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Camallanus ancylodirus Ward and Magath 1916 is redescribed, based on examination of syntypes. This species differs from C. oxycephalus Ward and Magath 1916, the only other camallanid described from freshwater fishes of North America, in the size of male worms, number and arrangement of caudal papillae in males, shape of the male caudal end, position of the vulva, and length and shape of the female tail. The host range of C. ancylodirus is not clear from literature reports because the species may have been confused with C. oxycephalus.  相似文献   

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We describe a new species of Nomimoscolex from the Amazon siluriform fishes Brachyplatystoma filamentosum, B. flavicans and B. vaillanti. It differs from N. piraeeba in a lower mean number of testes, the paramuscular position of the vitelline follicles, the ovarian width/proglottis width ratio and the cirrus-pouch length/proglottis width ratio. Protein electrophoresis assays performed for 25 enzymatic systems showed that specimens of N. suspectus n. sp. from the three host species form a homogenous population which was genetically isolated from N. piraeeba and N. dorad. Moreover, the latter two species, synonymised by Rego (1991) because of their close morphological similarity, could be separated at eight loci. We thus restore N. dorad as a valid species. We finally examined the composition of the genus Nomimoscolex using DNA sequences from the 5.8S rRNA, ITS-2 and 28S rRNA nuclear ribosomal genes and a matrix of 24 morphological characters. Phylogenetic relationships were inferred for nine species of the genus, five members of other monticelliid genera and two outgroup species. The results of the phylogenetic analyses performed on morphological and molecular characters converged with those from allozyme studies and showed that N. suspectus, N. piraeeba and N. dorad clustered in a distinct clade that excluded other members of the genus. We therefore recognised them as an aggregate of species to reflect an isolation supported by both morphological and genetic data. Because relationships among the remaining Nomimoscolex representatives and other genera were generally poorly resolved, regardless of the database analysed, no action was taken to reorganise them into alternative groupings.  相似文献   

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Parachordatortilis n. g. is proposed as a monotypic genus for Parachordatortilis mathevossianae (Petrov & Chertkova, 1950) n. comb. (Spirurida, Acuariidae), previously Dispharynx mathevossianae Petrov & Chertkova, 1950. The new genus can be distinguished from all other acuariid genera by having cordons with a sinistral torsion. Parachordatortilis possesses cordons consisting of two rows of delicate cuticular plates delimiting a longitudinal canal. This pattern of cordon structure suggests that Parachordatortilis is closely related to Dispharynx Railliet, Henry & Sisoff, 1912, Synhimantus Railliet, Henry & Sisoff, 1912 and Chordatortilis Machado de Mendon?a & Olivera de Rodrigues, 1985. P. mathevossianae is redescribed on the basis of light and scanning electron microscopical observations of specimens collected from a common kestrel Falco tinnunculus L. in southern Italy.  相似文献   

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The tapeworm Proteocephalus glanduligerus (Janicki, 1928) Fuhrmann, 1933 (Cestoda: Proteocephalidea), a parasite of clariid catfishes (Clarias spp.) in Africa, is redescribed on the basis of an evaluation of voucher material and newly collected specimens from Clarias gariepinus and C. cf. anguillaris from the Sudan, Ethiopia, and South Africa. The most typical characteristic of P. glanduligerus (previously misspelled as P. glanduligera or P. glanduliger) is the presence of an extremely large glandular apical organ, the size of which is 1.6-3.5 times larger than that of the suckers. In addition, other morphological characteristics unreported in previous accounts are provided, such as an unusual position of osmoregulatory canals (situated close to each other, with the dorsal canal latero-ventral to testes), the presence of a vaginal sphincter, several (usually 3-5) uterine pores, and eggs with paired lateral auricular swellings (extensions) of the outer envelope.  相似文献   

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The cestode Nomimoscolex sudobim Woodland, 1935 (Proteocephalidea) is redescribed on the basis of its type-specimens and recently collected material found in the intestine of the 'sudobim' Pseudoplatystoma fasciatum (Siluriformes: Pimelodidae) (type-host), from the Amazon River (near the type-locality). Nomimoscolex pertierrae n. sp. is described from the 'surubi' Pseudoplatystoma corruscans from the Paraná River around Porto Rico. Among fifteen known Nomimoscolex species, only N. sudobim possess a cortical uterus in combination with osmoregulatory canals some distance internal to the proglottis margins, as in N. pertierrae n. sp. N. pertierrae differs from N. sudobim, which exhibits the most similarity with the former species, in the morphology of the scolex, the size and unusual shape of microtriches (slender digitiform) on the internal and marginal regions of the suckers, and in the lower mean number of testes [(114 in N. pertierrae, ranging between 216 (recently collected material) and 240 (type-material) in N. sudobim)]. The material described as N. sudobim by Pavanelli & Rego (1992) from the intestine of P. corruscans is considered to be N. pertierrae. The utility of microtriches as characters for distinguishing between species is demonstrated in the clear differences in the shape of those of N. pertierrae and N. sudobim. The morphology of microtriches warrants more attention in future studies on the taxonomy of proteocephalidean cestodes.  相似文献   

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Pelecanema n. g. is erected for P. sirry (Khalil, 1931) n. comb., syn. Synhimantus sirry Khalil, 1931 (type-species) and P. pelecani (Johnston & Mawson, 1942) n. comb., syn. Dispharynx pelecani Johnston & Mawson, 1942. In the structure of its cordons, consisting of two rows of delicate cuticular plates, the new genus is similar to Synhimantus Railliet, Henry & Sisoff, 1912, Dispharynx Railliet, Henry & Sisoff, 1912, Chordatortilis Machado de Mendon?a & Olivera de Rodrigues, 1965 and Parachordatortilis Mutafchiev, Santoro & Georgiev, 2010. Pelecanema sirry, a parasite of Pelecanus onocrotalus L. and P. crispus Bruch (Pelecaniformes, Pelecanidae) in Africa (Egypt and Senegal) and Europe (Ukraine and Bulgaria), is redescribed using light and scanning electron microscopy on the basis of specimens from P. crispus from Bulgaria. Pelecanema pelecani, a parasite of Pelecanus conspicillatus Temminck in Australia, is also redescribed using light microscopy on the basis of specimens from its type-host and type-locality. In contrast to a previous opinion recognising Pelecanema sirry and P. pelecani as synonyms, the two species are considered distinct and P. pelecani is validated.  相似文献   

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The phylogenetic relationships and systematic position of the digenean genus Ophiosacculus Macy, 1935 has been controversial and opinions of different authors on its systematic position and content are contradictory. Molecular analysis based on the partial sequences of the large subunit ribosomal DNA gene of the type and only valid species of the genus, Ophiosacculus mehelyi (Mödlinger, 1930), as well as previously published sequences of members of several families of Plagiorchiata (including the Allassogonoporidae, Lecithodendriidae and Pleurogenidae as potential relatives of Ophiosacculus) has shown that Ophiosacculus forms a clade with the typical representatives of the Lecithodendriidae from bats. Ophiosacculus is basal to the cluster containing Lecithodendrium, Prosthodendrium and Pycnoporus and has quite pronounced differences in the sequenced fragment compared to these genera. Based on the results of the molecular study, morphological characteristics of Ophiosacculus (in particular, possession of a seminal vesicle lying freely in parenchyma) and the fact that the type-specimen of Gyrabascus brevigastrus Macy, 1835 (type-species of the monotypic genus Gyrabascus and type-genus of the subfamily Gyrabascinae) belongs to Allassogonoporus, a new subfamily, the Ophiosacculinae, with Ophiosacculus as the type-genus, is established within the Lecithodendriidae. Molecular study did not support a close phylogenetic relationship between Allassogonoporus and Ophiosacculus, although several authors previously allocated both these genera to the Allassogonoporidae. Morphological study revealed the position of the genital pore in O. mehelyi to be at the posterior margin of the ventral sucker. An amended diagnosis of Ophiosacculus and a diagnosis of Ophiosacculinae n. subfam. are given.  相似文献   

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All parasitic stages of Amblyomma boeroi n. sp. (Acari: Ixodidae) are described here from Catagonus wagneri (Rusconi) in Argentina. The diagnostic characters for the male are a combination of orbited eyes, a 2/2 dental formula, coxa IV considerably larger than coxae I–III and with a long, sickle-shaped, medially directed spur arising from its internal margin, a scutum which is light grey to very pale ivory in colour, and the absence of a postanal groove. The diagnostic characters for the females are a combination of orbited eyes, a central pair and two marginal pairs of short, coarse notal setae, a 2/2 dental formula, and the absence of a postanal groove. The nymph has short palpi and a 2/2 dental formula arranged in 6 rows, its eyes are convex and orbited, and it has no postanal groove. The dorsally rectangular basis capituli of the larva, its bulging eyes and slightly sinuous posterior scutal margin all serve to distinguish it from the larva of other species of the genus. The principal host for all parasitic stages is C. wagneri (Artiodactyla: Tayassuidae). Phylogenetically A. boeroi appears to represent an independent lineage within Amblyomma Koch, 1844.  相似文献   

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Cucullanus bioccai n. sp. described from the intestine of Mugil cephalus caught in Lake Sabaudia (Latina, Italy) is compared with C. dodsworthi and C. mugili parasites of mullets. It differs from C. dodsworthi mainly for the position of the 1st pair of precloacal papillae, the position of vulva, the shape of gubernaculum, the measurements of eggs; from C. mugili for the number of papillae, the position of the 1st pair of precloacal papillae, the conformation of cloaca and the position of vulva.  相似文献   

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A new species of an oxyurid nematode is described from the large intestine of the lacertid lizard Podarcis sicula (Rafinesque. 1810) (Reptilia: Lacertidae) from Italy. Spauligodon aloisei n. sp. differs from other species of the genus by a combination of morphological and metrical characters, including a spined tail in males and females, absence of a spicule in males, arrangement of the last pair of the male caudal papillae, vulva location, and egg morphology. The species most similar to S. aloisei n. sp. is Spauligodon caspius Annayev, 1987, described from Tenuidactylus (=Gymnodactylus) caspius in Turkmenistan. Tail length and location of the excretory pore and vulvar opening separate S. caspius from S. aloisei n. sp. This article increases the number of species of this genus from reptiles in the Paleartic Realm to 19.  相似文献   

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Notomegarhynchus n. gen. (Eucestoda: Tetraphyllidea) is proposed to accommodate Notomegarhynchus navonae n. gen., n. sp. from Atlantoraja castelnaui in Mar del Plata, Argentina. Notomegarhynchus shetlandicum n. comb. from Bathyraja eatonii and B. maccaini in South Shetlands region, Antarctica, is a second species in the genus. Notomegarhynchus belongs to the Echeneibothriinae within the Phyllobothriidae. It can be distinguished from all other tetraphyllidean genera by the structure of the scolex in form of a massive myzorhynchus consisting of a proscolex and an apical organ, both of which are nonretractable and noninvaginable; in addition, there are 4 pedunculated and nonloculate acetabula. Notomegarhynchus shetlandicum is differentiated from N. navonae particularly in details of acetabular and myzorhynchus morphology, arrangement of testes, and shape of eggs. The inclusion of Notomegarhynchus in the Echeneibothriinae requires emendation of the diagnosis of the subfamily to include taxa possessing postvaginal testes. In addition, new terminology is proposed for distinct regions of the scolex.  相似文献   

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The species Tejidotaenia appendiculata (Baylis, 1947), a parasite found in teju, Tupinambis teguixin is redescribed and a new diagnosis is provided. The species is characterized by the anterior position of the ovary and the peculiar shape of suckers. It is the first record of this species in Brazil.  相似文献   

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Galaxitaenia n. gen. (Eucestoda: Pseudophyllidea) is proposed to accommodate Galaxitaenia toloi n. gen., n. sp. from Galaxias platei, a freshwater fish inhabiting Andean lakes in Argentine Patagonia. Galaxitaenia belongs to the Triaenophoridae because it possesses a marginal genital pore, a ventral uterine pore, and a follicular vitelline gland. The new genus can be distinguished from other triaenophorids by the following combination of characters: a scolex with a prominent rectangular apical disc without hooks, grooves, or indentations; neck present; segments wider than long to quadrangular; testes in 2 lateral fields, often connected anteriorly; cirrus unarmed; an ovary situated posteriorly; a vagina posterior to the cirrus sac; vitelline follicles medullary, in 2 ventral fields forming 2 wings interrupted medially; a uterus saccate to branched; and eggs without operculum. The types, distribution, and density of microtriches were analyzed on the surface of the tegument of scolex, neck, and immature segments. The presence of tumuli were observed on the apical disc of the scolex. Galaxitaenia toloi n. sp. is the first triaenophorid species recorded in a South American freshwater fish and the fourth helminth parasitizing the intestine of G. platei.  相似文献   

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Two species of the genus Antechiniscus have been found in Nothofagus forests in Australia. The new species A. moscali sp. n. is described. The New Zealand species A. parvisentus (Horning & Schuster, 1983) is redescribed from type material and from the new material from Australia. The taxonomic status of the two species within the genus is discussed.  相似文献   

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