The Experts below are selected from a list of 81 Experts worldwide ranked by ideXlab platform
Steffen U Pauls - One of the best experts on this subject based on the ideXlab platform.
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molecular data and species distribution models reveal the pleistocene history of the mayfly ameletus inopinatus ephemeroptera Siphlonuridae 1
Freshwater Biology, 2011Co-Authors: Kathrin Theissinger, Miklos Balint, Peter Haase, Jes Johannesen, Irina Laube, Steffen U PaulsAbstract:SUMMARY 1. We investigated the Pleistocene and Holocene history of the rare mayfly Ameletus inopinatus EATON 1887 (Ephemeroptera: Siphlonuridae) in Europe. We used A. inopinatus as a model species to explore the phylogeography of montane, cold-tolerant aquatic insects with arctic–alpine distributions. 2. Using species distribution models, we developed hypotheses about the species demographic history in Central Europe and the recolonisation history of Fennoscandia. We tested these hypotheses using mitochondrial cytochrome oxidase I (mtCOI) sequence data and compared our genetic results with previously generated microsatellite data to explore genetic diversity distributions of A. inopinatus. 3. We observed old lineages, deep splits and almost complete lineage sorting of mtCOI sequences among mountain ranges. These results support a periglacial survival, i.e. persistence at the periphery of Pleistocene glaciers in Central Europe. 4. There was strong differentiation between the Fennoscandian and all other populations, indicating that Fennoscandia was recolonised from a refugium not accounted for in our sampling. High degrees of population genetic structure within the northern samples suggest that Fennoscandia was recolonised by more than one lineage. However, this structure was not apparent in previously published microsatellite data, consistent with secondary contact without sexual incompatibility or with sex-biased dispersal. 5. Our demographic analyses indicate that (i) the separation of northern and Central European lineages occurred during the early Pleistocene; (ii) Central European populations have persisted independently throughout the Pleistocene and (iii) the species extended its range about 150 000 years ago.
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isolation and characterization of 10 highly polymorphic di and trinucleotide microsatellite markers in the mayfly ameletus inopinatus ephemeroptera Siphlonuridae
Molecular Ecology Resources, 2008Co-Authors: Kathrin Theissinger, Kevin A Feldheim, Julia Taubmann, Alfred Seitz, Steffen U PaulsAbstract:We describe the isolation of ten polymorphic microsatellite loci from the mayfly Ameletus inopinatus. Loci had di- or trinucleotide repeat motifs and were highly variable with three to 17 alleles (mean = 7.15). Observed heterozygosity ranged from 0.143 to 0.905. One locus (Ami_202) showed significant deviation from Hardy–Weinberg equilibrium in one population, but no evidence for null alleles. One locus (Ami_73) was significantly linked with three other loci. The remaining nine loci should prove highly informative for population genetic studies.
Kathrin Theissinger - One of the best experts on this subject based on the ideXlab platform.
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molecular data and species distribution models reveal the pleistocene history of the mayfly ameletus inopinatus ephemeroptera Siphlonuridae 1
Freshwater Biology, 2011Co-Authors: Kathrin Theissinger, Miklos Balint, Peter Haase, Jes Johannesen, Irina Laube, Steffen U PaulsAbstract:SUMMARY 1. We investigated the Pleistocene and Holocene history of the rare mayfly Ameletus inopinatus EATON 1887 (Ephemeroptera: Siphlonuridae) in Europe. We used A. inopinatus as a model species to explore the phylogeography of montane, cold-tolerant aquatic insects with arctic–alpine distributions. 2. Using species distribution models, we developed hypotheses about the species demographic history in Central Europe and the recolonisation history of Fennoscandia. We tested these hypotheses using mitochondrial cytochrome oxidase I (mtCOI) sequence data and compared our genetic results with previously generated microsatellite data to explore genetic diversity distributions of A. inopinatus. 3. We observed old lineages, deep splits and almost complete lineage sorting of mtCOI sequences among mountain ranges. These results support a periglacial survival, i.e. persistence at the periphery of Pleistocene glaciers in Central Europe. 4. There was strong differentiation between the Fennoscandian and all other populations, indicating that Fennoscandia was recolonised from a refugium not accounted for in our sampling. High degrees of population genetic structure within the northern samples suggest that Fennoscandia was recolonised by more than one lineage. However, this structure was not apparent in previously published microsatellite data, consistent with secondary contact without sexual incompatibility or with sex-biased dispersal. 5. Our demographic analyses indicate that (i) the separation of northern and Central European lineages occurred during the early Pleistocene; (ii) Central European populations have persisted independently throughout the Pleistocene and (iii) the species extended its range about 150 000 years ago.
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isolation and characterization of 10 highly polymorphic di and trinucleotide microsatellite markers in the mayfly ameletus inopinatus ephemeroptera Siphlonuridae
Molecular Ecology Resources, 2008Co-Authors: Kathrin Theissinger, Kevin A Feldheim, Julia Taubmann, Alfred Seitz, Steffen U PaulsAbstract:We describe the isolation of ten polymorphic microsatellite loci from the mayfly Ameletus inopinatus. Loci had di- or trinucleotide repeat motifs and were highly variable with three to 17 alleles (mean = 7.15). Observed heterozygosity ranged from 0.143 to 0.905. One locus (Ami_202) showed significant deviation from Hardy–Weinberg equilibrium in one population, but no evidence for null alleles. One locus (Ami_73) was significantly linked with three other loci. The remaining nine loci should prove highly informative for population genetic studies.
Steve Burian - One of the best experts on this subject based on the ideXlab platform.
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life history aspects of the mayfly siphlonurus typicus ephemeroptera Siphlonuridae with a new application for measuring nymphal development and growth
Hydrobiologia, 2003Co-Authors: Ely Kosnicki, Steve BurianAbstract:Little is known about the life history of mayflies that inhabit temporary ponds. The purpose of this study was to observe and quantify life histories attributes of Siphlonurus typicus, which is known to reside in temporary ponds. Weekly samples of nymphs were taken from two temporary ponds in eastern Connecticut from March to June, 1999. Individuals were graded into 11 maturity classes, based on developmental characteristics, as a means of predicting population maturity rates. Head capsule widths (HCWs) were used to determine if growth occurred between maturity classes. Degree days were found to be an excellent predictor for population maturity (r2=0.963, p<0.0001). Nymphs that hatched earlier in the year had larger HCWs than nymphs that hatched later in the year, possibly because of different temperature regimes. The University of Connecticut Forest pond (UCF) population matured faster than the Merrow Meadows pond (MER) population, but both sexes of the UCF population tended to be smaller than their counter parts from the MER population. Sex ratios were female bias for the UCF population (1.35:1), but were not different for the MER population. Adult emergence and mating occurred from 27 May to 21 June. There was a positive relationship between number of eggs per female and female body length. Oviposition at both sites occurred directly on the ponds, pond inlets, and outlets, indicating that pond populations were the result of local migrants as well as permanent residents. Temperature was a determining factor of maturity and fecundity for Siphlonurus typicus.
Ely Kosnicki - One of the best experts on this subject based on the ideXlab platform.
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dehydration tolerance of the temporary pond mayfly siphlonurus typicus ephemeroptera Siphlonuridae
Journal of Freshwater Ecology, 2005Co-Authors: Ely KosnickiAbstract:ABSTRACT Nymphs of the mayfly Siphlonurus typicus were exposed to simulated drought conditions in the laboratory. After environmental water gradually disappeared, chance of survival was analyzed by elapsed time, sex, and level of maturity. Individuals have a 45% chance of survival after being out of standing water for 24 h.
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life history aspects of the mayfly siphlonurus typicus ephemeroptera Siphlonuridae with a new application for measuring nymphal development and growth
Hydrobiologia, 2003Co-Authors: Ely Kosnicki, Steve BurianAbstract:Little is known about the life history of mayflies that inhabit temporary ponds. The purpose of this study was to observe and quantify life histories attributes of Siphlonurus typicus, which is known to reside in temporary ponds. Weekly samples of nymphs were taken from two temporary ponds in eastern Connecticut from March to June, 1999. Individuals were graded into 11 maturity classes, based on developmental characteristics, as a means of predicting population maturity rates. Head capsule widths (HCWs) were used to determine if growth occurred between maturity classes. Degree days were found to be an excellent predictor for population maturity (r2=0.963, p<0.0001). Nymphs that hatched earlier in the year had larger HCWs than nymphs that hatched later in the year, possibly because of different temperature regimes. The University of Connecticut Forest pond (UCF) population matured faster than the Merrow Meadows pond (MER) population, but both sexes of the UCF population tended to be smaller than their counter parts from the MER population. Sex ratios were female bias for the UCF population (1.35:1), but were not different for the MER population. Adult emergence and mating occurred from 27 May to 21 June. There was a positive relationship between number of eggs per female and female body length. Oviposition at both sites occurred directly on the ponds, pond inlets, and outlets, indicating that pond populations were the result of local migrants as well as permanent residents. Temperature was a determining factor of maturity and fecundity for Siphlonurus typicus.
Muhammad Nor Hisyam Bin Kamarudin - One of the best experts on this subject based on the ideXlab platform.
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Potensi makroinvertebrat bentik sebagai penunjuk biologi di sungai ikan, Hulu Terengganu, Terengganuv
Sains Malaysiana Penerbit Universiti Kebangsaan Malaysia, 2015Co-Authors: Muhammad Nor Hisyam Bin KamarudinAbstract:Suatu kajian telah dijalankan untuk menentukan potensi makroinvertebrat bentik sebagai penunjuk biologi di hulu Sungai Ikan, Terengganu. Sebanyak lima stesen pensampelan telah dipilih untuk pensampelan makroinvertebrat bentik dan analisis kualiti air. Pensampelan makroinvertebrat bentik telah dilakukan menggunakan jaring Surber dan analisis kualiti air dilakukan menurut kaedah APHA. Piawaian Kualiti Air Kebangsaan (NWQS) telah digunakan untuk menilai parameter kualiti air di kawasan kajian dan hasil menunjukkan Sungai Ikan berada dalam keadaan baik iaitu kelas I hingga II. Ujian ANOVA satu hala menunjukkan bahawa kesemua parameter air yang diuji adalah seragam di sepanjang kawasan kajian (p>0.05, ?=0.05). Sebanyak 2 filum, 3 kelas, 8 order, 39 famili dan 1353 individu telah dikenal pasti dan didominasi oleh famili Baetidae, Siphlonuridae, Simuliidae, Chironomidae dan Elmidae. Famili dominan didapati hadir pada hampir kesemua stesen pensampelan. Memandangkan kualiti air adalah baik dan tidak berubah sepanjang kawasan kajian, ujian CCA dilakukan untuk memperlihatkan faktor persekitaran lain yang mempengaruhi sebaran makroinvertebrat terutamanya famili dominan. Hasil ujian CCA menunjukkan pengaruh persekitaran yang khusus terhadap famili tertentu dan mempunyai pengaruh yang kuat terhadap sebaran makroinvertebrat bentik. Ujian korelasi menunjukkan batuan besar mempunyai pengaruh besar terhadap sebaran famili Baetidae, Siphlonuridae dan sub-famili Orthocladiinae, manakala komposisi pasir pula mempunyai pengaruh terhadap famili Elmidae. Hasil kajian ini menunjukkan dalam ekosistem yang bersih, faktor persekitaran habitat adalah kritikal untuk diambil kira dalam menentukan taksa tertentu yang sesuai digunakan sebagai penunjuk biologi ekosistem sungai rekreasi