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1.
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   

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Alaimella cincta Cobb 1920 and Alaimella macramphis sp. n. are described and illustrated. Both the species were first recorded for the White Sea in northern Russia. A. cincta occurs in the shells of the agglutinated foraminiferan Reophax curtus, as well as freely in bottom sediments. A. macramphis sp. n. is described from a single male sampled from bottom sediments. A. macramphis sp. n. is distinguished from two previously known species of Alaimella (A. cincta Cobb 1920 and A. truncate Cobb 1920) by having a longer body, longer cephalic setae, and a wide amphid equal to the respective body diameter. The new species also differs from A. truncate by the distinct striation of the cuticular annulations. The Alaimella species are additionally characterized by having a posterior glandular widening of the esophagus. An emended diagnosis of the genus Alaimella Cobb 1920 and a key for species identification are provided.  相似文献   

4.
The genus Eckhardites Mitta 1999, with the type species Macrocephalites pavlowi Smorodina, 1928 is discussed and its diagnosis and assignment to the family Cardioceratidae are substantiated. Eckhardites is compared to the genus Macrocephalites Zittel (family Sphaeroceratidae), to which some workers presently assign the type species of Eckhardites. Three species of Eckhardites are recorded from the basal Callovian elatmae Zone of the Russian Platform, one of which (E. menzeli (Mönnig)) was originally described from the synchronous beds in Germany. A new species E. dietli sp. nov. is described.  相似文献   

5.
The molecular karyotyping analysis of 21 strains within the taxonomic complex Pichia membranifaciens allowed the sibling species P. membranifaciens and P. manshurica, as well as P. deserticola and P. punctispora, to be differentiated. Heterogeneity of the species P. membranifaciens at the variety level is discussed.  相似文献   

6.
Across Western Europe and North America, many bumblebee species are currently undergoing drastic declines in their abundance and ranges, primarily as a result of habitat fragmentation. In contrast, a smaller number of species are seemingly unaffected by this and remain common. The UK Biodiversity Action Plan-designated Bombus ruderatus belongs to the former group while B. hortorum belongs to the latter. These two species are sympatric and remarkably similar in morphology. There are no diagnostic characters for workers and male genitalia are illustrated with the same diagram in standard keys. Isolated records of putative B. ruderatus occur amongst a mass of records for B. hortorum. This raises two important issues: first, are B. ruderatus and B. hortorum ‘good’ species? Second, if they are, can the uncertainty over their identification be resolved? We present COII and cytochrome b mtDNA sequence data from these and other Bombus species. Molecular data and coat colour characters are in concordance and confirm that B. ruderatus and B. hortorum should be regarded as separate species (although coat colour alone is an unreliable diagnostic character for many individuals). Confirmation of the specific status of B. ruderatus allows the work on the conservation of this species to continue.  相似文献   

7.
Interactions among the unattached red alga Gracilaria gracilis, the dominant species of an algal community, and associated algal species Chaetomorpha linum, Enteromorpha prolifera f. prolifera, and Polysiphonia sp. were studied during and after an algal bloom. It was shown that during their bloom the associated algae Enteromorpha and Polysiphonia sp. significantly decreased the photosynthetic rate of G. gracilis but did not affect its growth rate. It is suggested that the inhibition of Gracilaria gracilis photosynthesis is connected to the impact of extracellular metabolites excreted by Chaetomorpha linum, Enteromorpha prolifera f. prolifera, and Polysiphonia sp. In laboratory experiments, the photosynthetic rate of the associated species was enhanced in the presence of Gracilaria. However, no significant alterations were observed in the content of chlorophyll a, growth, and the dark respiration rates of associated algae when they were kept together with Gracilaria. It was suggested that allelopathic interactions observed among algal species during the formation of the monospecific Gracilaria community, as well as during algal blooms, are not determinative.  相似文献   

8.
Distribution of the Devonian conodont genus Pelekysgnathus is considered. A new species, P. jeppssoni sp. nov. from the Mosolovian Regional Stage (Middle Devonian, Eifelian) of the Voronezh Anteclise is described.  相似文献   

9.
The genus Tournayellina (family Chernyshinellidae), important for stratigraphy of the Devonian–Carboniferous boundary interval, is revised. Species and generic morphological characters are considered and the species composition of the genus is revised. The evolution of the family is discussed and its geographical and stratigraphic distribution is examined. The species Tournayellina quadrilobata Postojalko, 1999 is redescribed in accordance with new data on its morphology. The new species T. intermedia Stepanova, sp. nov. is established.  相似文献   

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A new spiriferid genus Paraimbrexia with the type species Imbrexia topkensis Besnossova, 1959 is established within the family Imbrexiidae Carter, 1992 from the Abyshevo Horizon, Famennian, Upper Devonian of the Kuznetsk Basin. Revision of the type material of I. topkensis revealed that this species strongly differs from the other species of Imbrexia Nalivkin, 1937 in details of shell exterior and interior.  相似文献   

12.
New concepts of systematics and phylogeny of the Permian Inoceramus-like bivalve mollusks of the eastern part of the Boreal zone are discussed based on analysis of the group’s historical development. All taxa studied are referred to the family Kolymiidae Kusnezov, which is divided into two subfamilies, Kolymiinae and Atomodesmatinae. In the subfamily Kolymiinae, two new genera are described: Praekolymia with the type species P. archboldi sp. nov. and P. urbajtisae sp. nov., and Taimyrokolymia with the type species T. ustritskyi sp. nov. In the subfamily Atomodesmatinae, two new genera, Costatoaphanaia and Okhotodesma, are described. The development of the group is shown to be generally autochthonous with some invasions (genus Atomodesma and, probably, Trabeculatia) from extraboreal regions.  相似文献   

13.
The genus Riasanites, represented in Central Russia by two successive dimorphic species, is revised. R. swistowianus is found in the basal beds of the rjasanensis Zone. Its descendant R. rjasanensis is also found in this zone, but upwards in the section, including the beds with Surites spasskensis and Externiceras solowaticum. The representatives of Riasanites from the Crimea and Northern Caucasus are assigned to two species, R. crassicostatus and R. maikopensis, respectively. It is suggested that Riasanites evolved from Sub-Mediterranean Himalayatidae, which migrated from the Western Tethys via the Polish Passage into the Central Russian Basin, and from there to Mangyshlak, the Northern Caucasus, and the Crimea.  相似文献   

14.
Chloroplast rpS16 gene intron sequences were determined and characterized for twenty-five Lemnaceae accessions representing nine duckweed species. For each Lemnaceae species nucleotide substitutions and for Lemna minor, Lemna aequinoctialis, Wolffia arrhiza different indels were detected. Most of indels were found for Wolffia arrhiza and Lemna aequinoctialis. The analyses of intraspecific polymorphism resulted in identification of several gaplotypes in Lemna gibba and Lemna trisulca. Lemnaceae phylogenetic relationship based on rpS16 intron variability data has revealed significant differences between Lemna aequinoctialis and other Lemna species. Genetic distance values corroborated competence of Landoltia punctata separations from Spirodela into an independent generic taxon. The acceptability of rpS16 intron sequences for phylogenetic studies in Lemnaceae was shown.  相似文献   

15.
Three new species of Davilla (Davilla sessilifolia, Davilla minutifolia and Davilla aymardii) from Bahia, Brazil, are described and illustrated. Affinities and diagnostic characteristics of each species are discussed. The new species belong to Davilla sect. Homalochlaena.  相似文献   

16.
A new conodont species, Polygnathus postvogesi sp. nov., from the Tournaisian deepwater deposits of the northern Urals, southeastern part of the Chernyshev Ridge, and central Pai-Khoi is described. The new species continue the phylogenetic lineage of the Late Devonian polygnathid P. marginvolutus Gedik, P. vogesi Ziegler.  相似文献   

17.
A new pycnosteid species, Schizosteus shkurlatensis sp. nov. (Agnatha, Psammosteiformes), from the Staryi Oskol beds (Givetian, Middle Devonian) of the Voronezh Region is described. This is the first species of the genus Schizosteus Obruchev from the Central Devonian Field. The similarity between species of this genus and early species of Psammolepis is discussed.  相似文献   

18.
The composition and distribution of the species of the genus Scalaspira Conrad, 1862 in the Eocene-Oligocene of western Kazakhstan are revised. Following Tembrock we assign this genus to Buccinidae and synonymize Aquilofusus Kautsky, 1925 with it. The stratigraphic interval studied contains at least eight species. Three species are new: S. alexeevi (Middle? and Upper Eocene, Chegan Formation), S. korobkovi, and S. kumsuatensis (Upper Oligocene, Karatomak Beds).  相似文献   

19.
Middle Devonian conodonts from the Si Phai section in NE Vietnam are described. The section ranges from the Middle Devonian ensensis to timorensis conodont zones to the Late Devonian rhomboidea conodont Zone. A rich overall assemblage is described, including 27 taxa of species or subspecies rank and 11 taxa described in an open nomenclature. Among the dominant Polygnathus forms, four new taxa are described: Polygnathus linguiformis saharicus subsp. nov., Polygnathus linguiformis vietnamicus subsp. nov., Polygnathus rhenanus siphai subsp. nov., and Polygnathus xylus bacbo subsp. nov. Conodont assemblages are attributed to polygnathid, polygnathid-klapperinid, and klapperinid conodont biofacies representing hemipelagic to pelagic environments. The klapperinid biofacies, unreported in the previous literature, are here attributed to offshore areas of the external shelf. The taxonomic compositions of the studied conodont assemblages, as well as their CAI characteristics (CAI 4–5), suggest a palaeogeographic affinity of the studied strata to the Chinese Devonian Guangxi Basin, and the South China Terrane in general. Furthermore, the conodont biofacies and the palaeogeographic distribution of the fauna are discussed.  相似文献   

20.
The yeasts of the Malassezia genus are opportunistic microorganisms and can cause human and animal infections. They are commonly isolated from the skin and auricular canal of mammalians, mainly dogs and cats. The present study was aimed to isolate Malassezia spp. from the acoustic meatus of bats (Molossus molossus) in the Montenegro region, “Rondônia”, Brazil. From a total of 30 bats studied Malassezia spp. were isolated in 24 (80%) animals, the breakdown by species being as follows (one Malassezia sp. per bat, N = 24): 15 (62.5%) M. pachydermatis, 5 (20.8%) M. furfur, 3 (12.5%) M. globosa and 1 (4.2%) M. sympodialis. This study establishes a new host and anatomic place for Malassezia spp., as it presents the first report ever of the isolation of this genus of yeasts in the acoustic meatus of bats.  相似文献   

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