Topic
Pisidium
About: Pisidium is a research topic. Over the lifetime, 126 publications have been published within this topic receiving 1589 citations.
Papers published on a yearly basis
Papers
TL;DR: All abundant species in the frozen substratum, except Asellus aquaticus, seemed to be well adapted to withstand overwintering in this special habitat free from predation, as the ambient temperature was below the true freezing point of most animals.
Abstract: In winter the water freezes into the substrate within considerable areas of unregulated northern rivers due to low temperature combined with a lowering of the water level. Living individuals of Nematoda, Gastropoda, Sphaeriidae, Oligochaeta, Hirudinea, Isopoda, Trichoptera and Chironomidae were found in samples of ice and frozen sediment from the bottom frozen hydrolittoral zone of the north Swedish river Vindelilven. All abundant species in the frozen substratum, except Asellus aquaticus, seemed to be well adapted to withstand overwintering in this special habitat free from predation. Generally, between 80 and 100% of enclosed animals survived thawing. Cysts or other kinds of resting stage constructions, similar to those found during drought, were common in several enclosed species. Specimens of Gyraulus acronicus, Pisidium ssp., Molanna albicans and Chironomidae survived exposure to -40C for five month in a freezing experiment. Extracellular freezing of the invertebrates overwintering in the ice is probable, as the ambient temperature was below the true freezing point of most animals. The composition of the substratum may effect the survival of animals enclosed in ice.
68 citations
TL;DR: This work reconstructed phylogenetic relationships of the Sphaeriinae, a cosmopolitan sphaeriid subfamily, using variation in nuclear ribosomal first internal transcribed spacer (ITS-1) and mitochondrial large Ribosomal subunit (16S) gene fragments to revise current sphaerine taxonomy.
66 citations
TL;DR: The patterns of speciation found in the genus Pisidium are compared to patterns in morphologically distinct molluscan groups in lakes Ohrid und Prespa and suggested scenarios of the endemic pea clam evolution within both lakes are suggested.
Abstract: The morphologically remarkable endemic fauna within ancient lakes has received much attention in the literature. More inconspicuous taxa, however, often lack detailed molecular and morphometrical examination, although their proportion of the endemic fauna of an ancient lake must not be underestimated. Consequently, a better understanding of evolutionary patterns and processes within these lakes requires more knowledge about the often-neglected inconspicuous taxa. In the present study, we focus on the notoriously cryptic pea clam genus Pisidium (Bivalvia: Sphaeriidae). Though the genus is widely distributed, most endemic species are reported only from ancient lakes, including the European ancient sister lake system of Ohrid and Prespa on the Balkan Peninsula. Here we test for the first time hypotheses on the evolution of the endemic pea clams in this European biodiversity hotspot by molecular means. Combining a broad 16S phylogeny (comprising most European pea clam species), network analyses and morphometrical analyses, we found interesting biogeographical patterns and provide evidence for cryptic species in both lakes. Furthermore, we confirmed the proposed sister-species relationship of the endemics P. edlaueri in Lake Ohrid and P. maasseni in Lake Prespa, and we suggest scenarios of the endemic pea clam evolution within both lakes. The patterns of speciation found in the genus Pisidium are compared to patterns in morphologically distinct molluscan groups in lakes Ohrid und Prespa.
60 citations
Journal Article•
56 citations
TL;DR: The gastropod Amnicola limosa and the chironomid Chironomus sp.
Abstract: The structure and diversity, including seasonal variation, and the energy budget of the benthic fauna in southern Lake Manitoba were studied and related to physical and chemical properties of the water and sediment. A total of 47 taxa were identified but 90 percent of individuals were represented by seven taxa (Candona rawsoni, Cytheromorpha fuscata, Pisidium spp., Amnicola limosa, Harnischia curtilamellata, Procladius freemani and Chironomus sp.). The spatial and temporal dynamics, dispersion patterns and life cycles of these abundant species are described.
48 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2021 | 1 |
| 2020 | 4 |
| 2017 | 7 |
| 2016 | 3 |
| 2015 | 2 |
| 2014 | 1 |