Search results for "Schistocephalus"
showing 6 items of 6 documents
Cannibalism facilitates gigantism in a nine-spined stickleback (Pungitius pungitius) population
2016
Cannibalism is a taxonomically widespread phenomenon that can fundamentally affect the structure and stability of aquatic communities, including the emergence of a bimodal size distribution (“dwarfs” and “giants”) in fish populations. Emergence of giants could also be driven or facilitated by parasites that divert host resources from reproduction to growth. We studied the trophic ecology of giant nine-spined sticklebacks (Pungitius pungitius) in a Finnish pond to evaluate the hypotheses that gigantism in this population would be facilitated by cannibalism and/or parasitic infections by Schistocephalus pungitii cestode. Stomach content analyses revealed an initial ontogenetic dietary shift f…
DNA barcoding reveals different cestode helminth species in northern European marine and freshwater ringed seals
2021
Three subspecies of the ringed seal (Pusa hispida) are found in northeastern Europe: P. h. botnica in the Baltic Sea, P. h saimensis in Lake Saimaa in Finland, and P. h. ladogensis in Lake Ladoga in Russia. We investigated the poorly-known cestode helminth communities of these closely related but ecologically divergent subspecies using COI barcode data. Our results show that, while cestodes from the Baltic Sea represent Schistocephalus solidus, all worms from the two lakes are identified as Ligula intestinalis, a species that has previously not been reported from seals. The observed shift in cestode communities appears to be driven by differential availability of intermediate fish host spec…
The Leonian Stage (early Middle Cambrian): a unit for Cambrian correlation in the Mediterranean subprovince
1999
The Leonian (early Middle Cambrian) regional Stage of Iberia is revised from a lithostratigraphic and biostratigraphic point of view in order to propose it as a chronostratigraphic unit for the Mediterranean subprovince (outcrops in Spain, France, Italy, Germany, Morocco and Turkey). This revision now permits a correlation of the Leonian Stage with the other early Middle Cambrian regional Stages. For this correlation the first appearance datum (FAD) of Eoparadoxides mureroensis, Macannaia spp., Schistocephalus antiquus and Oryctocara granulata are employed for the lower boundary; while the FADs of Badulesia tenera, Ctenocephalus (Hartella) spp., Parasolenopleura aculeata and Triplagnostus g…
Consistent isotopic differences between Schistocephalus spp. parasites and their stickleback hosts
2015
Published version available at http://dx.doi.org/10.3354/dao02893 Parasite−host systems show markedly variable patterns in isotopic fractionation: parasites can be either depleted or enriched in 15N and 13C as compared to their hosts. However, it remains unknown whether isotopic fractionation patterns are similar in comparable parasite−host systems from markedly different ecosystems. Results of this study show that large-sized Schistocephalus spp. endoparasites are consistently depleted in 15N (by on average −2.13 to −2.20‰) as compared to their nine-spined stickleback Pungitius pungitius and three-spined stickleback Gasterosteus aculeatus hosts. The differences between parasites and host f…
Combining stable isotope and intestinal parasite information to evaluate dietary differences between individual ringed seals (Phoca hispida botnica)
2006
The diet and foraging behaviour of nine individual Baltic ringed seals ( Phoca hispida botnica Gmelin, 1785) in the Bothnian Bay were studied by combining results from stable isotope analyses (δ13C and δ15N) with data on intestinal parasites whose occurrence varied among the fish hosts. The patterns of infection with three acanthocephalan parasites, Corynosoma semerme (Forssell, 1904), Corynosoma magdaleni Montreuil, 1958, and Corynosoma strumosum (Rudolphi, 1802), and with a cestode larva, Schistocephalus solidus (Müller, 1776), were examined. The ringed seals become infected with these intestinal parasites by feeding on the fish hosts and hence have different parasite species and differe…
Segregation and co-occurrence of larval cestodes in freshwater fishes in the Bothnian Bay, Finland
1992
SUMMARYTwo autogenic (Triaenophorus crassus and T. nodulosus) and four allogenic (Diphyllobothrium latum, D. dendriticum, D. ditremum and Schistocephalus solidus) larval cestode species were found in 13 out of 31 fish species studied from the Bothnian Bay, NE Baltic. Gasterosteus aculeatus was the most heavily infected fish with 4 larval cestode species; for two of them (D. ditremum and S. solidus) the three-spined stickleback was found to be the required fish intermediate host. Among allogenic cestode species, those restricted to different definitive host species segregated their larval population in relation to the fish host, while, for example, D. ditremum and S. solidus, both maturing i…