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Alexey A. Kotov - One of the best experts on this subject based on the ideXlab platform.
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Redescription of Daphnia turbinata Sars, 1903 (Crustacea: Cladocera: Daphniidae).
Zootaxa, 2019Co-Authors: Elena I. Zuykova, N. G. Sheveleva, Alexey A. KotovAbstract:The genus Daphnia O.F. Muller (Crustacea: Cladocera: Daphniidae) has a long history of its study, it attracts maximum attention of evolutionary biologists as compared to other cladoceran taxa. But still there are many unresolved problems concerning the genus taxonomy. We redescribe forgotten Daphnia (D.) turbinata Sars, 1903 which has a relatively narrow distribution in the Altay-Sayan mountain region (southern Siberia and Mongolia). Diagnostic characters of the taxon are discussed as well as possibilities of morphological discrimination of taxa within the D. (D.) longispina species group.
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Revision of the Old World Daphnia ( Ctenodaphnia ) similis group Cladocera: Daphniidae)
Zootaxa, 2016Co-Authors: Ekaterina V. Popova, Derek J Taylor, Adam Petrusek, Vladimír Kořínek, Joachim Mergeay, Eugeniya I. Bekker, D. P. Karabanov, Yan Galimov, Tatyana V. Neretina, Alexey A. KotovAbstract:Species of the genus Daphnia O.F. Muller, 1785 (Cladocera: Daphniidae) have become very important models in evolutionary biology research. Previous morphological and genetic evidence suggests that numerous closely related “species groups” exist within the subgenus Daphnia ( Ctenodaphnia ) Dybowski & Grochowski, 1895, containing both described and undescribed species. The Daphnia similis group is among these species groups. The aim of the present paper is to revise the taxonomy of the Daphnia ( Ctenodaphnia ) similis group in the Old World with both morphological and genetic evidence (based on mitochondrial COI and 12S rRNA genes). We found that there are at least four species in the Old World D. similis species group: D. similis Claus, 1876; D. sinensis Gu, Xu, Li, Dumont et Han, 2013; D. similoides Hudec, 1991 and D. inopinata sp. nov. These four taxa of the similis- group, confused previously with D. similis, have different distributional ranges in the Old World, from extremely wide, spanning several biogegraphic regions (as D. sinensis ), to regional endemics ( D. similoides ) and even species known so far from a single locality ( D. inopinata sp. nov.). The Daphnia similis group provides another example in the cladocerans whereby the study of males yields more valuable characters for taxonomy than the study of parthenogenetic females.
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daphnia lumholtzi sars 1885 cladocera Daphniidae invades argentina
Journal of Limnology, 2014Co-Authors: Alexey A. Kotov, Derek J TaylorAbstract:The extent of freshwater biological invasions is difficult to predict. The thermophilic Daphnia lumholtzi Sars, 1885 (Cladocera: Daphniidae) has successfully invaded a large section of temperate North America from an Old World source, damaging ecosystems and fisheries. The species was later reported introduced into Mexico and Brazil. Here we report D. lumholtzi in Argentina - the most southerly record in the New World for this species. Our genetic analyses establish haplotype identity with North American specimens, consistent with the colonization of South America from North America. The detection dates of the records in South America and the association with the Parana River, provide evidence that river ways play a role in expansion of D. lumholtzi. The invasion of D. lumholtzi has now reached a similar wide latitudinal span to the distribution in the Old World.
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Selectively maintained paleoviruses in Holarctic water fleas reveal an ancient origin for phleboviruses.
Virology, 2013Co-Authors: Matthew J. Ballinger, Alexey A. Kotov, Jeremy A. Bruenn, Derek J TaylorAbstract:The ecological model, Daphnia pulex (Cladocera: Daphniidae), is broadly distributed in Holarctic freshwater habitats and has been the subject of multidisciplinary study for over half a century, but never has a natural RNA virus infection been reported in daphnids. Here we report on a group of paleoviruses related to RNA dependent RNA polymerase in the genome of D. pulex. Phylogenetic analysis suggests that these paleoviruses are derived from a viral lineage within the genus Phlebovirus. Comparison of the genomic sequences flanking individual paleoviruses reveal that some are orthologous viral insertions having been present in the common ancestor of the D. pulex species complex, which is millions of years old. Still, we detected some sites that have the signature of purifying selection. In contrast, other paleoviruses in this group seem to be unique to specific host lineages and even contain undisrupted open reading frames, suggesting either more recent acquisition, or selective maintenance.
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molecular approach to identify sibling species of the ceriodaphnia cornuta complex cladocera Daphniidae from australia with notes on the continental endemism of this group
Zootaxa, 2013Co-Authors: Pranay Sharma, Alexey A. KotovAbstract:Taxonomy of the genus Ceriodaphnia Dana, 1853 (Cladocera: Daphniidae) has been uncertain for a long time, the species richness was often underestimated due to (1) a morphological similarity among the species and (2) their great morphological inter- and intra- populational variability. Support for this conclusion comes from the first analysis of three molecular markers for Australian representatives of this genus, two mitochondrial (COI and 16s) and one nuclear (28s) genes. Sequence analysis indicates the existence of three sibling Australian species belonging to the complex. Further work is required to establish species boundaries and investigate potential morphological diagnoses. Comparison of COI sequences with all other published sequences from the genus Ceriodaphnia revealed no common clades among continents pointing to the regional endemism within this group, which could suggest its Mesozoic differentiation.
N. M. Korovchinsky - One of the best experts on this subject based on the ideXlab platform.
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Cladocera (Crustacea, Branchiopoda) of Central Yakutia: 1. Some Representatives of the Families Sididae, Daphniidae, and Ophryoxidae
Biology Bulletin, 2017Co-Authors: A. I. Klimovsky, N. M. Korovchinsky, E. I. Bekker, A. A. KotovAbstract:This series of communications is aimed to report on a study of the water fleas (Crustacea, Cladocera) of Central Yakutia. This first communication provides brief descriptions of the representatives of the families Sididae, Daphniidae, and Ophryoxidae, namely Sida crystallina (O.F. Müller 1776), Diaphanosoma orghidani orghidani Negrea 1982, Diaphanosoma amurensis Korovchinsky et Sheveleva 2009, Diaphanosoma brachyurum (Liévin 1848), Scapholeberis mucronata (O.F. Müller 1776), Scapholeberis rammneri Dumont et Pensaert 1983, Megafenestra cf. nasuta (Birge 1879), Simocephalus cf. serrulatus (Koch 1841), and Ophryoxus kolymensis Smirnov 1992. Remarks are given on the occurrence of these taxa in Northern Eurasia.
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Cladocera (Crustacea, Branchiopoda) of Central Yakutia: 1. Some Representatives of the Families Sididae, Daphniidae, and Ophryoxidae
Biology Bulletin, 2017Co-Authors: A. I. Klimovsky, N. M. Korovchinsky, E. I. Bekker, A. A. KotovAbstract:This series of communications is aimed to report on a study of the water fleas (Crustacea, Cladocera) of Central Yakutia. This first communication provides brief descriptions of the representatives of the families Sididae, Daphniidae, and Ophryoxidae, namely Sida crystallina (O.F. Muller 1776), Diaphanosoma orghidani orghidani Negrea 1982, Diaphanosoma amurensis Korovchinsky et Sheveleva 2009, Diaphanosoma brachyurum (Lievin 1848), Scapholeberis mucronata (O.F. Muller 1776), Scapholeberis rammneri Dumont et Pensaert 1983, Megafenestra cf. nasuta (Birge 1879), Simocephalus cf. serrulatus (Koch 1841), and Ophryoxus kolymensis Smirnov 1992. Remarks are given on the occurrence of these taxa in Northern Eurasia.
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Species richness of pelagic Cladocera of large lakes in the eastern hemisphere
Hydrobiologia, 2000Co-Authors: N. M. KorovchinskyAbstract:The composition of the pelagic cladoceran species assemblages in some large, well-studied, lakes of Europe, Asia and Africa is reviewed based on original and literature data. In general, pelagic cladocerans are taxonomically less well studied than some littoral groups. Only the limnetic members of the family Sididae and some Daphnia have recently been revised, whereas knowledge of species diversity of other Daphniidae (including moinas) and Bosminidae is missing. Future detailed taxonomic studies may lead to considerable changes in understanding of limnetic zooplankton composition.
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THE CRUSTACEAN FAUNA (BRANCHIOPODA, COPEPODA) OF SHALLOW FRESHWATER BODIES IN ICELAND
2000Co-Authors: Olivier Scher, N. M. Korovchinsky, D. Defaye, Alain Thiéry, Victor Hugo, A. N. SevertsovAbstract:The Crustacean Fauna (Branchiopoda, Copepoda) of Shallow Freshwater Bodies in Iceland. Scher O., Defaye D., Korovchinsky N. M., Thiery A. – A survey of shallow freshwaters of Iceland was conducted in June and July 1996. The 34 stations prospected were rainpools, ditches, wetlands. The composition of their crustacean communities, investigated by qualitative net samples, is discussed in relation to water characteristics. One notostracan, Lepidurus arcticus (Pallas, 1793), 17 cladoceran species (5 Daphniidae, 10 Chydoridae, 1 Macrothricidae, 1 Polyphemidae), and 12 copepods (2 Diaptomidae, 7 Cyclopidae, 3 Canthocamptidae) were identified. Two species are reported for the first time from Iceland: the diaptomid Diaptomus (Chaetodiaptomus) rostripes Herbst, 1955 and the chydorid Alona rustica Scott, 1895. Taxonomical comments about different species are added, and their ecological pecularities are given. The species richness as well as the biogeographical features of the freshwater zooplankton of Iceland are discussed in relation to neighbouring Greenland and Northern Europe.
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How many species of Cladocera are there?
Hydrobiologia, 1996Co-Authors: N. M. KorovchinskyAbstract:An estimation of the number of taxa within families, genera and local faunas of Cladocera reveals that only c. 129 species (17% of all known species) may be considered as sufficiently well described (valid species), and c. 146 as rather well described (fair species) but needing further study using modern methods of investigation. The status of all other species is vague. The families Chydoridae, Daphniidae and Sididae and genera Diaphanosoma, Daphnia , (including Daphniopsis ), Megafenestra, Scapholeberis, Eurycercus, Chydorus, Ephemeroporus and Pleuroxus have been comparatively studied best. The largest number of valid species is known from Europe, North America, Australia and South America, and the smallest number from Africa. Presence of large number of vague species of Cladocera negatively affects faunistic, zoogeographic, and ecological studies of continental waters.
Marina Ja. Orlova-bienkowskaja - One of the best experts on this subject based on the ideXlab platform.
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A revision of the Simocephalus (latirostris) species group (Crustacea: Anomopoda: Daphniidae)
Hydrobiologia, 1995Co-Authors: Marina Ja. Orlova-bienkowskajaAbstract:The group of 3 species: Simocephalus latirostris, S. lusaticus and a new species, S. mesorostris , is given the rank of a subgenus. Descriptions and a key for the identification of these species are given. The unknown male of S. latirostris is described. The comparison of the lectotype of S. latitrostis with material from different regions shows that this species is not pantropical as previously supposed. It occurs only in South and Central America. S. mesorostris n. sp., living in Australia, the Malay Archipelago, South-East Asia and Africa, was previously confused with S. latirostris .
Derek J Taylor - One of the best experts on this subject based on the ideXlab platform.
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Revision of the Old World Daphnia ( Ctenodaphnia ) similis group Cladocera: Daphniidae)
Zootaxa, 2016Co-Authors: Ekaterina V. Popova, Derek J Taylor, Adam Petrusek, Vladimír Kořínek, Joachim Mergeay, Eugeniya I. Bekker, D. P. Karabanov, Yan Galimov, Tatyana V. Neretina, Alexey A. KotovAbstract:Species of the genus Daphnia O.F. Muller, 1785 (Cladocera: Daphniidae) have become very important models in evolutionary biology research. Previous morphological and genetic evidence suggests that numerous closely related “species groups” exist within the subgenus Daphnia ( Ctenodaphnia ) Dybowski & Grochowski, 1895, containing both described and undescribed species. The Daphnia similis group is among these species groups. The aim of the present paper is to revise the taxonomy of the Daphnia ( Ctenodaphnia ) similis group in the Old World with both morphological and genetic evidence (based on mitochondrial COI and 12S rRNA genes). We found that there are at least four species in the Old World D. similis species group: D. similis Claus, 1876; D. sinensis Gu, Xu, Li, Dumont et Han, 2013; D. similoides Hudec, 1991 and D. inopinata sp. nov. These four taxa of the similis- group, confused previously with D. similis, have different distributional ranges in the Old World, from extremely wide, spanning several biogegraphic regions (as D. sinensis ), to regional endemics ( D. similoides ) and even species known so far from a single locality ( D. inopinata sp. nov.). The Daphnia similis group provides another example in the cladocerans whereby the study of males yields more valuable characters for taxonomy than the study of parthenogenetic females.
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daphnia lumholtzi sars 1885 cladocera Daphniidae invades argentina
Journal of Limnology, 2014Co-Authors: Alexey A. Kotov, Derek J TaylorAbstract:The extent of freshwater biological invasions is difficult to predict. The thermophilic Daphnia lumholtzi Sars, 1885 (Cladocera: Daphniidae) has successfully invaded a large section of temperate North America from an Old World source, damaging ecosystems and fisheries. The species was later reported introduced into Mexico and Brazil. Here we report D. lumholtzi in Argentina - the most southerly record in the New World for this species. Our genetic analyses establish haplotype identity with North American specimens, consistent with the colonization of South America from North America. The detection dates of the records in South America and the association with the Parana River, provide evidence that river ways play a role in expansion of D. lumholtzi. The invasion of D. lumholtzi has now reached a similar wide latitudinal span to the distribution in the Old World.
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Selectively maintained paleoviruses in Holarctic water fleas reveal an ancient origin for phleboviruses.
Virology, 2013Co-Authors: Matthew J. Ballinger, Alexey A. Kotov, Jeremy A. Bruenn, Derek J TaylorAbstract:The ecological model, Daphnia pulex (Cladocera: Daphniidae), is broadly distributed in Holarctic freshwater habitats and has been the subject of multidisciplinary study for over half a century, but never has a natural RNA virus infection been reported in daphnids. Here we report on a group of paleoviruses related to RNA dependent RNA polymerase in the genome of D. pulex. Phylogenetic analysis suggests that these paleoviruses are derived from a viral lineage within the genus Phlebovirus. Comparison of the genomic sequences flanking individual paleoviruses reveal that some are orthologous viral insertions having been present in the common ancestor of the D. pulex species complex, which is millions of years old. Still, we detected some sites that have the signature of purifying selection. In contrast, other paleoviruses in this group seem to be unique to specific host lineages and even contain undisrupted open reading frames, suggesting either more recent acquisition, or selective maintenance.
Igor Hudec - One of the best experts on this subject based on the ideXlab platform.
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Redescription of Daphnia deserti (Gauthier, 1937) (Crustacea: Daphniiformes: Daphniidae)
Hydrobiologia, 1993Co-Authors: Igor HudecAbstract:Based on type material collected by Prof. H. Seurat the redescription of Daphnia (C.) deserti (Gauthier, 1937) is presented. Gautier (1929) determined this material as D. carinata cf. thomsoni and later (Gauthier, 1937) described as D. carinata ssp. deserti . The species belongs to a circummediterranean group of Ctenodaphniids ( D. chevreuxi, D. hispanica and D. dolichocephala ) with characteristic denticular arrangement on postabdomen. D. deserti is restricted to Sahara region.
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A comparison of populations from the Daphnia similis group (Cladocera: Daphniidae)
Biology of Cladocera, 1991Co-Authors: Igor HudecAbstract:European populations of Daphnia similis Claus have been compared with populations from tropical Asia. Daphnia similoides n. sp. from tropical Asia was described as the sibling species of D. similis. The female has characteristic neonate, postabdomen, head, and ephippium. The male has characteristic rostrum, antennules, and the distalmost part of the postabdomen. The D. similis group was compared with D. carinata s. str. Australian populations.
