of differential-recurrence equations for statistical moments (ensemble averages of the Wigner D functions). The calculations involve matrix continued fractions, which ultimately yield the exact solution of the infinite hierarchy of differential-recurrence relations for the first- and second-order transient responses.
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It is shown how the rotational diffusion model of polar molecules (which may be described in microscopic fashion as the diffusion limit of a discrete time random walk on the surface of the unit sphere) may be extended to anomalous nonlinear dielectric relaxation and the dynamic Kerr effect by using a fractional kinetic equation. This fractional kinetic equation (obtained via a generalization of the noninertial kinetic equation of conventional rotational diffusion to fractional kinetics to include anomalous relaxation) is solved using matrix continued fractions yielding the complex nonlinear dielectric susceptibility and the Kerr function of an assembly of rigid dipolar particles acted on by external superimposed dc E0 and ac E1(t)=E1 cos omegat electric fields of arbitrary strengths. In the weak field limit, analytic equations for nonlinear response functions are also derived.
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The Kramers theory of the escape rate of a Brownian particle from a potential well as extended by Mel'nikov and Meshkov is used to evaluate the relaxation times and the dynamic susceptibility for the rotational Brownian motion of fixed axis rotators in an asymmetric double-well potential. An expression for the escape rate valid for all values of the dissipation including the very low damping (VLD), very high damping (VHD), and crossover regimes is derived. It is shown that this expression provides a good asymptotic estimate of the inverse of the smallest nonvanishing eigenvalue lambda(1) of the underlying Fokker-Planck operator calculated by using the matrix-continued fraction method. For low barriers, where the Mel'nikov and Meshkov approach is not applicable, analytic equations for the correlation time tau( parallel) of the longitudinal dipole correlation function in the VLD and VHD limits are derived and a simple extrapolating equation valid for all values of the damping is proposed.
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The longitudinal and transverse components of the complex dielectric susceptibility tensor of an assembly of dipolar molecules rotating in an asymmetric double-well potential are evaluated using a fractional rotational diffusion equation (based on the diffusion limit of a fractal time random walk) for the distribution function of orientations of the molecules on the surface of the unit sphere. The calculation is the fractional analog of the Debye theory of orientational relaxation in the presence of external and mean field potentials (excluding inertial effects). Exact and approximate (based on the exponential separation for normal diffusion of the time scales of the intrawell and overbarrier relaxation processes associated with the bistable potential) solutions for the dielectric dispersion and absorption spectra are obtained. It is shown that a knowledge of the characteristic relaxation times for normal rotational diffusion is sufficient to predict accurately the anomalous dielectric relaxation behavior of the system for all time scales of interest. The model explains the anomalous (Cole-Cole-like) relaxation of complex dipolar systems, where the anomalous exponent differs from unity (corresponding to the normal dielectric relaxation), i.e., the relaxation process is characterized by a broad distribution of relaxation times (e.g., in glass-forming liquids).
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It is shown how the Debye rotational diffusion model of dielectric relaxation of polar molecules (which may be described in microscopic fashion as the diffusion limit of a discrete time random walk on the surface of the unit sphere) may be extended to yield the empirical Havriliak-Negami (HN) equation of anomalous dielectric relaxation from a microscopic model based on a kinetic equation just as in the Debye model. This kinetic equation is obtained by means of a generalization of the noninertial Fokker-Planck equation of conventional Brownian motion (generally known as the Smoluchowski equation) to fractional kinetics governed by the HN relaxation mechanism. For the simple case of noninteracting dipoles it may be solved by Fourier transform techniques to yield the Green function and the complex dielectric susceptibility corresponding to the HN anomalous relaxation mechanism.
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The extension of the Kramers theory of the escape rate of a Brownian particle from a potential well to the entire range of damping proposed by Mel'nikov and Meshkov [J. Chem, Phys. 85, 1018 (1986)] is applied to the rotational Brownian motion of fixed axis rotators in a double well cosine potential. The procedure yields an expression for the Kramers escape rate valid for all values of the dissipation including the very low damping (VLD), very high damping (VHD), and crossover regimes. This equation provides a good asymptotic estimate of the correlation time tau per pendicular of the longitudinal dipole moment correlation function calculated by solving the underlying Langevin equation using the matrix-continued fraction method. Moreover, for low barriers, where the Mel'nikov and Meshkov approach is not applicable, analytic equations for tau in the VLD and VHD limits are derived and a simple extrapolating equation that is valid for all values of the damping is proposed.
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The linear dielectric response of an assembly of noninteracting symmetrical top molecules (each of which is free to rotate in space) is evaluated in the context of fractional dynamics. The infinite hierarchy of differential-recurrence relations for the relaxation functions appropriate to the dielectric response is derived by using the underlying inertial fractional Klein-Kramers equation. On solving this hierarchy in terms of matrix continued fractions (as in the normal rotational diffusion), the complex dynamic susceptibility is obtained and is calculated for typical values of the model parameters. For the limiting case of spherical top molecules, the solution is obtained in terms of an ordinary continued fraction. It is shown that the model can reproduce nonexponential anomalous dielectric relaxation behavior at low frequencies (omegatau
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Exact and approximate solutions of the fractional diffusion equation for an assembly of fixed-axis dipoles are derived for anomalous noninertial rotational diffusion in a double-well potential. It is shown that knowledge of three time constants characterizing the normal diffusion, viz., the integral relaxation time, the effective relaxation time, and the inverse of the smallest eigenvalue of the Fokker-Planck operator, is sufficient to accurately predict the anomalous relaxation behavior for all time scales of interest.
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The linear dielectric response of an assembly of noninteracting linear (needlelike) dipole molecules (each of which is free to rotate in space) is evaluated in the context of fractional dynamics. The infinite hierarchy of differential-recurrence relations for the relaxation functions appropriate to the dielectric response is derived by using the underlying inertial fractional Fokker-Planck (fractional Klein-Kramers) equation. On solving this hierarchy in terms of continued fractions (as in the normal rotational diffusion), the complex dynamic susceptibility is obtained and is calculated for typical values of the model parameters. It is shown that the model can reproduce nonexponential anomalous dielectric relaxation behavior at low frequencies (omega tau< or =1, where tau is the Debye relaxation time) and the inclusion of inertial effects ensures that optical transparency is regained at very high frequencies (in the far infrared region) so that Gordon's sum rule for integral dipolar absorption is satisfied.