Topic
Rhithrogena
About: Rhithrogena is a research topic. Over the lifetime, 83 publications have been published within this topic receiving 2069 citations.
Papers published on a yearly basis
Papers
TL;DR: In this article, the effects of a large flood on the invertebrate community in a prealpine Swiss river, the River Necker, were compared with a phenomenological study.
Abstract: 1. The crucial point of disturbance experiments in streams is the extent to which they can simulate a natural spate. Ideally, disturbance experiments should proceed side by side with a phenomenological study to allow a direct comparison. In the present study conducted in a prealpine Swiss river, the River Necker, fortuitous events made such a comparison possible.
2. In summer 1994, we took Surber samples one day before and on several sampling dates after a major flood (recurrence interval ≈ 5 years), which was followed by a long period of uniform discharge in a river characterized by frequent spates. Beginning 19 days after this flood, patches of the stream bed (≈ 9 m2) were physically disturbed by kicking and raking.
3. The degrees of reduction in the total number of individuals and the dominant taxa were similar after both types of disturbance, as were the recolonization patterns of Rhithrogena spp., Leuctra spp. and Hydracarina. Chironomidae, Baetis spp., Simuliidae, Pentaneurini and Corynoneura/Thienemanniella spp. showed a distinct lag phase after the flood before recolonization began, whereas there was no such lag phase after the experiment. Therefore, the time needed to recover to pre-flood densities was longer for these taxa. Nevertheless, recolonization rates and patterns after the lag phase were similar to those after the experimental disturbance.
4. Size-class measurements indicated that recruitment from egg hatching may have been more important after the flood than after the experimental disturbance for Rhithrogena spp., but not for Chironomidae, Baetis spp., Simuliidae, Pentaneurini and Leuctra spp. Invertebrate drift was probably the most important pathway of recolonization after both types of disturbance.
5. Our experiment allowed a realistic simulation of several important effects of the large flood on the invertebrate community. Smaller spates that induce substratum movement at a spatial scale similar to our experimental plots are much more common than large floods in the River Necker. For these spates, our experiment should provide an even more realistic simulation of natural disturbance.
124 citations
TL;DR: The population genetic structure of 3 species of alpine stream insects among major drainages of the Swiss Alps, among streams within each drainage, and within single streams is investigated to suggest that genetic population structure reflects a lack of equilibrium between gene flow and genetic drift.
Abstract: Estimating scales of dispersal for benthic macroinvertebrates using neutral genetic markers requires consideration of genetic, demographic, and historical influences on population genetic structure. We used allozyme electrophoresis to investigate the population genetic structure of 3 species of alpine stream insects among major drainages of the Swiss Alps (Rhine, Inn, and Ticino rivers), among streams within each drainage, and within single streams. Within streams we examined reaches that were fragmented by lakes or resevoirs and unfragmented reaches. Rhithrogena loyolaea (Heptageniidae) exhibited little genetic differentiation (θ) within (θ = 0.01-0.03) and among (θ = 0.02-0.03) streams but significant differentiation among drainages (θ = 0.08), suggesting that dispersal occurs among stream fragments and among stream valleys. Allogamus auricollis (Limnephilidae) did not exhibit genetic differentiation at any scale, suggesting that dispersal occurs throughout the geographical range of the study. In contra...
109 citations
TL;DR: The DNA taxonomy developed here lays the groundwork for a future revision of the important but cryptic Rhithrogena genus in Europe, using a widespread sampling scheme of Alpine species that included 22 type localities, general mixed Yule-coalescent model analysis of one standard mtDNA marker and one newly developed nDNA marker, and morphological identification where possible.
Abstract: Aquatic larvae of many Rhithrogena mayflies (Ephemeroptera) inhabit sensitive Alpine environments. A number of species are on the IUCN Red List and many recognized species have restricted distributions and are of conservation interest. Despite their ecological and conservation importance, ambiguous morphological differences among closely related species suggest that the current taxonomy may not accurately reflect the evolutionary diversity of the group. Here we examined the species status of nearly 50% of European Rhithrogena diversity using a widespread sampling scheme of Alpine species that included 22 type localities, general mixed Yule-coalescent (GMYC) model analysis of one standard mtDNA marker and one newly developed nDNA marker, and morphological identification where possible. Using sequences from 533 individuals from 144 sampling localities, we observed significant clustering of the mitochondrial (cox1) marker into 31 GMYC species. Twenty-one of these could be identified based on the presence of topotypes (expertly identified specimens from the species' type locality) or unambiguous morphology. These results strongly suggest the presence of both cryptic diversity and taxonomic oversplitting in Rhithrogena. Significant clustering was not detected with protein-coding nuclear PEPCK, although nine GMYC species were congruent with well supported terminal clusters of nDNA. Lack of greater congruence in the two data sets may be the result of incomplete sorting of ancestral polymorphism. Bayesian phylogenetic analyses of both gene regions recovered four of the six recognized Rhithrogena species groups in our samples as monophyletic. Future development of more nuclear markers would facilitate multi-locus analysis of unresolved, closely related species pairs. The DNA taxonomy developed here lays the groundwork for a future revision of the important but cryptic Rhithrogena genus in Europe.
108 citations
TL;DR: In metal mixtures, the toxicities of the three metals were less than additive on a concentration‐addition basis, and with swim‐up trout fry, a pattern of decreasing resistance with increasing fish size was observed.
Abstract: The authors conducted 150 tests of the acute toxicity of resident fish and invertebrates to Cd, Pb, and Zn, separately and in mixtures, in waters from the South Fork Coeur d'Alene River watershed, Idaho, USA. Field-collected shorthead sculpin (Cottus confusus), westslope cutthroat trout (Oncorhynchus clarkii lewisi), two mayflies (Baetis tricaudatus and Rhithrogena sp.), a stonefly (Sweltsa sp.), a caddisfly (Arctopsyche sp.), a snail (Gyraulus sp.), and hatchery rainbow trout (Oncorhynchus mykiss), were tested with all three metals. With Pb, the mayflies (Drunella sp., Epeorus sp., and Leptophlebiidae), a Simuliidae black fly, a Chironomidae midge, a Tipula sp. crane fly, a Dytiscidae beetle, and another snail (Physa sp.), were also tested. Adult westslope cutthroat trout were captured to establish a broodstock to provide fry of known ages for testing. With Cd, the range of 96-h median effect concentrations (EC50s) was 0.4 to >5,329 µg/L, and the relative resistances of taxa were westslope cutthroat trout ≈ rainbow trout ≈ sculpin << other taxa; with Pb, EC50s ranged from 47 to 3,323 µg/L, with westslope cutthroat trout < rainbow trout < other taxa; and with Zn, EC50s ranged from 21 to 3,704 µg/L, with rainbow trout < westslope cutthroat trout ≈ sculpin << other taxa. With swim-up trout fry, a pattern of decreasing resistance with increasing fish size was observed. In metal mixtures, the toxicities of the three metals were less than additive on a concentration-addition basis.
104 citations
TL;DR: In this article, changes in water chemistry, benthic organic matter (BOM), and macroinvertebrates were examined in four different glacial streams over an annual cycle.
Abstract: 1. Changes in water chemistry, benthic organic matter (BOM), and macroinvertebrates were examined in four different glacial streams over an annual cycle. The streams experienced strong seasonal changes in water chemistry that reflected temporal changes in the influence from the source glacier, especially in water turbidity, particulate phosphorus and conductivity.
2. Nitrogen concentrations were high (nitrate-N values were 130–274 μg L–1), especially during spring snowmelt runoff. Benthic organic matter attained >600 g m–2 dry mass at certain times, peaks being associated with seasonal blooms of the alga Hydrurus foetidus.
3. Macroinvertebrate taxon richness was two to three times higher (also numbers and biomass) in winter than summer suggesting winter may be a more favourable period for these animals. Benthic densities averaged 1140–3820 ind. m–2, although peaking as high as 9000 ind. m–2. Average annual biomass ranged from 102 to 721 mg m–2, and reached >2000 mg m–2 at one site in autumn.
4. Taxa common to all sites included the dipterans Diamesa spp. and Rhypholophus sp., the plecopterans Leuctra spp. and Rhabdiopteryx alpina, and the ephemeropterans Baetis alpinus and Rhithrogena spp. Principal components analysis clearly separated winter assemblages from those found in summer.
98 citations
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Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 1 |
| 2020 | 1 |
| 2019 | 1 |
| 2018 | 3 |
| 2017 | 2 |
| 2016 | 1 |