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2. A new nematode, Dichelyne alatae sp. n. (Cucullanidae), from Sillaginopsis panijus (Pisces) of West Bengal, India
- Creator:
- De, N. C. and Maity, R. N.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Dichelyne, Nematoda, Sillaginopsis panijus, and India
- Language:
- English
- Description:
- A new nematode, Dichelyne alatae sp. n., is described on the basis of the worms recovered from the intestine of the whiting, Sillaginopsis panijus (Perciformes: Sillaginidae) from the estuary of the river Hooghly at Kalyani, West Bengal, India. Dichelyne alatae differs from congeners in having a small body size, deirids posterior to the oesophagus, short and wide caudal alae at the level of cloacal opening, unequal, alate spicules, a shield-shaped gubemaculum, a different number of caudal papillae and a conical tail with spines in its distal region.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. A synthesis of our current knowledge of philometrid nematodes, a group of increasingly important fish parasites
- Creator:
- Moravec, František and de Buron, Isaure
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Nematoda, Philometridae, parasites, fish, taxonomy, morphology, biology, and pathology
- Language:
- English
- Description:
- Members of the Philometridae represent the most important group of dracunculoid nematodes parasitizing fishes. In his monograph treating the Dracunculoidea, Moravec (2006) reported a total of 11 genera and 105 species of philometrids parasitizing freshwater, brackish-water and marine fishes. However, during the last six years (2007-2012), an additional 42 new species of Philometridae have been described, representing a 40% increase of the number of nominal species. Most of these species (30) belong to Philometra Costa, 1845, mainly represented by parasites of marine fishes, a few others (8) to Philometroides Yamaguti, 1935, and a single one to each of the following genera: Caranginema Moravec, Montoya-Mendoza et Salgado-Maldonado, 2008, Dentiphilometra Moravec et Wang, 2002, Dentirumai Quiazon et Moravec, 2013* and Spirophilometra Parukhin, 1971. Moreover, three new genera, Afrophilometra Moravec, Charo-Karisa et Jirků, 2009, Caranginema and Dentirumai, were erected. Representatives of seven genera, Afrophilometra, Buckleyella Rasheed, 1963, Caranginema, Dentiphilometra, Dentirumai, Paraphilometroides Moravec et Shaharom-Harrison, 1989 and Rumai Travassos, 1960, were studied using scanning electron microscopy (SEM) for the first time. Thirteen known but poorly described philometrid species were redescribed and, in some species of Caranginema and Philometra, previously unknown conspecific males were discovered and described. The male surface ultrastructure studied by SEM provided new taxonomically important features for species distinction. Gene sequencing was used in several recent studies and advanced our understanding of phylogenetic interrelationships among representatives of seven genera (Afrophilometra, Alinema Rasheed, 1963, Caranginema, Nilonema Khalil, 1960, Philometra, Philometroides and Rumai) and of the extent of the biodiversity of philometrids. New data were obtained on the biology and pathogenicity of several species of Nilonema, Philometra, Philometroides and Rumai. The need to carry out surveys in order to find males and to use SEM and gene sequencing to identify philometrids is emphasized. Appropriate quantitative methods to determine the impact of philometrids in ovarian tissue on host fecundity are recommended. Further detailed studies on philometrids would be significant not only from the theoretical viewpoint, but also because of their practical implications. A list of philometrid nematode species by continents is provided.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. An annotated list of parasites (Isopoda, Copepoda, Monogenea, Digenea, Cestoda and Nematoda) collected in groupers (Serranidae, Epinephelinae) in New Caledonia emphasizes parasite biodiversity in coral reef fish
- Creator:
- Justine, Jean-Lou, Beveridge, Ian, Boxshall, Geoffrey A., Bray, Rod A., Moravec, František, Trilles, Jean-Paul, and Whittington, Ian D.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Isopoda, Copepoda, Monogenea, Digenea, Cestoda, Nematoda, Serranidae, Epinephelinae, parasite biodiversity, coral reef, and New Caledonia
- Language:
- English
- Description:
- Over a 7-year period, parasites have been collected from 28 species of groupers (Serranidae, Epinephelinae) in the waters off New Caledonia. Host-parasite and parasite-host lists are provided, with a total of 337 host-parasite combinations, including 146 parasite identifications at the species level. Results are included for isopods (5 species), copepods (19), monogeneans (56), digeneans (28), cestodes (12), and nematodes (12). When results are restricted to those 14 fish species for which more than five specimens were examined and to parasites identified at the species level, 109 host-parasite combinations were recorded, with 63 different species, of which monogeneans account for half (32 species), and an average of 4.5 parasite species per fish species. Digenean records were compared for 16 fish species shared with the study of Cribb et al. (2002); based on a total of 90 parasite records identified at the species level, New Caledonia has 17 new records and only seven species were already known from other locations. We hypothesize that the present results represent only a small part of the actual biodiversity, and we predict a biodiversity of 10 different parasite species and 30 host-parasite combinations per serranid. A comparison with a study on Heron Island (Queensland, Australia) by Lester and Sewell (1989) was attempted: of the four species of fish in common and in a total of 91 host-parasite combinations, only six parasites identified at the species level were shared. This suggests strongly that insufficient sampling impairs proper biogeographical or ecological comparisons. Probably only 3% of the parasite species of coral reef fish are already known in New Caledonia.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. AnguilUcola crassus and A. globiceps (Nematoda: Dracunculoidea) parasitic in the swimbladder of eels (Anguilla japonica and A. anguilla) in East Asia: a review
- Creator:
- Nagasawa, K., Kim, Y.-G., and Hirose, H.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Nematoda, Anguillicola crassus, Anguillicola globiceps, Anguilla japonica, Anguilla anguilla, eels, and V
- Language:
- English
- Description:
- This review compiles information on the taxonomy, identification, geographical distribution, life cycles, host ranges, occurrence, development and growth in both intermediate and final hosts, pathogenicity, and control measures of AnguilUcola crassus and A. globiceps, swimbladder nematodes of farmed and wild populations of two species of eels, Anguilla japonica and A. anguilla, in East Asia. Anguillicola crassus is distributed in Japan, Korea, Taiwan, and China, while A. globiceps is reported only in Japan and China. These nematodes use cyclopoid copepods as intermediate hosts. Known intermediate hosts are Eucyclops serrulatus (Japan) and Therirwcyclops hyalinus (Korea) for A. crassus, and Mesocyclops leuckarti, T. hyalinus, T. taihokuensis, E. serrulatus, Acanthocyclops viridis, and Cyclops slrenuus (China) for A. globiceps. Anguillicola crassus shows a seasonal occurrence in T. hyalinus with high prevalence in summer, Paratenic hosts are yet unknown in East Asia. Anguillicola crassus is relatively common in farmed and wild populations of Anguilla japonica in East Asia, but A. globiceps is usually found in wild populations of A. japonica in Japan and China. In culture ponds, A. crassus is more prevalent and abundant in A. anguilla than in A. japonica. Although A. globiceps induces only the thickening of the host’s swimbladder wall, A. crassus gives severe pathological effects in A. anguilla and heavy infection leads to host mortality. Prevalence of A. crassus in A. japonica cultured in Japan and Korea is relatively low in winter, whereas prevalence of A. globiceps in wild populations of A. japonica from Japan is high in winter.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. Bacillary band ultrastructure of the fish parasite Capillaria pterophylli (Nematoda: Capillariidae)
- Creator:
- Žďárská, Zdeňka and Nebesářová, Jana
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Nematoda, ultrastructure, bacillary band, and Capillaria pterophylli
- Language:
- English
- Description:
- In Capillaria pterophylli Heinze, 1933, two lateral bacillary bands extend along the whole body in female and male worms. A ventral bacillary band is present in females only. The bacillary bands consist of glandular and non-glandular cells, and in the region between the nerve ring and the end of the sticliosome, ciliated sense receptors in tight connection with gland cells are present.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7. Cryopreservation of roe deer abomasal nematodes for morphological identification
- Creator:
- Beraldo, Paola and Pascotto, Ernesto
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Nematoda, Trichostrongyloidea, glycerol, preservation, taxonomy, and morphology
- Language:
- English
- Description:
- Conventional methods to preserve adult nematodes for taxonomic purposes involve the use of fixative or clearing solutions (alcohol, formaldehyde, AFA and lactophenol), which cause morphological alterations and are toxic. The aim of this study is to propose an alternative method based on glycerol-cryopreservation of nematodes for their subsequent identification. Adults of trichostrongylid nematodes from the abomasum of roe deer (Capreolus capreolus Linnaeus) were glycerol-cryopreserved and compared with those fixed in formaldehyde, fresh and frozen without cryoprotectans. Morphology, transparency and elasticity of the anterior and posterior portion of male nematodes were compared, especially the caudal cuticular bursa and genital accessories. The method presented is quick and easy to use, and the quality of nematode specimens is better than that of nematodes fixed by previously used fixatives. Moreover, glycerol cryopreserved nematodes can be stored for a long time at -20°C in perfect condition and they could be suitable for further analyses, such as histological or ultrastructural examinations.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8. Data on the morphology of Viguiera dicrurusi Gupta, 1960 (Nematoda: Habronematidae) with notes on related forms
- Creator:
- Nandi, Anadi P.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Nematoda, morphology, SEM, Viguiera dicrurusi, and Viguiera viduae
- Language:
- English
- Description:
- Morphology of the nematode Viguiera dicrurusi Gupta, 1960 harboured by Dicrurus macrocercus albirictus (Hodgson) (Passseriformes: Dicruridae) from Baruipara in 24-Pargonas (South) district, West Bengal, India was studied by light and scanning electron microscopy (SEM). This represents the first study of V. dicrurusi using SEM. Scanning electron micrographs provided detailed information about the nature of pseudolabial plates, number and shape of teeth, dentate nature of striae, and the relative position of vulva, anus and phasmid opening in female. A detailed morphometrical comparison of this species with Viguiera viduae Chabaud, 1960 described from Dicrurus forficatus from Madagascar indicates that V. viduae is a junior synonym of V. dicrurusi. Two other species, Viguiera bhujangai Jehan, 1972 and Viguiera adsimilisai Sood et Kalia, 1978 are considered species inquirendae.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9. Description of Skrjabinodon alcaraziensis sp. n, (Nematoda: Pharyngodonidae), a parasite of Algyroides marchi (Sauria: Lacertidae)
- Creator:
- Lafuente, M. and Roca, V.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Nematoda, Skrjabinodon, Lacertidae, Algyroides, and Spain
- Language:
- English
- Description:
- Skrjabinodon alcaraziensis sp. n. (Nematoda: Pharyngodonidae) is described from the cloaca of Algyroides marchi Vaiverde, 1958 (Sauria: Lacertidae) from the Alcaraz Mountains (SE Iberian Peninsula). This nematode is characterized by the presence of an unpaired postcloacal papilla in the males, the presence of cuticular spines in the tail of the female and the absence of polar plugs in the eggs.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10. Desiccation stress and recovery in the anhydrobiotic nematode Ditylenchus dipsaci (Nematoda: Anguinidae)
- Creator:
- Wharton, David A. and Aalders, Otto
- Type:
- article, model:article, and TEXT
- Subject:
- Nematoda, Ditylenchus dipsaci, anhydrobiosis, cryptobiosis, lag phase, desiccation, and recovery
- Language:
- English
- Description:
- The plant-parasitic nematode Ditylenchus dipsaci shows a delay in recovery following a period of desiccation and reimmersion in water. This delay, called the \"lag phase\", has been shown to be related to the severity of desiccation. It is the severity of the desiccation stress during dehydration, rather than the final relative humidity to which the animal is exposed which determines the length of the lag phase. A lag phase appears even after a brief exposure to desiccation. These results indicate that a period of repair, or the restoration of a normal physiological state, must be undertaken before activity can resume.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public