A revision of Petasiger Dietz, 1909 (Digenea: Echinostomatidae) and a key to its species (original) (raw)
Related papers
Parasite, 1997
The morphology of three Palaearctic species of the genus Petasiger Dietz, 1909, parasitizing grebes and exhibiting a significant degree of overlap, was studied. Ninety-three specimens belonging to P. grandivesicularis, P. neocomense and P. pungens were compared using univariate and multivariate statistical analyses of 17 metrical characters. A stepwise discriminant analysis run in three variants and based on seven variables (body length, body width, oral sucker diameter, pharynx diameter, ventral sucker diameter, posterior testis diameter and oesophagus length) yielded a 100 % accurate classification. The first canonical discriminant function separated specimens belonging to P. grandivesicularis and P. pungens, and the second function effectively differentiated the P. neocomense sample. Two variables (pharynx diameter and oesophagus length] were strongly correlated with the canonical functions and, when used alone, discriminated the three Petasiger spp. A simple key based on two variables used in the discriminant analyses and a table of the qualitative and quantitative characters used for the identification of the three species are presented.
Systematic Parasitology, 1998
A re-examination of three sets of trematodes collected in two species of grebes, Podiceps grisegena and P. auritus, from the Kamchatka region of eastern Russia, previously identified as Petasiger neocomense, revealed that they actually represent a new species, which is named Petasiger oschmarini. Characteristic morphological features of the new species include: a head collar possessing a constant number of 19 spines; a large cirrus-sac comparable in size to the ventral sucker, containing a bipartite seminal vesicle and a well-developed pars prostatica; a large bulb-like cirrus similar in size to the testes; a long forebody; a long oesophagus; testes situated obliquely or symmetrically; and lateral vitelline fields which are not confluent in the forebody. The new species is distinguished from all Palaearctic and Nearctic members of Petasiger which possess 19 collar spines. The material described by as P. neocomense is considered to be conspecific.
Systematic parasitology, 2014
Large-tailed echinostomatid cercariae of the genus Petasiger Dietz, 1909 (Digenea: Echinostomatidae) from the planorbid snails Gyraulus albus (Müller) and Planorbis planorbis (L.) collected in Germany and the Czech Republic and metacercariae from Gasterosteus aculeatus L. (Gasterosteiformes: Gasterosteidae) collected in Canada are characterised morphologically and molecularly. The rediae, cercariae and metacercariae are described in detail and compared with the existing data on the larval stages of Petasiger spp. Comparative molecular analyses using 28S rDNA and nad1 mitochondrial sequences supported the distinct status of four species of Petasiger. Molecular and morphological evidence for their distinction and an updated key to the known large-tailed cercariae of Petasiger from the Palaearctic are provided.
Annals of Agricultural and Environmental Medicine, 2019
Introduction. Radix auricularia (Linnaeus, 1758) is a freshwater gastropod belongs to the Lymnaeidae (pond snails) family which act as intermediate hosts or vectors of various parasitic flukes. No study has yet been undertaken on the prevalence of Petasiger spp. infection in R. auricularia. Species of Petasiger (Dietz, 1909) are a cosmopolitan parasite that utilize snails as the first intermediate host, with vertebrates like amphibians larvae and fish as the second intermediate host, followed by fish-eating birds. The current paper is considered to be the first report of Petasiger exaeretus parasitized R. auricularia in Iraq, which is supported with molecular and phylogenetic analysis. Materials and method. Freshwater snails R. auricularia were collected during October 2016-September 2017 from different locations of Sufaia village on the Greater Zab river, Erbil province, Iraq. Results. A total of 307 freshwater snails R. auricularia were collected, only five of them were infected with a prevalence of Petasiger exaeretus (1.62%). Conclusions. The current study agrees with the opinion of Selbach, Soldánová (26), which suggested the possibility of a much higher morphological diversity within Petasiger species, based on the number of described cercariae, compared with adult forms.It is clear that P. phalacrocoracis specimens have often been erroneously designated as P. exaeretus by many authors (Našincová et al., 1994). Certain morphological similarities and dissimilarities between P. exaeretus and P. phalacrocoracis can be detected: the pear-shaped body resembles P. exaeretus, whereas, P. phalacrocoracis have an elongated body.
Bulletin of Zoological Nomenclature, 2018
The purpose of this application, under Article 75.6 of the Code, is to confirm the availability and to maintain the usage of the genus Petalodus Owen, 1840, which is threatened by the identity of the type specimen of its type species Petalodus hastingsii Owen, 1840. The description and figure of the specimen by Owen (1840) do not match the actual specimen, nor does it resemble the subtriangular crowns traditionally referred to the form taxon Petalodus described and illustrated by Agassiz (1838: 108–109, pl. 19, figs. 11–13) as Chomatodus (subsequently Petalodus acuminatus by Agassiz, 1843: 159, 174, nota). Additional, more complete, specimens from the same bed and locality as Owen's specimen were described and illustrated by Arthur Woodward (1889) as Petalodus acuminatus. The crowns of these teeth are labial-lingually compressed, vertically short, broad-based, subtriangular, and convex labially and concave lingually. In the subsequent 170 years, teeth identified and published as Petalodus have referred to the subtriangular teeth as described by Agassiz and Woodward, and not to the rectangular lamelliform tooth described by Owen. The Commission is therefore asked to exercise its plenary power to set aside the misleading and inadequate holotype, NHMUK PV P613, and designate as neotype specimen NHMUK PV P75414, a more complete tooth that shows all the characteristic features of Petalodus.
A revision of Patagifer Dietz, 1909 (Digenea: Echinostomatidae) and a key to its species
Systematic Parasitology, 2008
Patagifer Dietz, 1909 is revised and a key to the species is presented. P. oweni n. sp. is described from Threskiornis molucca (Cuvier) in the Western Province of Papua New Guinea and distinguished from the related P. chandrapuri Srivastava, 1952 by: the shape of the pair of large angle spines (cudgel-shaped vs sub-rectangular); pointed (vs rod-shaped) marginal spines; a smaller body and internal organs; more anteriorly located testes; and larger eggs. The new species differs from P. brygooi Richard, 1964 in its larger body, head collar, suckers, pharynx and eggs, longer oesophagus and testes, the latter being also more elongate and more anteriorly located, and a different number of collar spines (61-62 vs 59). P. bilobus (Rudolphi, 1819) (the typespecies), P. parvispinosus Yamaguti, 1933, P. chandrapuri and P. vioscai Lumsden, 1962 are redescribed on the basis of museum and newly collected material. The variations in the number and size of the collar spines and other metrical characters of P. bilobus are studied in two different host species from Europe, Plegadis falcinellus and Platalea leucorodia. Other species considered valid are:
Zoological Studies 47(4): 507-518 (2008)
2008
Takahashi (1932) described Singhius as a monotypic subgenus of Dialeurodes Cockerell, and Mound and Halsey (1978) subsequently raised this to genus level, and fixed Aleyrodes hibisci (Kotinsky) as its type species. It is a small genus which currently includes 4 species (Martin and Mound 2007), of which S. hibisci (Kotinsky) is known from Cambodia,