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1.
The stratigraphic and paleogeographic ranges of Ordovician bryozoans of the genus Diplotrypa (Trepostomida: Halloporidae) are analyzed. It is shown that they were then limited in geographic range to the Paleobaltic Basin (the most probable center of origin of the genus Diplotrypa) and to the West Arctic and North American basins. The Silurian bryozoans of this genus were represented by only a few species. In addition, the intercolonial variability of the species Diplotrypa abnormis (Modzalevskaya, 1953) and D. petropolitana (Nicholson, 1879) is studied; Upper Ordovician specimens of these species have been discovered from the Leningrad Region of Russia for the first time. The colonies of these species from the Leningrad Region are compared here with those of Podolia (Western Ukraine) and Vaygach Island (western sector of the Russian Arctic).  相似文献   

2.
New brachiopods of the suborder Delthyridina Ivanova (order Spiriferida) from the Lower and Middle Devonian of northeastern Russia, Ivanothyris costatus sp. nov. (subfamily Delthyridinae), Eoreticularia lata sp. nov., Yania gen. nov. with the type species Y. tumida sp. nov. (subfamily Eoreticulariinae), Reticulariopsis equitans Modzalevskaya, and R. (?) borealis sp. nov. (subfamily Reticulariopsinae) are described.  相似文献   

3.
A new species of the subgenus Planempis Frey, 1953 (Diptera: Empididae), Empis (Planempis) gussakovskiisp. n., is described from Tajikistan, being the first record of the subgenus from Middle Asia. The relationships of the new species within the subgenus Planempis are shortly discussed. An updated check-list of Planempis species is provided.  相似文献   

4.
The mandibles in the first zoeal stage of five species of the burrowing shrimp genera Upogebia (infraorder Gebiidea) and Nihonotrypaea (infraorder Axiidea) have been examined by scanning electron microscopy. The general shape of the mandibles in Upogebia zoeae is similar to that in Anomura larvae; in Nihonotrypaea, it is intermediate between the mandibles of anomuran and caridean shrimp larvae. The asymmetry of the mandibles, which is more pronounced in Nihonotrypaea, is confirmed. Species-specific features of the structure of the incisor process are found in three Upogebia species, while two Nihonotrypaea species almost do not differ in the mandible structure in their zoea I larvae. The morphological features of the mandibles indicate differences in the diet of Upogebia and Nihonotrypaea larvae. Under natural conditions, zoea I of the studied Nihonotrypaea species may feed on diatoms, which should be taken into account when rearing these decapod larvae in the laboratory.  相似文献   

5.
The structure of the claspettes (modified projections in the male genitalia) in species of the subgenus Ochlerotatus Lynch Arribalzaga of the genus Aedes Meigen is described in detail. A thorough investigation of the three-dimensional structure of the claspettes is necessary for identification of the Ochlerotatus species from Russia. The study of 30 species of Ochlerotatus demonstrated that frequently the use of the claspette structure as a diagnostic character was incorrect when the claspettes were described as flat structures. Examination of the three-dimensional structure of the claspettes has revealed characters differentiating Aedes diantaeus, A. intrudens and A. pullatus; A. communis, A. punctor, and A. hexodontus; A. annulipes, A. excrucians, and A. euedes, as well as some other species.  相似文献   

6.
Invasive candidiasis is caused mainly by Candida albicans, but other Candida species have increasing etiologies. These species show different virulence and susceptibility levels to antifungal drugs. The aims of this study were to evaluate the usefulness of the non-conventional model Caenorhabditis elegans to assess the in vivo virulence of seven different Candida species and to compare the virulence in vivo with the in vitro production of proteinases and phospholipases, hemolytic activity and biofilm development capacity. One culture collection strain of each of seven Candida species (C. albicans, Candida dubliniensis, Candida glabrata, Candida krusei, Candida metapsilosis, Candida orthopsilosis and Candida parapsilosis) was studied. A double mutant C. elegans AU37 strain (glp-4;sek-1) was infected with Candida by ingestion, and the analysis of nematode survival was performed in liquid medium every 24 h until 120 h. Candida establishes a persistent lethal infection in the C. elegans intestinal tract. C. albicans and C. krusei were the most pathogenic species, whereas C. dubliniensis infection showed the lowest mortality. C. albicans was the only species with phospholipase activity, was the greatest producer of aspartyl proteinase and had a higher hemolytic activity. C. albicans and C. krusei caused higher mortality than the rest of the Candida species studied in the C. elegans model of candidiasis.  相似文献   

7.
A complex of the heteropteran genera centering around Peribalus Mulsant et Rey and Holcostethus Fieber is considered. The genus Dryadocoris Kirkaldy reveals no relationship with the above genera and is believed to represent a separate clade of the family Pentatomidae. The genera Peribalus and Holcostethus are revised. The former includes three subgenera: Peribalus s. str. with two species, Asioperibalus subgen. n. (type species Cimex inclusus Dohrn) with six species, and Tianocoris subgen. n. (type species Holcostethus manifestus Kiritshenko) with two species. Holcostethus embraces two subgenera: Holcostethus s. str. and the monotypic Enigmocoris subgen. n. (type species H. fissiceps Horváth). Two new species are described: Peribalus tianshanicus sp. n. from the Tien Shan Mts. and P. przewalskii sp. n. from the northern part of China (Huan He River). P. capitatus Jakovlev and P. vernalis (Wolff) are downgraded to subspecies of P. strictus (F.). P. ovatus Jakovlev is synonymized with P. inclusus (Dohrn). Two new monotypic genera related to the revised complex of genera are established, Paraholcostethus gen. n. (type species Peribalus breviceps Horváth) and Himalayastethus gen. n. (type species H. pilosus sp. n. from Kashmir). A key to, and morphometric characters for all the taxa considered are provided. The key characters, including both male and female genitalia, are illustrated, and distributional maps are given.  相似文献   

8.
Larvae of three Nymphon species are described. For Nymphon brevirostre Hodge, 1863 and Nymphon micronyx Sars, 1888 protonymphon larvae are examined, larvae of N. micronyx have been studied for the first time. The fine external morphology of larvae is studied in detail using SEM methods; the internal structure of N. brevirostre protonymphon is additionally described. SEM data on external morphology and fine surface structures are given for several postembryonic stages of Nymphon grossipes Fabricius, 1780. Different types of postembryonic development are revealed in examined Nymphon species. N. brevirostre and N. micronyx have a “typical protonymphon” developmental pathway. A special developmental pathway named “lecithotrophic protonymphon” is suggested for N. grossipes and other Nymphonidae having large yolky eggs.  相似文献   

9.
Based on the male genitalia structure, 3 subgenera are distinguished in the genus Thamnurgus: Thamnurgus s. str. (type species Thamnurgus euphorbiae Küster; the subgenus includes also Th. characiae and Th. varipes), Parathamnurgus subgen. n. (type species Thamnurgus caucasicus Reitter; includes also Th. armeniacus, Th. kaltenbachii, Th. brylinskyi, and Th. pegani) and Macrothamnurgus subgen. n. (type species Thamnurgus delphinii Rosenhauer; includes also Th. petzi and Th. rossicus). Thamnurgus s. str. comprises species with the aedeagus lacking supporting apical structures and with unbranched apophyses. In the two other subgenera the aedeagal apophyses are branched and the apical supporting structures are differently arranged. Species of Thamnurgus s. str. are associated exclusively with Euphorbiaceae, species of Macrothamnurgus, with Ranunculaceae, and those of Parathamnurgus, with plants of several families. A key to Palaearctic Thamnurgus species based on the external and genital characters is proposed. The host plants and distribution of some species are clarified. In the aedeagus structure, the Palaearctic Thamnurgus species clearly differ from the African Thamnurgus and also from the members of Taphronurgus, Cynanchophagus, Triotemnus, and Xylocleptes. Data on the male genital structure support generic distinctness of Thamnurgus, Taphronurgus and Xylocleptes. Lectotypes of Th. armeniacus Reitter, 1897, Th. brylinskyi Reitter, 1889, Th. characiae Rosenhauer, 1878, Th. declivis Reitter, 1897, Th. delphinii (Rosenhauer, 1856), Th. pegani Eggers, 1933, and Th. petzi Reitter, 1901 are designated. Thamnurgus jemeniae Schedl, 1975 is transferred to Xylocleptes, and Th. orientalis Schedl, 1978, to Pseudothamnurgus. Based on the endophallus characters, Thamnurgus ugandensis Nunberg, 1961 and Th. lobeliae Eggers, 1939 are considered to belong to a genus distinct from the Palaearctic Thamnurgus.  相似文献   

10.
Coffea arabica (the Arabica coffee) is an allotetraploid species originating from a recent hybridization between two diploid species: C. canephora and C. eugenioides. Transposable elements can drive structural and functional variation during the process of hybridization and allopolyploid formation in plants. To learn more about the evolution of the C. arabica genome, we characterized and studied a new Copia LTR-Retrotransposon (LTR-RT) family in diploid and allotetraploid Coffea genomes called Divo. It is a complete and relatively compact LTR-RT element (~5 kb), carrying typical Gag and Pol Copia type domains. Reverse Trancriptase (RT) domain-based phylogeny demonstrated that Divo is a new and well-supported family in the Bianca lineage, but strictly restricted to dicotyledonous species. In C. canephora, Divo is expressed and showed a genomic distribution along gene rich and gene poor regions. The copy number, the molecular estimation of insertion time and the analysis at orthologous locations of insertions in diploid and allotetraploid coffee genomes suggest that Divo underwent a different and recent transposition activity in C. arabica and C. canephora when compared to C. eugenioides. The analysis of this novel LTR-RT family represents an important step toward uncovering the genome structure and evolution of C. arabica allotetraploid genome.  相似文献   

11.
The genetic diversity and population structure of the endemic species of Baikal Siberia Oxytropis triphylla, O. bargusinensis, and O. interposita were studied for the first time on the basis of the nucleotide polymorphism of intergenic spacers psbA–trnH, trnL–trnF, and trnS–trnG of chloroplast DNA. All populations of these species were characterized by a high haplotype (0.762–0.924) and relatively low nucleotide (0.0011–0.0022) diversity. Analysis of the distribution of variability in O. triphylla and O. bargusinensis showed that there was no significant genetic differentiation between populations of each species; the gene flow was 4.43 and 8.91, respectively. The high level of genetic diversity in the studied populations indicates a relatively stable state of these populations. A study of the phylogenetic relationships of closely related species confirms the concept of the origin of O. bargusinensis and O. tompudae as a result of intersectional hybridization of the species of the sections Orobia and Verticillares.  相似文献   

12.
The aporocotylid fauna of the mottled spinefoot, Siganus fuscescens (Houttuyn), from Moreton Bay, Queensland, Australia, was characterised using a combined morphological and molecular approach. Four aporocotylid species were identified, three belonging to the genus Ankistromeces Nolan & Cribb, 2006 and one to Cardicola Short, 1953. Specimens of Cardicola matched an undescribed species from the same host and locality; this species is described as Cardicola mogilae n. sp. Phylogenetic analyses of ITS2 and 28S data showed that C. mogilae n. sp. forms a strongly supported clade with other Cardicola species from siganid fishes. We record Ankistromeces olsoni Nolan & Cribb, 2006 in Moreton Bay for the first time, redescribe A. dunwichensis Nolan & Cribb, 2006 on the basis of new specimens and sequence data and re-report Ankistromeces sp. X from Moreton Bay based on molecular data. We review the status of the ten putative species of aporocotylids reported from siganids. Small variation in ITS2 rDNA sequences, in association with different geographic localities, was previously used to separate Cardicola lafii Nolan & Cribb, 2006 from C. parilus Nolan & Cribb, 2006, C. bartolii Nolan & Cribb, 2006 from C. watsonensis Nolan & Cribb, 2006, C. tantabiddii Nolan & Cribb, 2006 from Cardicola sp. 2, Ankistromeces sp. Y from A. olsoni and Ankistromeces sp. X from Ankistromeces sp. Z. These five combinations are reinterpreted as each representing a single species; Cardicola lafii is recognised as the senior synonym of C. parilus and C. bartolii as the senior synonym of C. watsonensis. This study thus suggests that six, rather than ten, species should be recognised as infecting S. fuscescens. This richness remains greater than is known for any other fish species and siganids are, so far, unique among fishes in harbouring two strongly radiated lineages of aporocotylids.  相似文献   

13.
14.
The structure of the abdominal and pregenital segments and genitalia of males was studied in Pyrellia rapax (Harris, 1780) and Musca autumnalis De Geer, 1776 (Muscidae, Muscini). The musculature of these species is compared with that in Musca domestica Linnaeus, 1758 (Muscidae) and Scathophaga stercoraria (Linnaeus, 1758) (Scathophagidae), previously investigated by O.G. Ovtshinnikova. Morphological analysis of sclerites and muscles of abdominal and pregenital segments and genitalia of males in Pyrellia rapax, Musca autumnalis, and M. domestica demonstrates processes of reduction in Musca as compared with P. rapax and S. stercoraria.  相似文献   

15.
The sorbitol-6-phosphate dehydrogenase gene (S6PDH) sequences of eight tribe Pyreae species (Rosaceae) are studied for the first time. The exon–intron structure and polymorphism of the nucleotide and amino acid sequences of this gene are characterized. The interspecific polymorphism of the S6PDH coding sequences in the studied Pyreae species is 8.36%. Sorbitol-6-phosphate dehydrogenase gene expression in S. aucuparia, A. melanocarpa, and M. domestica (cv. Skala) leaves is studied. The highest level of S6PDH expression is detected in mature leaves.  相似文献   

16.
Hybridization is regarded as a rapid mechanism for increasing genetic variation that can potentially enhance invasiveness. Tamarix hybrids appear to be the dominant genotypes in their invasions. Exotic Tamarix are declared invasive in South Africa and the exotic T. chinensis and T. ramosissima are known to hybridize between themselves, and with the indigenous T. usneoides. However, until now, it was not known which species or hybrid is the most prevalent in the invasion. With a biocontrol programme being considered as a way of suppressing the alien Tamarix populations, it is important to document the population genetic dynamics of all species in the region. This investigation sought to identify Tamarix species in southern Africa and their hybrids, describe their population structure, and reveal the geographic origin of the invasive species. To achieve this, nuclear Internal Transcribed Spacer (ITS) sequence data and the multilocus Amplified Fragment Length Polymorphisms (AFLPs) markers were used. Phylogenetic analysis and population genetic structure confirmed the presence of three species in South Africa (T. chinensis, T. ramosissima and T. usneoides) with their hybrids. The indigenous T. usneoides is clearly genetically distant from the alien species T. chinensis and T. ramosissima. Interestingly, the Tamarix infestation in South Africa is dominated (64.7 %) by hybrids between T. chinensis and T. ramosissima. The exotic species match their counterparts from their places of origin in Eurasia, as well as those forming part of the invasion in the US.  相似文献   

17.
Karyotypic features as well as larval and imaginal morphology have been studied in five species of the black fly genus Wilhelmia, viz. W. equina (Linnaeus, 1758), W. pseudequina (Seguy, 1921), W. lineata (Meigen, 1804), W. veltistshevi (Rubzov, 1940), and W. salopiensis (Edwards, 1927). Photomaps of polytene chromosomes are given for all species (those for W. pseudequina and W. veltistshevi, for the first time). Species-specific karyological and morphological characters have been revealed. According to principal karyological features, the species examined are divided into the equina and salopiensis groups. The validity of the species rank is confirmed for all species. Clear karyological and morphological distinctions between W. salopiensis and W. lineata give evidence that synonymization of W. salopiensis with W. lineata was erroneous.  相似文献   

18.
Pachyphlodes (Pezizaceae) is a genus of truffle-like fungi that is distributed across the Northern Hemisphere. These fungi form ectomycorrhizae primarily with trees in the Fagaceae family, and occasionally with other host plants. The genus Plicariella (= Scabropezia) is phylogenetically inferred as an ally of, or within, the Pachyphlodes lineage. Despite molecular phylogenetic analyses that show the close relationships of species in these two genera, morphological differences in ascomata shape and color, spore ornamentation, and ascus shape are profound. Here, we studied spore wall development to better understand affinities within the PachyphlodesPlicariella lineages. Electron microscopy studies indicate that the initial spore wall development is similar across six Pachyphlodes species and a Plicariella species, despite striking differences in mature spore ornamentation among species. Ultrastructural analyses reveal that differences in spore ornamentation among Pachyphlodes species are due to unique developmental events at the final stages of spore wall deposition. Septal pore ultrastructure in Pachyphlodes species is similar to other Pezizaceae that have been studied. Molecular analyses of the five species studied indicate that four of them have not been previously described. The new species Pachyphlodes annagardnerae is here described, and the ultrastructural features of species of Pachyphlodes, Plicariella, and other Pezizales are compared and discussed.  相似文献   

19.
Prunus yedoensis Matsumura is one of the popular ornamental flowering cherry trees native to northeastern Asia, and its wild populations have only been found on Jeju Island, Korea. Previous studies suggested that wild P. yedoensis (P. yedoensis var. nudiflora) is a hybrid species; however, there is no solid evidence on its exact parental origin and genomic organization. In this study, we developed a total of 38 nuclear gene-based DNA markers that can be universally amplifiable in the Prunus species using 586 Prunus Conserved Orthologous Gene Set (Prunus COS). Using the Prunus COS markers, we investigated the genetic structure of wild P. yedoensis populations and evaluated the putative parental species of wild P. yedoensis. Population structure and phylogenetic analysis of 73 wild P. yedoensis accessions and 54 accessions of other Prunus species revealed that the wild P. yedoensis on Jeju Island is a natural homoploid hybrid. Sequence-level comparison of Prunus COS markers between species suggested that wild P. yedoensis might originate from a cross between maternal P. pendula f. ascendens and paternal P. jamasakura. Moreover, approximately 81% of the wild P. yedoensis accessions examined were likely F1 hybrids, whereas the remaining 19% were backcross hybrids resulting from additional asymmetric introgression of parental genotypes. These findings suggest that complex hybridization of the Prunus species on Jeju Island can produce a range of variable hybrid offspring. Overall, this study makes a significant contribution to address issues of the origin, nomenclature, and genetic relationship of ornamental P. yedoensis.  相似文献   

20.
Aluminum (Al) is the main limiting factor for crop production in acidic soils. Efflux of organic acids is one of the mechanisms that determine Al-tolerance, and an Al-activated citrate transporter (multidrug and toxic compound extrusion) MATE1 gene is involved in different species. The contribution of the rye MATE1 gene (ScMATE1) depends on the rye (Secale cereale L.) cultivars and the crosses analyzed; there is no information about different rye species. The cDNA sequences, phylogenetic relationships, Al-tolerance, citrate exudation, and expression of the ScMATE1 gene were analyzed in several cultivars and wild species/subspecies of the Secale genus. Genotypes highly tolerant to Al were found within this genus. For the first time, sequences of the cDNA of the ScMATE1 gene were isolated and characterized in wild ryes. At least two copies of this gene were found likely to be related to Al-tolerance. The sequence comparison of 13 exons of ScMATE1 revealed variability between species, but also inter- and intra-cultivars. Variations were found in the Al-induced expression of ScMATE1 gene, as well as its contribution to Al-tolerance. The pattern of citrate exudation was inducible in most of the species/subspecies studied and constitutive in few. The phylogenetic analysis indicated that ScMATE1 is orthologue of two genes (HvMATE1 and TaMATE1) involved in the Al stress response in barley and wheat, respectively, but not orthologue of SbMATE, implicated in Al-tolerance in sorghum. ScMATE1 is involved in the response to Al stress in ryes, but its contribution to Al-tolerance is complex, and like in other species, there are tolerant and sensitive alleles in the different cultivars and species studied.  相似文献   

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