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Jakub Těšitel - One of the best experts on this subject based on the ideXlab platform.
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molecular and morphological patterns across Acanthocyclops vernalis robustus species complex copepoda cyclopoida
Zoologica Scripta, 2010Co-Authors: Martin Bláha, Martin Hulák, Jana Slouková, Jakub TěšitelAbstract:Blaha, M., Hulak, M., Sloukova, J. & Těsitel, J. (2010). Molecular and morphological patterns across Acanthocyclops vernalis-robustus species complex (Copepoda, Cyclopoida).—Zoologica Scripta, 39, 259–268. Morphological traits within Acanthocyclops (Kiefer, 1927) are highly variable, and morphology is too constrained to give complete information of phylogenetic relationships. This study combined morphological and molecular techniques to investigate the taxonomic and phylogenetic relationships of three species of Acanthocyclops (Acanthocyclops trajani, Acanthocyclops einslei and Acanthocyclops vernalis) inhabiting continental Europe. Morphological indices subjected to principal component analysis (PCA) separated sample populations into three distinct clusters corresponding with the taxonomic status of the species analysed. In addition, the taxonomy status of A. trajani and A. einslei was in agreement with molecular data; however, the intraspecific variation in sequences of 12S rRNA was lower in contrast to specimens morphologically determined as A. vernalis, which were divided into two deeply divergent clades, based on mtDNA sequence divergences. Moreover, high sequence divergence (26%) between these clades indicated the existence of another species that may not be a sister taxon of A. vernalis s.s. Results point to the need for further taxonomic work on Acanthocyclops.
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Molecular and morphological patterns across Acanthocyclops vernalis‐robustus species complex (Copepoda, Cyclopoida)
Zoologica Scripta, 2010Co-Authors: Martin Bláha, Martin Hulák, Jana Slouková, Jakub TěšitelAbstract:Blaha, M., Hulak, M., Sloukova, J. & Těsitel, J. (2010). Molecular and morphological patterns across Acanthocyclops vernalis-robustus species complex (Copepoda, Cyclopoida).—Zoologica Scripta, 39, 259–268. Morphological traits within Acanthocyclops (Kiefer, 1927) are highly variable, and morphology is too constrained to give complete information of phylogenetic relationships. This study combined morphological and molecular techniques to investigate the taxonomic and phylogenetic relationships of three species of Acanthocyclops (Acanthocyclops trajani, Acanthocyclops einslei and Acanthocyclops vernalis) inhabiting continental Europe. Morphological indices subjected to principal component analysis (PCA) separated sample populations into three distinct clusters corresponding with the taxonomic status of the species analysed. In addition, the taxonomy status of A. trajani and A. einslei was in agreement with molecular data; however, the intraspecific variation in sequences of 12S rRNA was lower in contrast to specimens morphologically determined as A. vernalis, which were divided into two deeply divergent clades, based on mtDNA sequence divergences. Moreover, high sequence divergence (26%) between these clades indicated the existence of another species that may not be a sister taxon of A. vernalis s.s. Results point to the need for further taxonomic work on Acanthocyclops.
Martin Bláha - One of the best experts on this subject based on the ideXlab platform.
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descriptions of copepodid and adult Acanthocyclops trajani mirabdullayev defaye 2002 and a einslei mirabdullayev defaye 2004 copepoda cyclopoida with notes on their discrimination
Fundamental and Applied Limnology, 2010Co-Authors: Martin BláhaAbstract:The copepodid phases and adults of Acanthocyclops trajani and Acanthocyclops einslei were studied to record their distinguishing characteristics. Morphological examination showed that copepodids of both species were very similar, and showed an identical pattern of articulation and ornamentation of appendages and antennules. Differences in the distal endopodid of the fourth swimming leg and antennal ornamentation were found in later stage copepodids of both species. A. trajani had a higher ratio of apical spines on the distal endopodid of the fourth swimming leg compared to A. einslei, as well as a higher segment length/width ratio, and site of lateral spine insertion, which is more distal in A. einslei compare to A. trajani. Based on morphological descriptions of the copepodids of A. trajani and A. einslei, reported in this study, discrimination of later stage copepodids is feasible and may serve as a tool for basic ecological studies of zooplankton communities that is not dependent on the presence of adult specimens.
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Descriptions of copepodid and adult Acanthocyclops trajani (Mirabdullayev & Defaye 2002) and A. einslei (Mirabdullayev & Defaye 2004) (Copepoda: Cyclopoida) with notes on their discrimination
Fundamental and Applied Limnology, 2010Co-Authors: Martin BláhaAbstract:The copepodid phases and adults of Acanthocyclops trajani and Acanthocyclops einslei were studied to record their distinguishing characteristics. Morphological examination showed that copepodids of both species were very similar, and showed an identical pattern of articulation and ornamentation of appendages and antennules. Differences in the distal endopodid of the fourth swimming leg and antennal ornamentation were found in later stage copepodids of both species. A. trajani had a higher ratio of apical spines on the distal endopodid of the fourth swimming leg compared to A. einslei, as well as a higher segment length/width ratio, and site of lateral spine insertion, which is more distal in A. einslei compare to A. trajani. Based on morphological descriptions of the copepodids of A. trajani and A. einslei, reported in this study, discrimination of later stage copepodids is feasible and may serve as a tool for basic ecological studies of zooplankton communities that is not dependent on the presence of adult specimens.
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molecular and morphological patterns across Acanthocyclops vernalis robustus species complex copepoda cyclopoida
Zoologica Scripta, 2010Co-Authors: Martin Bláha, Martin Hulák, Jana Slouková, Jakub TěšitelAbstract:Blaha, M., Hulak, M., Sloukova, J. & Těsitel, J. (2010). Molecular and morphological patterns across Acanthocyclops vernalis-robustus species complex (Copepoda, Cyclopoida).—Zoologica Scripta, 39, 259–268. Morphological traits within Acanthocyclops (Kiefer, 1927) are highly variable, and morphology is too constrained to give complete information of phylogenetic relationships. This study combined morphological and molecular techniques to investigate the taxonomic and phylogenetic relationships of three species of Acanthocyclops (Acanthocyclops trajani, Acanthocyclops einslei and Acanthocyclops vernalis) inhabiting continental Europe. Morphological indices subjected to principal component analysis (PCA) separated sample populations into three distinct clusters corresponding with the taxonomic status of the species analysed. In addition, the taxonomy status of A. trajani and A. einslei was in agreement with molecular data; however, the intraspecific variation in sequences of 12S rRNA was lower in contrast to specimens morphologically determined as A. vernalis, which were divided into two deeply divergent clades, based on mtDNA sequence divergences. Moreover, high sequence divergence (26%) between these clades indicated the existence of another species that may not be a sister taxon of A. vernalis s.s. Results point to the need for further taxonomic work on Acanthocyclops.
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Molecular and morphological patterns across Acanthocyclops vernalis‐robustus species complex (Copepoda, Cyclopoida)
Zoologica Scripta, 2010Co-Authors: Martin Bláha, Martin Hulák, Jana Slouková, Jakub TěšitelAbstract:Blaha, M., Hulak, M., Sloukova, J. & Těsitel, J. (2010). Molecular and morphological patterns across Acanthocyclops vernalis-robustus species complex (Copepoda, Cyclopoida).—Zoologica Scripta, 39, 259–268. Morphological traits within Acanthocyclops (Kiefer, 1927) are highly variable, and morphology is too constrained to give complete information of phylogenetic relationships. This study combined morphological and molecular techniques to investigate the taxonomic and phylogenetic relationships of three species of Acanthocyclops (Acanthocyclops trajani, Acanthocyclops einslei and Acanthocyclops vernalis) inhabiting continental Europe. Morphological indices subjected to principal component analysis (PCA) separated sample populations into three distinct clusters corresponding with the taxonomic status of the species analysed. In addition, the taxonomy status of A. trajani and A. einslei was in agreement with molecular data; however, the intraspecific variation in sequences of 12S rRNA was lower in contrast to specimens morphologically determined as A. vernalis, which were divided into two deeply divergent clades, based on mtDNA sequence divergences. Moreover, high sequence divergence (26%) between these clades indicated the existence of another species that may not be a sister taxon of A. vernalis s.s. Results point to the need for further taxonomic work on Acanthocyclops.
Martin Hulák - One of the best experts on this subject based on the ideXlab platform.
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molecular and morphological patterns across Acanthocyclops vernalis robustus species complex copepoda cyclopoida
Zoologica Scripta, 2010Co-Authors: Martin Bláha, Martin Hulák, Jana Slouková, Jakub TěšitelAbstract:Blaha, M., Hulak, M., Sloukova, J. & Těsitel, J. (2010). Molecular and morphological patterns across Acanthocyclops vernalis-robustus species complex (Copepoda, Cyclopoida).—Zoologica Scripta, 39, 259–268. Morphological traits within Acanthocyclops (Kiefer, 1927) are highly variable, and morphology is too constrained to give complete information of phylogenetic relationships. This study combined morphological and molecular techniques to investigate the taxonomic and phylogenetic relationships of three species of Acanthocyclops (Acanthocyclops trajani, Acanthocyclops einslei and Acanthocyclops vernalis) inhabiting continental Europe. Morphological indices subjected to principal component analysis (PCA) separated sample populations into three distinct clusters corresponding with the taxonomic status of the species analysed. In addition, the taxonomy status of A. trajani and A. einslei was in agreement with molecular data; however, the intraspecific variation in sequences of 12S rRNA was lower in contrast to specimens morphologically determined as A. vernalis, which were divided into two deeply divergent clades, based on mtDNA sequence divergences. Moreover, high sequence divergence (26%) between these clades indicated the existence of another species that may not be a sister taxon of A. vernalis s.s. Results point to the need for further taxonomic work on Acanthocyclops.
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Molecular and morphological patterns across Acanthocyclops vernalis‐robustus species complex (Copepoda, Cyclopoida)
Zoologica Scripta, 2010Co-Authors: Martin Bláha, Martin Hulák, Jana Slouková, Jakub TěšitelAbstract:Blaha, M., Hulak, M., Sloukova, J. & Těsitel, J. (2010). Molecular and morphological patterns across Acanthocyclops vernalis-robustus species complex (Copepoda, Cyclopoida).—Zoologica Scripta, 39, 259–268. Morphological traits within Acanthocyclops (Kiefer, 1927) are highly variable, and morphology is too constrained to give complete information of phylogenetic relationships. This study combined morphological and molecular techniques to investigate the taxonomic and phylogenetic relationships of three species of Acanthocyclops (Acanthocyclops trajani, Acanthocyclops einslei and Acanthocyclops vernalis) inhabiting continental Europe. Morphological indices subjected to principal component analysis (PCA) separated sample populations into three distinct clusters corresponding with the taxonomic status of the species analysed. In addition, the taxonomy status of A. trajani and A. einslei was in agreement with molecular data; however, the intraspecific variation in sequences of 12S rRNA was lower in contrast to specimens morphologically determined as A. vernalis, which were divided into two deeply divergent clades, based on mtDNA sequence divergences. Moreover, high sequence divergence (26%) between these clades indicated the existence of another species that may not be a sister taxon of A. vernalis s.s. Results point to the need for further taxonomic work on Acanthocyclops.
Jana Slouková - One of the best experts on this subject based on the ideXlab platform.
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molecular and morphological patterns across Acanthocyclops vernalis robustus species complex copepoda cyclopoida
Zoologica Scripta, 2010Co-Authors: Martin Bláha, Martin Hulák, Jana Slouková, Jakub TěšitelAbstract:Blaha, M., Hulak, M., Sloukova, J. & Těsitel, J. (2010). Molecular and morphological patterns across Acanthocyclops vernalis-robustus species complex (Copepoda, Cyclopoida).—Zoologica Scripta, 39, 259–268. Morphological traits within Acanthocyclops (Kiefer, 1927) are highly variable, and morphology is too constrained to give complete information of phylogenetic relationships. This study combined morphological and molecular techniques to investigate the taxonomic and phylogenetic relationships of three species of Acanthocyclops (Acanthocyclops trajani, Acanthocyclops einslei and Acanthocyclops vernalis) inhabiting continental Europe. Morphological indices subjected to principal component analysis (PCA) separated sample populations into three distinct clusters corresponding with the taxonomic status of the species analysed. In addition, the taxonomy status of A. trajani and A. einslei was in agreement with molecular data; however, the intraspecific variation in sequences of 12S rRNA was lower in contrast to specimens morphologically determined as A. vernalis, which were divided into two deeply divergent clades, based on mtDNA sequence divergences. Moreover, high sequence divergence (26%) between these clades indicated the existence of another species that may not be a sister taxon of A. vernalis s.s. Results point to the need for further taxonomic work on Acanthocyclops.
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Molecular and morphological patterns across Acanthocyclops vernalis‐robustus species complex (Copepoda, Cyclopoida)
Zoologica Scripta, 2010Co-Authors: Martin Bláha, Martin Hulák, Jana Slouková, Jakub TěšitelAbstract:Blaha, M., Hulak, M., Sloukova, J. & Těsitel, J. (2010). Molecular and morphological patterns across Acanthocyclops vernalis-robustus species complex (Copepoda, Cyclopoida).—Zoologica Scripta, 39, 259–268. Morphological traits within Acanthocyclops (Kiefer, 1927) are highly variable, and morphology is too constrained to give complete information of phylogenetic relationships. This study combined morphological and molecular techniques to investigate the taxonomic and phylogenetic relationships of three species of Acanthocyclops (Acanthocyclops trajani, Acanthocyclops einslei and Acanthocyclops vernalis) inhabiting continental Europe. Morphological indices subjected to principal component analysis (PCA) separated sample populations into three distinct clusters corresponding with the taxonomic status of the species analysed. In addition, the taxonomy status of A. trajani and A. einslei was in agreement with molecular data; however, the intraspecific variation in sequences of 12S rRNA was lower in contrast to specimens morphologically determined as A. vernalis, which were divided into two deeply divergent clades, based on mtDNA sequence divergences. Moreover, high sequence divergence (26%) between these clades indicated the existence of another species that may not be a sister taxon of A. vernalis s.s. Results point to the need for further taxonomic work on Acanthocyclops.
Sanda Iepure - One of the best experts on this subject based on the ideXlab platform.
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POSTNAUPLIAR ANTENNULAR DEVELOPMENT IN THE OBLIGATE SUBTERRANEAN Acanthocyclops KIEFERI (CHAPPUIS, 1925) SPECIES-GROUP (KIEFER, 1927) (COPEPODA, CYCLOPOIDA)
Studies on Freshwater Copepoda: a Volume in Honour of Bernard Dussart, 2011Co-Authors: Sanda Iepure, Ioana N. MelegAbstract:The female antennule of several cyclopid copepods of the genus Acanthocyclops Kiefer, 1927 is known to have a high degree of oligomerization in both segmentation and chaetotaxy. The present work provides information on the ontogenetic development of the antennule of three (sub-)species of Acanthocyclops accommodated in the kieferi-group, with an 11- segmented antennule in the adult female. These are, A. balcanicus bisetosus Iepure, 2001, A. milotai Iepure & Defaye, 2008, and Acanthocyclops n. sp. Iepure & Oarga (unpubl.). One developmental pattern has been observed that results in an 11-segmented antennule through several successive enlargements and the addition of segments in the proximal section of the limb as follows: the first segment adds a new segment distally and an arthrodial membrane proximally during the moult to CIII; and the second segment adds a new segment distally during the moult to CIV and proximally in the moult to CV. The same (neotenic) morphology of CV is retained in the adult. The addition of segments and the distribution of setae on each segment were compared and homologized with two subterranean representatives of the genus Diacyclops Kiefer, 1927 that share the same pattern in the adult female, i.e., the D. clandestinus (Kiefer, 1926) sensu lato and the D. languidoides (Lilljeborg, 1901) sensu lato. The position of marker elements (i.e., dorsal seta (ancestral segment XV), medial distal seta (ancestral segment XX), etc.) in various copepodid stages is used to identify homologous segments. The analyses of antennula development suggest that segment number and chaetotaxy during development are characters that are less informative for phylogenetic studies in the genera Acanthocyclops and Diacyclops.
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A New Acanthocyclops Kiefer, 1927 (Copepoda: Cyclopidae) from Caves in Apuseni Mountains (North-Western Romania)
Annales Zoologici, 2011Co-Authors: Sanda Iepure, Andreea OargaAbstract:Abstract. A new stygobite species Acanthocyclops transylvanicus sp. nov. is described from the north-western Romanian Carpathians (Apuseni Mountains) and is accommodated in the subterranean kieferi-group. Acanthocyclops transylvanicus sp. nov. resembles closely A. biarticulatus Monchenko, 1972 in the segmentation pattern of the swimming legs (3.2/3.2/3.2/3.2), but differs by the following characters: antennary second endopodite segment with 7 setae; distal articles of endopodites of P1 and P3 with 4 and 5 setae, respectively; absence of coxopodite ornamentation pattern in leg 4; leg 4 endopodite with 3-segmented appearance, but lacking a functional articulation between the second and third segment. We assume that the 2-segmented nature of the leg 4 endopodite as observed in both species is a convergent acquisition. The adult shape of the leg 4 endopodite in A. transylvanicus sp. nov. results from the simple suppression of an arthrodial membrane formation. A. transylvanicus is the ninth representative know...
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The Acanthocyclops kieferi Complex (Copepoda, Cyclopoida) from South-Eastern Europe, with Description of a New Species
Crustaceana, 2008Co-Authors: Sanda Iepure, Danielle DefayeAbstract:The Acanthocyclops kieferi (Chappuis, 1925) complex (Copepoda, Cyclopoida) includes exclusively stygobitic species, mainly widespread in the cave habitats of south-eastern Europe. A new species for the group, Acanthocyclops milotai n. sp., collected from pools supplied by percolation water in a cave in south-western Romania, is described. The new species is distinguished from its congeners by the following characters: the ornamentation pattern of the basis of the antenna with four spinules placed in an arch; the coxa of leg 4 with four spinules on its distal margin; furcal rami divergent, about 2.2 times as long as wide, with the lateralmost, terminal furcal seta 1.14 times as long as the medialmost one, and these both setiform. Inter-populational variability of some characters in the new species such as the shape of the anal operculum and the ornamentation of the coxa of leg P4 are discussed. Furthermore, the characters generally used to differentiate the taxa of the kieferi group are re-examined and discussed, and a brief description of the adaptive traits of these species to the groundwater is given. Biogeographical and ecological considerations about the kieferi species-complex in Romanian groundwater habitats are also mentioned
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THE Acanthocyclops KIEFERI COMPLEX (COPEPODA, CYCLOPOIDA) FROM SOUTH-EASTERN EUROPE, WITH DESCRIPTION OF A NEW SPECIES
Crustaceana, 2008Co-Authors: Danielle Defaye, Sanda IepureAbstract:[The Acanthocyclops kieferi (Chappuis, 1925) complex (Copepoda, Cyclopoida) includes exclusively stygobitic species, mainly widespread in the cave habitats of south-eastern Europe. A new species for the group, Acanthocyclops milotai n. sp., collected from pools supplied by percolation water in a cave in south-western Romania, is described. The new species is distinguished from its congeners by the following characters: the ornamentation pattern of the basis of the antenna with four spinules placed in an arch; the coxa of leg 4 with four spinules on its distal margin; furcal rami divergent, about 2.2 times as long as wide, with the lateralmost, terminal furcal seta 1.14 times as long as the medialmost one, and these both setiform. Inter-populational variability of some characters in the new species such as the shape of the anal operculum and the ornamentation of the coxa of leg P4 are discussed. Furthermore, the characters generally used to differentiate the taxa of the kieferi group are re-examined and discussed, and a brief description of the adaptive traits of these species to the groundwater is given. Biogeographical and ecological considerations about the kieferi species-complex in Romanian groundwater habitats are also mentioned. Le complexe Acanthocyclops kieferi (Chappuis, 1925) est compose d'especes stygobiontes largement repandues dans les habitats des grottes de l'Europe de l'Est. Une nouvelle espece de ce groupe, A. milotai n. sp., trouvee dans des bassins remplis d'eau de percolation d'une grotte du sud-ouest de la Roumanie, est decrite. La nouvelle espece se distingue de ses congeneres par les caracteres suivants: l'ornementation de l'antenne avec 3 spinules disposees en arc sur le basipodite et celle du coxopodite de P4, avec 4 spinules sur son extremite distale; les rames furcales divergentes, 2,2 fois plus longues que larges et la soie furcale terminale la plus laterale 1,14 fois plus longue que celle plus mediane, les deux setiformes. La variabilite intra-populationnelle de certains caracteres chez la nouvelle espece, comme la forme de l'opercule anal et l'ornementation du coxopodite de P4 est brievement discutee. Les caracteres generalement utilises pour differencier les taxons de ce groupe sont re-examines et discutes, et une courte description de leurs traits adaptatifs est donnee. Les caracteres biogeographiques et ecologiques de la nouvelle espece et du complexe A. kieferi dans les eaux souterraines de Roumanie sont brievement discutes., The Acanthocyclops kieferi (Chappuis, 1925) complex (Copepoda, Cyclopoida) includes exclusively stygobitic species, mainly widespread in the cave habitats of south-eastern Europe. A new species for the group, Acanthocyclops milotai n. sp., collected from pools supplied by percolation water in a cave in south-western Romania, is described. The new species is distinguished from its congeners by the following characters: the ornamentation pattern of the basis of the antenna with four spinules placed in an arch; the coxa of leg 4 with four spinules on its distal margin; furcal rami divergent, about 2.2 times as long as wide, with the lateralmost, terminal furcal seta 1.14 times as long as the medialmost one, and these both setiform. Inter-populational variability of some characters in the new species such as the shape of the anal operculum and the ornamentation of the coxa of leg P4 are discussed. Furthermore, the characters generally used to differentiate the taxa of the kieferi group are re-examined and discussed, and a brief description of the adaptive traits of these species to the groundwater is given. Biogeographical and ecological considerations about the kieferi species-complex in Romanian groundwater habitats are also mentioned. Le complexe Acanthocyclops kieferi (Chappuis, 1925) est compose d'especes stygobiontes largement repandues dans les habitats des grottes de l'Europe de l'Est. Une nouvelle espece de ce groupe, A. milotai n. sp., trouvee dans des bassins remplis d'eau de percolation d'une grotte du sud-ouest de la Roumanie, est decrite. La nouvelle espece se distingue de ses congeneres par les caracteres suivants: l'ornementation de l'antenne avec 3 spinules disposees en arc sur le basipodite et celle du coxopodite de P4, avec 4 spinules sur son extremite distale; les rames furcales divergentes, 2,2 fois plus longues que larges et la soie furcale terminale la plus laterale 1,14 fois plus longue que celle plus mediane, les deux setiformes. La variabilite intra-populationnelle de certains caracteres chez la nouvelle espece, comme la forme de l'opercule anal et l'ornementation du coxopodite de P4 est brievement discutee. Les caracteres generalement utilises pour differencier les taxons de ce groupe sont re-examines et discutes, et une courte description de leurs traits adaptatifs est donnee. Les caracteres biogeographiques et ecologiques de la nouvelle espece et du complexe A. kieferi dans les eaux souterraines de Roumanie sont brievement discutes.]
