Search results for "Digenea"
showing 10 items of 49 documents
Evolutionary relationships between digeneans of the family Brachycladiidae Odhner, 1905 and their marine mammal hosts: A cophylogenetic study.
2016
Cophylogenetic studies examine the congruence between host and parasite phylogenies. There are few studies that quantify the relative contribution of coevolutionary events, i.e. duplication, loss, failure-to-diverge, host-switching and spreading in trophically-transmitted parasites at the marine realm. We addressed this issue in the Brachycladiidae, a cosmopolitan digenean family specific to marine mammals. We used, for the first time, distance-based and event-based methods to explicitly test the coevolutionary events that have shaped the current brachycladiid-marine mammal associations. Parasite phylogeny was constructed using mtDNA ND3 sequences of nine brachycladiid species, and host phy…
Infection, specificity and host manipulation of Australapatemon sp. (Trematoda, Strigeidae) in two sympatric species of leeches (Hirudinea)
2017
SUMMARYFactors that drive parasite specificity and differences in infection dynamics among alternative host species are important for ecology and evolution of host–parasite interactions, but still often poorly known in natural systems. Here, we investigated spatiotemporal dynamics of infection, host susceptibility and parasite-induced changes in host phenotype in a rarely explored host–parasite system, theAustralapatemonsp. trematode infecting two sympatric species of freshwater leeches,Erpobdella octoculataandHelobdella stagnalis. We show significant variation in infection abundance between the host species in both space and time. Using experimental infections, we also show that most of th…
In vivo fluorescent cercariae reveal the entry portals of Cardiocephaloides longicollis (Rudolphi, 1819) Dubois, 1982 (Strigeidae) into the gilthead …
2019
Background Despite their complex life-cycles involving various types of hosts and free-living stages, digenean trematodes are becoming recurrent model systems. The infection and penetration strategy of the larval stages, i.e. cercariae, into the fish host is poorly understood and information regarding their entry portals is not well-known for most species. Cardiocephaloides longicollis (Rudolphi, 1819) Dubois, 1982 (Digenea, Strigeidae) uses the gilthead seabream (Sparus aurata L.), an important marine fish in Mediterranean aquaculture, as a second intermediate host, where they encyst in the brain as metacercariae. Labelling the cercariae with in vivo fluorescent dyes helped us to track the…
Heterophyid trematodes (Digenea) from penguins: A new species of Ascocotyle Looss, 1899, first description of metacercaria of Ascocotyle (A.) patagon…
2019
Two species of heterophyid trematodes were found in the Magellanic penguin, Spheniscus magellanicus (Forster), from Patagonia, Argentina. Ascocotyle (Ascocotyle) patagoniensis Hernández-Orts et al. (2012) is re-described based on new, properly fixed specimens (original material from South American sea lion, Otaria flavescens Shaw, was from frozen hosts). Metacercariae of this species are reported and described for the first time from the heart of the silversides, Odontesthes argentinensis (Valenciennes) and O. smitti (Lahille), from Patagonia. Ascocotyle (Phagicola) cameliae n. sp. is described from the intestine of S. magellanicus. The new species is placed into the subgenus Phagicola Faus…
Description of embryonic development and ultrastructure in miracidia ofCardiocephaloides longicollis(Digenea, Strigeidae) in relation to active host …
2017
The functional ultrastructure and embryonic development of miracidia in naturally released eggs of the trematode Cardiocephaloides longicollis were studied using light and transmission electron microscopy. This species has operculated eggs and embryogenesis occurs in the marine environment before an actively infecting ciliated miracidium hatches. Six different developmental stages were identified. The lack of pores in the eggshell indicates its impermeability and the miracidium's dependency on glycogen nutritive reserves, contained in numerous vitellocytes in early embryos. As the development advances, these merge into larger vitelline vacuoles that encircle the miracidium and may aid its h…
Redescription ofOdhneriella subtila (Skrjabin, 1959) (Digenea: Campulidae) from the intestine ofGlobicephala melaena (Traill, 1809) (Cetacea: Delphin…
1989
During parasitological investigations of long-finned pilot whales,Globicephala melaena (Traill, 1809), in the Faroe Islands, the trematode speciesOdhneriella subtila (Digenea: Campulidae), parasitising the small intestine, was detected. Skrjabin's (1959) original description of this species was based on a single individual. The collection and availability for study of several thousands of specimens permitted the redescription of this campulid and the noting of some new morphological characters. This trematode is reported for the first time from the long-finned pilot whale, and the Atlantic Ocean is a new locality record.
Contrasting temperature responses in seasonal timing of cercariae shedding by Rhipidocotyle trematodes
2022
AbstractGlobal warming is likely to lengthen the seasonal duration of larval release by parasites. We exposed freshwater mussel hosts, Anodonta anatina, from 2 high-latitude populations to high, intermediate and low temperatures throughout the annual cercarial shedding period of the sympatric trematodes Rhipidocotyle fennica and R. campanula, sharing the same transmission pathway. At the individual host level, under warmer conditions, the timing of the cercarial release in both parasite species shifted towards seasonally earlier period while its duration did not change. At the host population level, evidence for the lengthening of larvae shedding period with warming was found for R. fennica…
Host specificity ofOschmarinella rochebruniandBrachycladium atlanticum(Digenea: Brachycladiidae) in five cetacean species from western Mediterranean …
2010
AbstractWe investigated patterns of specificity of liver flukes (fam. Brachycladiidae) in a community of cetaceans from the western Mediterranean. The liver and pancreas of 103 striped dolphins,Stenella coeruleoalba, 18 Risso's dolphins,Grampus griseus, 14 bottlenose dolphins,Tursiops truncatus, 8 common dolphins,Delphinus delphis, and 5 long-finned pilot whales,Globicephala melas, were analysed for brachycladiid species. Two species were found:Oschmarinella rochebruniin striped dolphins (prevalence (P): 61.2%; mean intensity (MI) (95% CI): 34.2 (25.7–45.6)), andBrachycladium atlanticumin striped dolphins (P: 39.8%; MI: 7.1 (4.8–13.1)) and a single individual of common dolphin (P: 12.5%; in…
Parasite community diversity in two Mediterranean labrid fishes Symphodus tinea and Labrus merula
1994
Examination of 111 peacock wrasse [Symphodus tinea (L.)] and 97 brown wrasse (Labrus merula L.) from the Valencian coast (Spain) yielded 24 metazoan parasite species (11 Digenea, three Cestoda, four Nematoda. one Acanlhocephala, five Crustacea). Eighteen species were from 5. tinea and 17 from L. merula; 11 of the 24 species were common to both hosts. Brillouin's diversity index, was applied to fully censused parasite infracommunities. This is the first time that all the metazoan parasites (internal and external) in any position in the host have been analysed for diversity. High values of prevalence, intensity, and diversity parameters indicate that these labrid fishes support diverse parasi…
Distribution of Pholeter gastrophilus (Digenea) within the stomach of four odontocete species: the role of the diet and digestive physiology of hosts
2005
We compared the distribution of the digenean Pholeter gastrophilus in the stomach of 27 harbour porpoises, Phocoena phocoena, 27 striped dolphins, Stenella coeruleoalba, 18 bottlenose dolphins, Tursiops truncatus, and 100 long-finned pilot whales, Globicephala melas. The stomach of these species is composed of 4 chambers of different size, structure and function. In all species, P. gastrophilus was largely restricted to the glandular region of the stomach, but the parasite tended to favour the fundic chamber in bottlenose dolphins and harbour porpoises, the pyloric chamber in pilot whales, and none in striped dolphins. However, predictability at infrapopulation level was generally low, sugg…