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21. Seasonal occurrence and microhabitat specificity of Paradiplozoon ichthyoxanthon Avenant-Oldewage in Avenant-Oldewage et al., 2014 (Monogenea: Diplozoidae) infecting Labeobarbus aeneus (Burchell) (Teleostei: Cyprinidae) from the Vaal Dam, South Africa: water quality and host size as determining factors?

Creator:
Gilbert, Beric M and Avenant-Oldewage, Annemariè
Format:
print, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
ekologie, epidemiologie, ecology, epidemiology, Afrika jižní, Africa, Southern, ectoparasite, seasonality, smallmouth yellowfish, gill arch, 2, and 59
Language:
English
Description:
This is the first study detailing the microhabitat specificity of the monogenean parasite, Paradiplozoon ichthyoxanthon Avenant-Oldewage in Avenant-Oldewage et al., 2014. Samples of the monogenean were collected from the gills of the smallmouth yellowfish Labeobarbus aeneus (Burchell) from the Vaal Dam, South Africa, over four seasons with the use of gill nets. Host condition factor fluctuated between the different seasons, with the highest values recorded in summer. Adults and diporpas of P. ichthyoxanthon were found in all four seasons. Adult parasites predominantly infect the first gill arch, whereas diporpas were found on the second and fourth arches. In utero eggs were also found throughout the sampling seasons and their number negatively correlated with the condition factor of the host. The occurrence of adults and diporpas of P. ichthyoxanthon correlated with the size of the host but not the condition factor. Water quality of the study site also had little correlational relationship with the occurrence of the parasites and fluctuations were related to season. The main factor that may drive the microhabitat specificity of P. ichthyoxanthon is the flow of water over the surfaces of the gills and chances of the parasites becoming dislodged. Size of the attachment organs has also been shown to play a role in this specificity, because smaller attachment structures favour stronger holdfast to areas where flow might be stronger compared to larger attachment structures., Beric M. Gilbert, Annemariè Avenant-Oldewage., and Obsahuje bibliografii
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22. Some fixed point theorems in logarithmic convex structures

Creator:
Moazzen, Alireza, Cho, Yoel-Je, Park, Choonkil, and Eshaghi Gordji, Madjid
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
fixed point, logarithmic convex structure, and convex metric space
Language:
English
Description:
In this paper, we introduce the concept of a logarithmic convex structure. Let X be a set and D : X × X → [1, ∞) a function satisfying the following conditions: (i) For all x, y ∈ X, D(x, y) ≥ 1 and D(x, y) = 1 if and only if x = y. (ii) For all x, y ∈ X, D(x, y) = D(y, x). (iii) For all x, y, z ∈ X, D(x, y) ≤ D(x, z)D(z, y). (iv) For all x, y, z ∈ X, z ≠ x, y and λ ∈ (0, 1), D(z, W(x, y, λ)) ≤ D λ (x, z)D 1−λ (y, z), D(x, y) = D(x, W(x, y, λ))D(y, W(x, y, λ)), where W : X ×X ×[0, 1] → X is a continuous mapping. We name this the logarithmic convex structure. In this work we prove some fixed point theorems in the logarithmic convex structure.
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23. The occurrence of metacercariae of Petasiger (Digenea: Echinostomatidae) in an unusual site, within the lateral line scales of cyprinid fishes

Creator:
Kálmán Molnár, Gibson, David I, Cech, Gábor, Papp, Melitta, Deák-Paulus, Petra, Juhász, Lajos, Tóth, Norbert, and Székely, Csaba
Format:
electronic, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
kaprovití, Cyprinidae, Balaton (Maďarsko : jezero), Balaton Lake (Hungary), metacercaria, molecular identification, Kis-Balaton Reservoir, 2, and 59
Language:
English
Description:
During a regular veterinary inspection of fishes from Lake Balaton, Hungary, echinostomatid metacercariae (Digenea), with collar spines characteristic of species of the genera Petasiger Dietz, 1909 and Paryphostomum Dietz, 1909, were found in the lateral line scales of a roach Rutilus rutilus (Linnaeus), an apparently unique site. In a subsequent examination of 586 fishes from 20 different species, similar infections were found in 11 species. The infection was virtually restricted to the lateral line scales, other scales being infected only incidentally. These encysted metacercariae had 27 collar spines, including eight larger angle spines and 19 smaller dorsal spines arranged in two rows. Two types of metacercarial cyst were found. One type had a cyst diameter of 138-171 µm × 105-120 µm and three central dorsal spines that were larger than the remainder and tended to resemble the angle spines. The second type of metacercarial cyst had a diameter of 128-157 µm × 105-115 µm and all 19 dorsal spines of the metacercaria were of a similar size. ITS sequences of the second type of metacercaria exhibited a 100% similarity to sequences of two adult Petasiger phalacrocoracis (Yamaguti, 1939) specimens collected from the gut of Phalacrocorax carbo (Linnaeus) in Hungary and to P. phalacrocoracis deposited in the GenBank database. Sequences obtained from two metacercariae of the first type showed a 2.8-2.9 % difference from sequences of the second type of metacercaria and from those of adult specimens of P. phalacrocoracis from cormorants. Based on these results, the second type metacercaria is considered to be a larval stage of P. phalacrocoracis, but the identity of the first type is uncertain. The unusual location of these metacercariae in the lateral line scales is discussed in relation to their transmission., Kálmán Molnár, David I. Gibson, Gábor Cech, Melitta Papp, Petra Deák-Paulus, Lajos Juhász, Norbert Tóth, Csaba Székely., and Obsahuje bibliografii
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24. The taxonomic identity and phylogenetic relationships of Cercaria pugnax and C. helvetica XII (Digenea: Lecithodendriidae) based on morphological and molecular data

Creator:
Kudlai, Olena, Stunžėnas, Virmantas, and Tkach, Vasyl
Format:
electronic, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
morfologie (biologie), fylogeneze, morphology (biology), phylogeny, Paralecithodendrium, Lecithodendrium, xiphidiocercaria, rDNA sequences, 2, and 59
Language:
English
Description:
The present study analysed the taxonomic status and phylogenetic relationships of two species of xiphidiocercariae of the ʻmicrocotylaeʼ group, Cercaria pugnax La Valette St. George, 1855, from Viviparus viviparus (Linnaeus) in the Ukraine and Cercaria helvetica XII Dubois, 1928 from Bithynia tentaculata (Linnaeus) in Lithuania. Molecular phylogenetic analyses based on sequences of the ITS2 region and partial 28S gene of the nuclear rDNA revealed that both these xiphidiocercariae belong to the Lecithodendriidae Lühe, 1901 and represent larval stages of lecithodendriids parasitic in bats. Cercaria helvetica XII clustered with the typical representatives of the genus Lecithodendrium Looss, 1896, being very close, but not identical, to Lecithodendrium linstowi Dollfus, 1931. Sequences of C. pugnax matched exactly the sequences of adult Paralecithodendrium chilostomum (Mehlis, 1831). Morphological descriptions of the cercariae are included; these represent the first report of non-virgulate xiphidiocercariae belonging to the family Lecithodendriidae. Until now, the presence of glandular virgula organ in the region of the oral sucker was considered a robust synapomorphy for the Lecithodendriidae and several closely related families. Our results have shown that the relative importance of this character is in need of a re-assessment., Olena Kudlai, Virmantas Stunžėnas, Vasyl Tkach., and Obsahuje bibliografii
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25. Two new species of Urocleidoides Mizelle et Price, 1964 (Monogenoidea) from the gill lamellae of profundulids and poeciliids from Central America and southern Mexico

Creator:
Mendoza-Franco, Edgar F, Caspeta-Mandujano, Juan Manuel, Salgado-Maldonado, Guillermo, and Matamoros, Wilfredo Antonio
Format:
electronic, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
parazitologie, parasitology, Guerrero (Mexiko : stát), Oaxaca de Juárez (Mexiko), Chiapas (Mexiko : stát), Guatemala, Honduras, Salvador, Panama, Guerrero (Mexico : state), Oaxaca (Mexico : State), Chiapas (Mexico : state), Guatemala City (Guatemala), Salvador (Brazil), Panama (Panama), Dactylogyridae, Profundulus, Pseudoxiphophorus, Poeciliopsis, Xiphophorus, 2, and 59
Language:
English
Description:
During investigations of gill ectoparasites (Platyhelminthes) parasitising freshwater fish from Central America (Guatemala, Honduras, El Salvador and Panama) and southeastern Mexico (Guerrero, Oaxaca and Chiapas), the following dactylogyrid monogenoidean were found: Urocleidoides simonae sp. n. from Profundulus punctatus (Günther) (type host), Profundulus balsanus Ahl, Profundulus guatemalensis (Günther), Profundulus kreiseri Matamoros, Shaefer, Hernández et Chakrabarty, Profundulus labialis (Günther), Profundulus oaxacae (Meek), Profundulus sp. 1 and Profundulus sp. 2 (all Profundulidae); Urocleidoides vaginoclaustroides sp. n. from Pseudoxiphophorus bimaculata (Heckel) (type host) and Poeciliopsis retropinna (Regan) (both Poeciliidae); and Urocleidoides vaginoclaustrum Jogunoori, Kritsky et Venkatanarasaiah, 2004 from P. labialis, Profundulus portillorum Matamoros et Shaefer and Xiphophorus hellerii Heckel (Poeciliidae). Urocleidoides simonae sp. n. differs from all other congeneric species in having anchors with well-differentiated roots, curved elongate shaft and short point. Urocleidoides vaginoclaustroides sp. n. most closely resembles U. vaginoclaustrum, but differs from this species mainly in the shape of its anchors (i.e. evenly curved shaft and short point vs curved shaft and elongate point extending just past the tip of the superficial anchor root). The complexity of potential hosts for species of Urocleidoides and their effect on its distribution on profundulid and poeciliid fishes are briefly discussed., Edgar F. Mendoza-Franco, Juan Manuel Caspeta-Mandujano, Guillermo Salgado-Maldonado, Wilfredo Antonio Matamoros., and Obsahuje bibliografii
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26. Ultrastructure and phylogeny of Glugea nagelia sp. n. (Microsporidia: Glugeidae), infecting the intestinal wall of the yellowfin hind, Cephalopholis hemistiktos (Actinopterygii: Serranidae), from the Red Sea

Creator:
Abdel-Baki, Abdel-Azeem S, Al-Quraishy, Saleh, Rocha, Sónia, Dkhil, Mohamed A, Casal, Graça, and Azevedo, Carlos
Format:
electronic, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
parazitické organismy, parasitic organisms, fish parasite, microsporidian, fine structure, rRNA genes, 2, and 59
Language:
English
Description:
A new microsporidian species of the genus Glugea Thélohan, 1891 parasitising the marine teleost fish Cephalopholis hemistiktos Rüppell, collected from the Red Sea in Saudi Arabia, is described on the basis of microscopic and molecular procedures. Spherical and whitish xenoma were observed adhering to the intestinal wall. The numerous spores contained within these xenoma, were ovoid to pyriform and measured 4.3-6.0 µm (5.1 µm) in length and 1.8-2.9 µm (2.2 µm) in width. The spore's wall was composed of two thick layers, which were thinner in the area contacting the anchoring disk. The latter appeared at the spore's anterior pole, in an eccentric position to the longitudinal axis. A lamellar polaroplast surrounded the uncoiled portion of the polar filament projected to the basal region of the spore, giving rise to 26-29 turns with winding from the base to the anterior zone of the spore. The posterior vacuole, located at the spore's posterior pole, and surrounded by the polar filament coils, was irregular and composed of light material. Molecular analysis of the rRNA genes, including the ITS region, was performed using maximum parsimony, neighbour-joining and maximum likelihood methods. The ultrastructural features observed, combined with the phylogenetic data analysed, suggest this parasite to be a new species of the genus Glugea. This is the first species of this genus to be reported from Saudi Arabia and is herein named Glugea nagelia sp. n., Abdel-Azeem S. Abdel-Baki, Saleh Al-Quraishy, Sónia Rocha, Mohamed A. Dkhil, Graça Casal, Carlos Azevedo., and Obsahuje bibliografii
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27. Wing morphometric variability of the malaria vector Anopheles (Cellia) epiroticus Linton et Harbach (Diptera: Culicidae) for the duration of the rainy season in coastal areas of Samut Songkhram, Thailand

Creator:
Chaiphongpachara, Tanawat and Laojun, Sedthapong
Format:
print, počítač, and online zdroj
Type:
model:article and TEXT
Subject:
mikroevoluce, microevolution, Thajsko, Thailand, Mosquito, coastal environment, morphological variability, geometric morphometrics, 2, and 59
Language:
English
Description:
In Thailand, Anopheles (Cellia) epiroticus Linton et Harbach (Diptera: Culicidae) is the secondary vector of human malaria along coastal regions. While there are some studies of phenotypic variability and population structure of A. epiroticus, more information on morphological variation would enhance epidemiological understanding of medically important mosquito vectors. This research examined morphological variation at three different distances from coastlines of Samut Songkhram Province, Thailand, using landmark-based geometric morphometrics. Wing shape of A. epiroticus was significantly different in the area 0.2 km away from the sea compared to areas 2 and 4 km away from the sea (p < 0.05). Phenotypic variability in wing shape is associated with distance from the sea. Morphological variations in the area closest to the sea were most pronounced, showing a relationship between A. epiroticus and the ecosystem that affects wing geometry. These results provide important information to understand morphological variation of A. epiroticus in coastal areas., Tanawat Chaiphongpachara and Sedthapong Laojun., and Obsahuje bibliografii
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