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12. Pseudoacanthocephalus lutzi (Hamann, 1891) comb. n. (Acanthocephala: Echinorhynchidae) for Acanthocephalus lutzi (Hamann, 1891), parasite of South American amphibians
- Creator:
- Arredondo, Nathalia J. and Gil de Pertierra, Alicia A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Acanthocephala, Echinorhynchidae, Acanthocephalus lutzi, Pseudoacanthocephalus, Rhinella, amphibians, and Argentina
- Language:
- English
- Description:
- Acanthocephalus lutzi (Hamann, 1891) is proposed to be transferred to the genus Pseudoacanthocephalus Petrochenko, 1956 based on the type material from Rhinella marina (L.) from Brazil and recently collected material from R. arenarum (Hensel) from Argentina. Pseudoacanthocephalus is characterised by the following features: a cylindrical trunk without spines, a cylindrical proboscis, testes in tandem, a compact cluster of cement glands, a nearly terminal male genital pore, a ventral and sub-terminal female genital pore, and egg without polar prolongations, containing a holoechinate acanthor. Pseudoacanthocephalus lutzi comb. n. has a proboscis armature of 14-18 longitudinal rows of 5-8 hooks each, with all roots formed by a posteriorly directed longitudinal spatulate sheet having a central rib, and an inconspicuous sheet directed anteriorly; a variable number (4, 5 or 6) of cement glands; a cerebral ganglion located near the base of the proboscis receptacle; digitiform to claviform lemnisci, as long as, or slightly shorter or slightly longer than the proboscis receptacle; a sigmoid-shaped posterior end in males; an egg with a conspicuous fibrillar coat; and one of the larval hooks more robust and different in shape than the others. Additionally, the type material of Acanthocephalus saopaulensis Smales, 2007 from Rhinella icterica (Spix) from Brazil and a paratype of A. caspanensis Fernández et Ibarra Vidal, 1992 from R. spinulosa (Wiegmann) from Chile were studied. Acanthocephalus saopaulensis is considered conspecific with P. lutzi and A. caspanensis is transferred to Pseudoacanthocephalus because it possesses all the characters of the genus mentioned above. The use of characters such as egg morphology and host ecology for distinguishing Acanthocephalus from Pseudoacanthocephalus is also discussed.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
13. Redescription of cystacanths of Corynosoma pseudohamanni Zdzitowiecki, 1984 (Acanthocephala: Polymorphidae) from paratenic fish hosts
- Creator:
- Mašová, Šárka and Baruš, Vlastimil
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Acanthocephala, Corynosoma pseudohamanni, redescription, morphology, James Ross Island, and Antarctica
- Language:
- English
- Description:
- Cystacanths of Corynosoma pseudohamanni Zdzitowiecki, 1984 (Palaeacanthocephala: Polymorphidae) are redescribed on the basis of specimens recovered from three species of Antarctic notothenioid fish, Trematomus bernacchii Boulenger, Gobionotothen gibberifrons (Lönnberg) and Notothenia coriiceps Richardson, collected from the Prince Gustav Channel, Antarctica. The cystacanths' morphometry and their internal anatomy including trunk muscles were studied using light and scanning electron microscopy (SEM). The characteristic features of this species such as the length of proboscis and the number of hooks (i.e. 260 hooks arranged in 20 rows with 13 hooks each, including two basal hooks) were confirmed and the intraspecific variability was evaluated. Sexual dimorphism was manifested in the shape of the hindtrunk, and the distribution and extent of the somatic armature only. SEM observations of internal anatomy revealed the detailed organization of trunk musculature.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
14. The interrelationships of metazoan parasites: a review of phylum- and higher-level hypotheses from recent morphological and molecular phylogenetic analyses
- Creator:
- Zrzavý, Jan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- phylogeny, parasitism, Myxozoa, Mesozoa, Neodermata, Myzostomida, Seisonida, Acanthocephala, Pentastomida, Nematomorpha, and Nematoda
- Language:
- English
- Description:
- Phylogeny of seven groups of metazoan parasitic groups is reviewed, based on both morphological and molecular data. The Myxozoa (=Malacosporea + Myxosporea) are most probably related to the egg-parasitic cnidarian Polypodium (Hydrozoa?: Polypodiozoa); the other phylogenetic hypotheses are discussed and the possible non-monophyly of the Cnidaria (with the Polypodiozoa-Myxozoa clade closest to the Triploblastica) is suggested. The Mesozoa is a monophyletic group, possibly closely related to the (monophyletic) Acoelomorpha; whether the Acoelomorpha and Mesozoa represent the basalmost triploblast clade(s) or a derived platyhelminth subclade may depend on rooting the tree of the Triploblastica. Position of the monophyletic Neodermata (=Trematoda + Cercomeromorpha) within the rhabditophoran flatworms is discussed, with two major alternative hypotheses about the neodermatan sister-group relationships (viz., the "neoophoran" and "revertospermatan"). The Myzostomida are not annelids but belong among the Platyzoa, possibly to the clade of animals with anterior sperm flagella (=Prosomastigozoa). The Acanthocephala represent derived syndermates ("rotifers"), possibly related to Seison (the name Pararotatoria comb. n. is proposed for Seisonida + Acanthocephala). The crustacean origin of the Pentastomida based on spermatological and molecular evidence (Pentastomida + Branchiura = Ichthyostraca) is confronted with palaeontological views favouring the pre-arthropod derivation of the pentastomids. Phylogenetic position of the nematodes within the Ecdysozoa and evolution of nematode parasitism are discussed, and the lack of relevant information about the enigmatic ectoproctan parasite Buddenbrockia is emphasised.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
15. The occurrence of Echinorhynchus salmonis Müller, 1784 in benthic amphipods in the Baltic Sea
- Creator:
- Benesh, Daniel P, Aura, Raija-Liisa, Andersin, Ann-Britt, and Valtonen, E. Tellervo
- Format:
- electronic, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitologie, parasitology, Acanthocephala, aggregation, Gulf of Bothnia, cystacanth, density, Echinorhynchidae, Echinorhynchus gadi, intermediate host, repeatability, 2, and 59
- Language:
- English
- Description:
- The acanthocephalan Echinorhynchus salmonis Müller, 1784 is a common parasite of salmonid fish, but it has rarely been reported from an intermediate host. Samples of benthic amphipods, Monoporeia affinis (Lindström), were taken from multiple, deep sites (usually below 70 m) in the Gulf of Bothnia over the course of more than a decade and examined for acanthocephalans. Overall, only 0.44% of 23 296 amphipods were infected, all with just a single worm. This prevalence is consistent with several previous reports of acanthocephalans in deep-water, benthic amphipods, but it appears low compared to that often reported for acanthocephalan species infecting littoral amphipods. Parasite occurrence did not exhibit a clear regional pattern (i.e. northern vs southern sites) nor did it have any relationship with site depth. At sites sampled over multiple years, parasite abundance was consistently low (mostly < 0.01), though two spikes in abundance (over 0.06) were also observed, indicating that infection can be substantially higher at particular times or in particular places. The median density of E. salmonis in samples containing the parasite was estimated as 8.4 cystacanths per m2., Daniel P. Benesh, Raija-Liisa Aura, Ann-Britt Andersin, E. Tellervo Valtonen., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public