Parasites in rotifers from the Volga delta

Internal parasites were recorded in more than 20 species of rotifers from water bodies of the Volga delta. The most abundant species, Asplanchna priodonta Gosse and Brachionus calyciflorus Pallas, were infested every year. The infestation was usually recorded in May and June during the spring-summer maximum in abundance. B. calyciflorus was usually infested by Microsporidium asperospora (Fritsch, 1895), while A. priodonta was more often infested by Pythium sp. and bacteria. At times, the incidence of infestation was as high as 20–40%. The main developmental stages of some parasites were examined and photographed on living material.     

Molecular characteristics of Camallanus Spp. (Spirurida: Camallanidae) in fishes from China based on its rDNA sequences

In the paper, we explored the intra- and interspecific evolutionary variation among species of Camallanus collected from different fish species in various regions of China. We determined the internal transcribed spacers of ribosomal DNA (ITS rDNA) sequences of these nematodes. The divergence (uncorrected p-distance) of ITS1, ITS2, and ITS rDNA data sets confirmed 2 valid species of Camallanus in China, i.e., C. cotti and C. hypophthalmichthys. The 2 species were distinguished not only by their different morphologies and host ranges but also by a tetranucleotide microsatellite (TTGC)n present in the ITS1 region of C. cotti. Phylogenetic analyses of the nematodes disclosed 2 main clades, corresponding to different individuals of C. cotti and C. hypophthalmichthys from different fish species in various geographical locations, although the interior nodes of each clade received poor support.     

Taxonomic diversity of parasites in agnathans and fishes from the Volga River basin v. Nematoda and Gordiacea

The checklist of Nematoda and Gordiacea parasitizing agnathans and fishes in the Volga River basin is presented. Hosts and areas of distribution are indicated for each parasite species. The checklist includes 39 species and 11 nonidentified larval forms of nematodes from 51 fish species. Larvae of Gordius sp. are found in 5 fish species. The nemadote species Sinoichthyonema amuri have been introduced into the Volga basin occasionally during the process on introduction of fish species from Amur River.     

Molecular Genetic Diagnostics of Some Daphnia Species (Crustacea,Cladocera) from the Volga River

Population genetic structure of the widespread Daphnia species from Kuibyshev and Saratov reservoirs was examined using RAPD–PCR technique with four mitochondrial DNA (16S rRNA) specific primers. One of the Daphnia clones examined from the Volga region appeared to be conspecific to the North American Daphnia galeata, while another clone was most likely a hybrid between D. galeata and D. cucullata.     

Some ascaridoid nematodes of fishes: Heterocheilinae

Ascaridoid nematode species reported from fishes and relegated to genera listed by Sprent (1983) within the Heterocheilinae are reviewed. The following species are considered to belong in this category: Dujardinascaris malapteruri (Baylis, 1923) [= D. graberi] from Malapterurus electricus, and possibly Mormyrops engystoma, in Africa; Brevimulticaecum regoi n. sp. from Potamotrygon motoro in South America; Brevimulticaecum heterotis (Petter, Vassiliadès & Marchand, 1979) from Heterotis niloticus in Africa; Brevimulticaecum scleropagi Khalil, 1984 from Scleropages leichardti and S. jardini in Papua New Guinea and Australia. The view is expressed that these heterocheiline species are secondarily derived from related species in crocodilians. It is proposed that Gedoelstascaris Sprent, 1978 is a synonym of Brevimulticaecum Mosgovoy, in Skrjabin et al., 1952 and two new combinations are proposed: Brevimulticaecum vandenbrandeni (Baylis, 1929) and Brevimulticaecum australiensis (Baylis, 1931).     

Taxonomic diversity of parasites in agnathans and fishes from the Volga River basin. VI. Acanthocephala, Hirudinea and Bivalvia

The checklist of Acanthocephala, Hirudinea, and Bivalvia parasitizing agnathans and fishes in the Volga River basin is presented. Hosts and areas of distribution are indicated for each parasites species. The checklist includes 10 species of acanthocephalans, 7 species of leeches, and 9 species of Bivalvia (at the glochidium stage) from 45 fish species. None of the given parasite species is alien for the Volga River basin.     

A new species of Hedruris (Nematoda: Spirurida) from the skink Leiolopisma smithi

Hedruris minuta n. sp. is described from the stomach of Leiolopisma smithi (Gray, 1845), a skink from New Zealand. The new species is distinguished from other species of Hedruris by its small body size, the size and shape of its spicules, and the number of caudal papillae.     

Larval nematodes (Ascarops sp., Spirurida, Spirocercidae) in liver granulomata of the western fence lizard, Sceloporus occidentalis (Iguanidae)

Prevalence of larval nematodes (Ascarops sp., Spirurida, Spirocercidae) and associated granulomata are reported from livers of wild populations of the western fence lizard, Sceloporus occidentalis. Granulomata were circumscribed by layers of fibrocytes. The encysted nematode was surrounded by masses of histiocytes, cellular debris and cells with pyknotic nuclei.     

A checklist of parasitic nematodes from marine fishes of China

A checklist of the parasitic nematodes of Chinese marine fishes is presented. This fauna comprises 90 species, representing 31 genera, 13 families, nine superfamilies, three orders and two subclasses. Additional details for each species include the hosts, localities and references which represent the source of these data.     

Gnathostoma binucleatum (Spirurida: Gnathostomatidae) from the freshwater fish in Tabasco, Mexico

Human gnathostomiasis is a food-born parasitic disease of relative importance in many countries in Southeast Asia. It is caused by several species of nematodes of the genus Gnathostoma. In Mexico is an emerging public health problem since 1970, when first cases were reported. Until today, larval morphometric characters that have been proposed to differentiate between the three species of Gnathostoma present in this country, are not satisfactory. Recently, the presence of advanced third-stage larvae AdvL3 (infective form for humans) in freshwater fishes from Pantanos de Centla, Tabasco. was recorded but their specific identity was not clarified . Examination of four species of freshwater fishes from the same locality revealed that three of them: Petenia splendida (n=58), Cichlasoma managuense (n=35) and Gobiomorus dormitor (n=9) were infected by 15 AdvL3 of Gnathostoma binucleatum. Specific identity was obtained comparing the internal transcribed spacer 2 (ITS2) of the ribosomal DNA with sequences reported in Genbank. This is the first record of G. binucleatum in P. splendida and G. dormitor from Tabasco and the first specific determination of the parasite in the locality.     

Caspian Anadromous Shad Alosa kessleri kessleri (Grimm, 1887) from the Akhtuba River,Lower Volga River Basin: Biological and Morphological Features

Data on the dynamics of anadromous migration, age composition, body length, body weight, and morphometric characteristics of Caspian anadromous shad from the Akhtuba River are presented. Currently, Caspian anadromous shad from the Akhtuba River is monomorphic; no temporal groups have been identified. The population is represented by medium-sized young early-maturing (age of 2–3 years) fish with life longevity less than 5 years. Generally, according to the most important diagnostic signs, first and foremost, to the number of gill stamens and some plastic signs, Caspian anadromous shad from the Akhtuba River falls within the range of the diversity that is typical for the form.     

The species composition and ecological characteristics of trematodes from reptiles in the Volga delta

In the result of parasitological researches of reptiles of the Volga delta, 17 species of trematodes belonging to 10 families and 5 orders have been recovered. The dynamics of trematodes in reptiles is regulated by transformations of biocenoses of the delta depending on fluctuations of the Caspian sea level.     

Monogenea of the fishes from Chu River basin

Results of the long-term faunistic study of Monogenea from fishes of the Chu River basin are reported. Fauna of Monogenea in the studied area was found to include 51 species of 11 genera and 5 families. Thirteen parasite species occurred in the mountain part of the basin, and 40 species inhabit the valley zone, including 10 species of the Amur faunistic complex probably introduced to Kyrgyzstan together with acclimatized fishes.     

Metazoan parasites of fishes from the Bug River

Results if the ichthyoparasitological investigation of the Bug River carried out in 1996-1999 are reported. Twenty-nine metazoan parasite species from 7 classes were found in fishes from the studied area, with the total infestation rate 63.9%. Thirteen of them parasitize fish at larval stages. Metacercariae of Opisthorchis felineus, which ate the agents of opisthorchosis in man and animals, were found in roach.     

Parasites taxonomic diversity of agnathans and fishes of Volga River Basin. IV. Amphilinida and Cestoda

The checklist of Amphilinida and Cestoda of fish in the Volga basin is presented with indication of host and distribution in different areas of the basin. The data on cestodes of 51 fish species are given. The checklist includes 40 species of cestodes and 1 species of amphilins. The families Caryophyllaeidae (8 species) and Proteocephalidae (10 species) are the most numerous. Cestodes Bothriocephalus acheilognathi and Khawia sinensis have been introduced into the Volga basin occasionally during the process of Amur fish species introduction.     

Skrjabillanus cyprini n. sp. (Nematoda: Dracunculoidea) from the scales of common carp Cyprinus carpio (Pisces) from Hungary

A new species of the histozoic nematode, Skrjabillanus cyprini n. sp., is described from the subsquamal part of the scales of common carp Cyprinus carpio L. from Lake Balaton, Hungary. It differs from the other three congeneric species mainly in possessing an extremely small, oval-shaped buccal capsule with a large tooth at the bottom, in the shape of the cephalic end (somewhat bulbously inflated, truncated anteriorly), the extent of the oesophageal glands and body size (body length of male and female 1,800–3,000 µm and 3,200–4,100 µm, respectively). A key to the identification of Skrjabillanus spp. is provided.