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1.
A lower jaw of Stephanorhinus kirchbergensis from the Mus Khaya locality on the Yana River in Yakutia is described. This jaw was previously designated as a paratype of Coelodonta jacuticus, but morphological and morphometric analysis has shown that it actually belongs to a typical S. kirchbergensis. Morphometric parameters of the holotype (skull) of C. jacuticus fall within the range of intraspecific variation of C. antiquitatis. The same results of a morphometric study were obtained for the subspecies Coelodonta antiquitatis pristinus and C. a. humilis. This suggests that C. jacuticus, Coelodonta antiquitatis pristinus, and C. a. humilis are invalid taxa which should be regarded as junior synonyms of C. antiquitatis. The find of S. kirchbergensis in northern Yakutia is the northernmost occurrence of this species.  相似文献   

2.
The data on the fauna of blackflies of the tribe Simuliini (Diptera: Simuliidae) of the Sakha Republic (Yakutia) comprising the available literature, collections of the Zoological Institute of the Russian Academy of Sciences, and new material collected in Yakutia were analyzed. Three new species were recorded in the fauna of Yakutia: Archesimulium polare Rubzov, 1940, A. splendidum Rubzov, 1940, and A. tumulosum Rubzov, 1956. Distribution of 11 species was clarified. Processing of the collected material confirmed the presence of 9 blackfly species previously known from Yakutia. On the whole, the blackfly fauna of the region comprises 27 species.  相似文献   

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Theilopedothrips zur Strassen, 1995 with the single species Theilopedothrips pilosus (Uzel, 1895) is recorded for the first time for Siberia from Central Yakutia.  相似文献   

5.
The variety of life forms and the structure of individuals and ontomorphogenesis of T. extremus, T. indigirkensis, T. brevipetiolatus, and T. pavlovii under the conditions of Yakutia have been studied. It has been established that the formation of two life forms and three types of biomorphs is characteristic for the species: a monocentric vegetatively immobile dwarf subshrub (T. extremus), an implicitly polycentric vegetatively semimobile dwarf subshrub and dwarf shrub (T. indigirkensis and T. brevipetiolatus respectively), and an obviously polycentric vegetatively mobile dwarf subshrub (T. pavlovii). The basis of the adult shrub is a monopodially sympodially growing compound skeletal axis which differs in individuals of Thymus by the method of growth and position in space. An analysis of the development of species in Yakutia allowed us to identify common and specific features. Common features for the species are the predominance of the dwarf subshrub living form and its morphological plasticity, a small variety and shortening of the morphogenesis phases, a shallow rejuvenation of the ramets, a prolonged monopodial growth of shoots (up to 10 years), and the predominance of rosette shoots in the structure of the individual. Differences are revealed depending on the conditions of specific habitats of species. When T. extremus grows on a flat surface and high sludge, a dense primary shrub is formed. In the free areas of the substrate with stepwise depressions of the microrelief, the primary shrub T. extremus is loose. In T. brevipetiolatus, which grows in the steppe on the hillside, the structure of the individual is formed only by rosette shoots, their prolonged monopodial growth is maintained due to the preservation (for 1–2 years) of dry leaves. For T. pavlovii growing on a mossy substrate, this is the characteristic lodging of shoots, their intensive rooting and strengthening of vegetative mobility, and a reduction in the duration of ontogenesis of individuals due to the rapid decay of maternal structures. The revealed features of Thymus development are the mechanisms of morphological adaptation, which provide species survival in different environmental conditions of Yakutia.  相似文献   

6.
A comprehensive analysis of the diversity of Yakutian lamellicorn beetles is provided. A total of 54 species from 18 genera, 14 tribes, 14 subfamilies, and 5 families are revealed. The family Ochodaeidae Mulsant & Rey, 1871, the genus Codocera Eschscholtz, 1821, and six species, namely Codocera ferruginea (Eschscholtz, 1818), Aegialia friebi Balthasar, 1935, A. kamtschatica Motschulsky, 1860, Aphodius ater (De Geer, 1774), A. pusillus Herbst, 1789, and A. haemorrhoidalis (Linnaeus, 1758), are recorded in the fauna of Yakutia for the first time. The ecological and zoogeographic features of the Scarabaeoidea of the region are considered. Data on the trophic specialization, phenology and spatial distribution of the species are given.  相似文献   

7.
The feeding habits and trophic ecology of Mustelus lunulatus and Mustelus henlei in the central coast of the Colombian Pacific were evaluated and compared to determine whether there was trophic niche overlap or resource partitioning between these two sympatric shark species. A total of 59 prey items were identified and grouped into 10 taxonomic categories. Mustelus lunulatus fed in large proportion on Stomatopoda and Brachyura, whereas M. henlei fed almost exclusively on Teleostei. Dendrobranchiata, Cephalopoda, Anomura and Polychaeta complemented the diets of both species. There were significant differences in diet between the two species, and there was an ontogenetic diet shift in Mustelus lunulatus, with Stomatopoda being the main prey item of juveniles and Brachyura the main prey item of adults. Dietary overlap (by sex and size) was low between species, but it was high for each species, with significant overlap between juveniles and adults of M. lunulatus and M. henlei, and between males and females of M. henlei. There were differences in the trophic levels of the species, sexes and sizes. This study suggests there is food resource partitioning, and differing ecological function of the two Mustelus species in the food web of the study area.  相似文献   

8.
The world fauna comprises 134 species from 52 genera of gall midges associated with plants of the order Pinales (3 families, 16 genera and 74 species); 14 genera are specific to Pinales. The distribution of genera and species of gall midges over host plant taxa is described. The Holarctic genus Kaltenbachiola comprises four species all developing in the spruce (Picea spp.) cones. Earlier, K. strobi (Winnertz), widely distributed in Europe, was the only species known in the Palaearctic. A new species Kaltenbachiola anastasiae sp. n. is described, which damages cones of Picea obovata in Central Yakutia. The phylogenetic relationships of Kaltenbachiola with close genera specific to Pinales are characterized, and an updated diagnosis of the genus with additional morphometric parameters and keys to the pine-specific genera of the tribe Dasineurini and to species of the genus Kaltenbachiola are given. The host associations and specific traits of biology and distribution of Kaltenbachiola species are considered.  相似文献   

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It was shown that permanent (B = 50 μT, horizontal plane, direction to the north) and alternating magnetic fields (North–South direction) exerted influences on seed germination as well as on cytological and biochemical features of seedlings characteristic of investigated species (Lepidium apetalum, Artemisia vulgaris, A. jacutica, and A. dracunculus) of wild plants growing in Central Yakutia. Under the effect of permanent magnetic field (MF), germinating capacity of seeds decreased (except for A. vulgaris), whereas alternating MF of different frequencies improved their germinating capacity, except for L. apetalum and A. jacutica at frequencies of 200 and 300 Hz, respectively. Under permanent MF, the rate of lipid peroxidation in the tissues of the seedlings decreased, whereas the content of low molecular weight antioxidants rose; when the plants were exposed to an alternating magnetic field, the content of MDA and peroxidase activity increased, and the content of low molecular weight antioxidants followed an ambiguous pattern.  相似文献   

11.
Understanding the factors limiting population growth is crucial for species management and conservation. We assessed the effects of seed and microsite limitation, along with climate variables, on Helianthemum squamatum, a gypsum soil specialist, in two sites in central Spain. We evaluated the effects of experimental seed addition and soil crust disturbance on H. squamatum vital rates (survival, growth and reproduction) across four years. We used this information to build integral projection models (IPMs) for each combination of management (seed addition or soil disturbance), site and year. We examined differences in population growth rate (λ) due to management using life table response experiments. Soil crust disturbance increased survival of mid to large size individuals and germination. Contributions to λ of positive individual growth (progression) and negative individual growth (retrogression) due to managements varied among years and sites. Soil crust disturbance increased λ in the site with the highest plant density, and seed addition had a moderate positive effect on λ in the site with lowest plant density. Population growth rate (λ) decreased by half in the driest year. Differences in management effects between sites may represent a shift from seed to microsite limitation at increasing densities. This shift underscores the importance of considering what factors limit population growth when selecting a management strategy.  相似文献   

12.
Kelp forests dominate temperate and polar rocky coastlines and represent critical marine habitats because they support elevated rates of primary and secondary production and high biodiversity. A major threat to the stability of these ecosystems is the proliferation of non-native species, such as the Japanese kelp Undaria pinnatifida (‘Wakame’), which has recently colonised natural habitats in the UK. We quantified the abundance and biomass of U. pinnatifida on a natural rocky reef habitat over 10 months to make comparisons with three native canopy-forming brown algae (Laminaria ochroleuca, Saccharina latissima, and Saccorhiza polyschides). We also examined the biogenic habitat structure provided by, and epibiotic assemblages associated with, U. pinnatifida in comparison to native macroalgae. Surveys conducted within the Plymouth Sound Special Area of Conservation indicated that U. pinnatifida is now a dominant and conspicuous member of kelp-dominated communities on natural substrata. Crucially, U. pinnatifida supported a structurally dissimilar and less diverse epibiotic assemblage than the native perennial kelp species. However, U. pinnatifida-associated assemblages were similar to those associated with Saccorhiza polyschides, which has a similar life history and growth strategy. Our results suggest that a shift towards U. pinnatifida dominated reefs could result in impoverished epibiotic assemblages and lower local biodiversity, although this could be offset, to some extent, by the climate-driven proliferation of L. ochroleuca at the poleward range edge, which provides complex biogenic habitat and harbours relatively high biodiversity. Clearly, greater understanding of the long-term dynamics and competitive interactions between these habitat-forming species is needed to accurately predict future biodiversity patterns.  相似文献   

13.
We described the life cycles of 17 riffle-dwelling mayfly species in a central Japanese stream. Both species of Baetidae (Alainites yoshinensis Gose and Baetis thermicus Uéno) and two of nine species of Heptageniidae (Ecdyonurus scalaris Kluge and Epeorus latifolium Uéno/l-nigrus Matsumura) in this stream were multivoltine (more than one generation per year). Seven other heptageniid species (two unidentified species of Cinygmula, Epeorus aesculus Imanishi, E. curvatulus Matsumura, E. ikanonis Takahashi, E. napaeus Imanishi, and Rhithrogena japonica Uéno) and all six species of Ephemerellidae [Cincticostella elongatula (McLachlan), C. nigra (Uéno), Drunella basalis (Imanishi), D. ishiyamana Matsumura, D. sachalinensis (Matsumura), and D. trispina (Uéno)] were essentially univoltine.  相似文献   

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The muscles of the male genitalia were studied for the first time in two species endemic to the Oriental zoogeographical region, namely Curetis bulis from the subfamily Curetinae (Lycaenidae) and Paralaxita damajanti from the tribe Abisarini (Riodinidae). Both taxa possess a common plan of musculature reflected in the positions of muscles m1, m2(10), m5(7), m7(6), m21, and m28. Two new autapomorphies of Curetis bulis were discovered: the splitting of m4 into two muscles and a shift of the attachment site of one of these muscles onto the dorsal area of the anellus. Apomorphic differences in the position of the genital muscles were found between Paralaxita damajanti and the previously studied Polycaena tamerlana from the family Riodinidae. A new synapomorphy between the latter two species, namely splitting of the aedeagus protractors m6(5), was also found.  相似文献   

16.
As traditionally circumscribed, Cuscuta sect. Denticulatae is a group of three parasitic plant species native to the deserts of Western USA (Cuscuta denticulata, Cuscuta nevadensis) and the central region of Baja California, Mexico (Cuscuta veatchii). Molecular phylogenetic studies confirmed the monophyly of this group and suggested that the disjunct C. veatchii is a hybrid between the other two species. However, the limited sampling left the possibility of alternative biological and methodological explanations. We expanded our sampling to multiple individuals of all the species collected from across their entire geographical ranges. Sequence data from the nuclear and plastid regions were used to reconstruct the phylogeny and find out if the topological conflict was maintained. We obtained karyotype information from multiple individuals, investigated the morphological variation of the group thorough morphometric analyses, and compiled data on ecology, host range, and geographical distribution. Our results confirmed that C. veatchii is an allotetraploid. Furthermore, we found previously unknown autotetraploid population of C. denticulata, and we describe a new hybrid species, Cuscuta psorothamnensis. We suggest that this newly discovered natural hybrid is resulting from an independent (and probably more recent) hybridization event between the same diploid parental species as those of C. veatchii. All the polyploids showed host shift associated with hybridization and/or polyploidy and are found growing on hosts that are rarely or never frequented by their diploid progenitors. The great potential of this group as a model to study host shift in parasitic plants associated with recurrent allopolyploidy is discussed.  相似文献   

17.
The species composition of Chironomus in the Curonian Lagoon has been investigated. It was shown that three sibling species of the plumosus group, namely, Ch. plumosus, Ch. balatonicus, and Ch. muratensis, and a first-generation interspecific hybrid Ch. muratensis × Ch. plumosus lived here. The occurrence frequency in the lagoon was 87, 19, 6, and 3% for Ch. plumosus, Ch. balatonicus, Ch. muratensis × Ch. plumosus, and Ch. muratensis, respectively. The species Ch. plumosus was recorded in all the areas (southern, central, and northern), while Ch. balatonicus was found only in the northern area in the village of Juodkrante near the city of Klaipeda. Presumably, the distribution of these sibling species is due to the presence of a salinity gradient in the lagoon.  相似文献   

18.
This study was focused on species of Peziza belonging to the “P. ammophila” complex, using both morphological and molecular approaches. Molecular and morphological analyses showed that several taxa are hidden under the name “ammophila” and, as a consequence, two additional species and one form are established: P. hellenica sp. nov., P. oceanica sp. nov. and P. ammophila f. megaspora f. nov. On the basis of the data that we have, these taxa seem to be related to some geographical areas; P. ammophila appears to be prevalent in northern, central and southern Europe, its f. megaspora is distributed in France and in the Netherlands, P. hellenica comes from Greece and P. oceanica from New Zealand. A cryptic species, not yet circumscribed satisfactorily, is described as P. deceptiva ad int. Moreover, the problem concerning the identification of P. ammophila is raised, the species is epitypified with a sequenced collection from Sicily (Italy) and a key to the species of the complex is provided.  相似文献   

19.
Although chondrichthyans are conspicuously present in shallow waters, many ecological aspects of neritic species in the Humboldt Current System remain unknown. This study provides a first assessment of the diet of seven commercially exploited and understudied sympatric chondrichthyans inhabiting nearshore habitats off the central coast of Peru: four stingrays (Hypanus dipterurus, Myliobatis peruvianus, M. chilensis, and Urotrygon chilensis), a guitarfish (Pseudobatos planiceps), a smooth-hound shark (Mustelus mento), and a chimaera (Callorhinchus callorynchus). A total of 166 stomachs were examined between 2012 and 2015 and prey items were pooled for the total of years for analysis. Although our analysis did not account for inter seasons variability, our results suggest diet partitioning among species, except for the stingrays’ group. A diet based on soft-bottom polychaetes and fish was shared by H. dipterurus, M. peruvianus, and M. chilensis, while soft-bottom polychaetes and crabs were more important in U. chilensis. The smooth-hound shark and guitarfish exhibited a diet dominated by crabs, and the chimaera consumed mainly hard-bottom mollusks. Foraging habitat estimations distinguished two main habitats of association: Benthic, including the stingray U. chilensis, the chimaera, and the smooth-hound shark; and benthic-demersal, including the guitarfish, and the rest of stingrays. A pattern of feeding specialization was observed for H. dipterurus, P. planiceps, and C. callorynchus. Preliminary trophic level estimations based on diet composition placed these species as secondary consumers. Intraspecific dietary variation was assessed for P. planiceps and H. dipterurus as their sampled sizes allowed meaningful comparisons. The diet of P. planiceps varied from small to large sizes but not for H. dipterurus. No differences were detected on diet composition between males and females in either species. Despite the limited temporal resolution, this study provides the first insights of chondrichthyans predatory activity, suggesting diet partitioning among the species of this assemblage in a nearshore habitat of the central coast of Peru. Enhancing the temporal resolution of this type of studies would improve our knowledge on trophic functioning in the Humboldt Current ecosystem.  相似文献   

20.
Тhe DNA testing of autosomal recessive deafness type 1A (DFNB1A, MIM 220290) is complicated when deaf patients have only monoallelic (heterozygous) recessive mutations in the GJB2 (Сх26) gene that is uninformative for establishment of diagnosis. Such patients may be “random” heterozygous carriers of GJB2 mutations as well as have the mutant allele in a cis-regulatory region of GJB2 gene, in element genes encoding other connexins: GJB6 (Сх30) or GJB3 (Сх31). Previous studies of genetic causes of hearing loss in patients from Yakutia were directed to search for only mutations in the GJB2 gene, and the DNA diagnostics was uninformative for 9.7% (38/393) of the patients with monoallelic GJB2 mutations. In this work the search for mutations in genes GJB3 and GJB6 and two deletions с.del(GJB6-D13S1830) and с.del(GJB6-D13S1854) to the cis-regulatory region of GJB2 gene was conducted in 35 patients with GJB2 monoallelic mutations and in 104 normal hearing individuals. The genes studied are two synonymous substitution c.489G>A (р.Leu163Leu) (GJB6) and c.357C>T (р.Asn119Asn) (GJB3) have been found, probably do not have clinical significance, and two nonsynonymous substitution c.301G>A (p.Glu101Lys) (GJB6) and с.580G>A (p.Ala194Thr) (GJB3). Additional experimental evidences are needed for confirmation of pathogenic significance of detected nonsynonymous substitutions in development of hearing loss in studied patients. Diagnosis of the DFNB1A was confirmed in only one patient, who was discovered by the deletion с.del(GJB6-D13S1830) (GJB2) in combination with a recessive mutation с.35delG (GJB2). In general, our results indicate low contribution of mutations in genes GJB6 and GJB3 in hearing loss etiology in Yakutia.  相似文献   

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