Volume 55, Issue 1

To date, Myxidium elmatboulii Ali, Abdel-Baki et Sakran, 2006 (Myxozoa, Myxosporea) is the only species of the genus known from the Red Sea, and was originally described as a coelozoic parasite in the gall bladder of the belonid fish, Tylosurus choram. A Myxidium sp. closely similar to M. elmatboulii is described herein for the first time as a histozoic parasite in the ovary of the onespot snapper fish, Lutjanus monostigma (Teleostei, Lutjanidae) from the Red Sea coast of Saudi Arabia. The infected ovary was morphologically abnormal, with two protruding digitiform black cysts at its distal end, densely packed with mature plasmodia suspended in a mucoid liquid. Histological examination revealed that the cysts were extended deeply within the ovary, and each was surrounded by a capsule consisting of a relatively thick layer of fibrous connective tissues of host origin (host tissue reaction), and followed internally by a distinct black layer composed of melanomacrophages encircling the parasite mass; this layer clearly indicates the ability of this myxosporean parasite to induce a strong immune inflammatory response in the ovary of L. monostigma. Many small or developing cysts with the same characteristics were seen scattered in the connective tissue between the ovarian follicles. Plasmodia or spores of the parasite were not seen within the oocytes or within its developmental stages. The cysts occupied a considerable part of the ovary, and some areas of the ovarian tissues appeared to be vacuolated or degenerated. Thus, the typical ovarian structure of L. monostigma was greatly affected and lost its normal architecture. Therefore, the infection caused by this Myxidium sp. is presumed to negatively affect the reproductive capacity of the fish host.

The Tc1 transposable element has been found in a wide variety of organisms including vertebrates, insects and fungi but has not been previously reported in Microsporidia. In this study we characterize an intact DNA transposon (NbTc1) from the microsporidian Nosema bombycis. This transposable element encodes a 337 amino acid transposase sequence, which contains the D,D34E functional motif required for transposition. A Southern blot of N. bombycis DNA separated by pulsedesis shows that copies of the NbTc1 transposon are present on 10 of the 14 chromosomes of N. bombycis. Amino acid sequence variation among copies of the NbTc1 is low, suggesting a conserved function for this transposon within N. bombycis. Phylogenetic analysis indicates that NbTc1 is a new member of the Tc1 family lineage, quite distinct from all previously described Tc1 elements, including those from fungi, indicating that NbTc1 forms a unique clade of the Tc1 superfamily. However, the Tc1 transposon is too divergent to resolve the major phylogenetic relationships among these superfamilies. Reverse transcriptase PCR and Solexa sequencing suggest that NbTc1 possesses transcriptional activity. Considering the interest in Microsporidia as biological control agents, the NbTc1 transposon may be a useful vector for the efficient transfection of these important parasites into host species.

Demidospermus paranaensis sp. nov. is described from the gills of Loricariichthys platymetopon Isbrücker et Nijssen (Loricariidae, Siluriformes) from the Upper Paraná River floodplain, Brazil. This new species differs from other members of Demidospermus in the following features: tegument with annulations throughout trunk and peduncle, eyes absent, longer male copulatory organ (MCO) with ovate base. Demidospermus paranaensis sp. nov. is similar to its congenerics by having tandem gonads, a counterclockwise-coiled MCO, non-articulated groove-like accessory piece serving as a MCO guide, sinistral vaginal aperture, and V-shaped haptoral bars.

Novel combinations of mitochondrial DNA (CO1) and internal transcribed spacers of nuclear ribosomal DNA (ITS) were detected among Gyrodactylus parasites on brown trout (Salmo trutta L.), rainbow trout (Oncorhynchus mykiss (Walbaum)), and Ohrid trout (Salmo letnica (Karaman)) from salmonid farms in Poland and Macedonia. Some clones differed from standard ITS only by ≤ 4 nucleotides, but they belonged to a mtDNA clade that differed from the Northern European lineages of G. salaris by d MCL = 0.266 ± 0.108 (maximum composite likelihood distance). The divergence of d MCL = 0.013 ± 0.005 within the alien mtDNA clade suggested introgression from an unknown maternal ancestor into the G. salaris Malmberg genome 137 to 57 kyr ago (or, less probably, repeated introgression). A comparable modern hybrid was detected based on permanently heterozygous ITS (28 bp/1264 = 2.2%) in a clone that is widespread throughout Finnish rainbow trout farms. This was a F1 hybrid of maternal G. pomeraniae Kuusela, Ziętara et Lumme (on roach, Rutilus rutilus (L.)) and G. lavareti Malmberg (on whitefish, Coregonus lavaretus (L.)). The mtDNA of the parental species differed by d MCL = 0.290 ± 0.130. The observations emphasize that both nuclear and maternally-inherited DNA markers are necessary to characterize sexually-produced lineages or clones of Gyrodactylus. The hybridization events demonstrated predict incongruence of mitochondrial vs. nuclear gene trees, i.e., reticulate evolution in species trees.

Seriolella porosa (Silver warehou) is an important fish resource in the Argentine Sea. No previous studies have been carried out to date on its parasite fauna. The present study aims to (i) identify the digenean trematodes that parasitize Silver warehou, (ii) estimate parasite frequency and abundance, and (iii) establish their relationship with fish size and sex. A total of 100 specimens of S. porosa from San Matías Gulf, Argentina were examined between September and October 2006. Host size and sex were determined. Parasites extracted from the stomach lumen were fixed, conserved in 5% formalin, and stained with Langeron’s hydrochloric carmine. The following parameters were also determined: dispersion coefficient, prevalence, intensity, and parasite abundance. Differences in parasitism were assessed using non-parametric tests. Four adult digenean species were found in the stomach, namely Lecithocladium cristatum, Aponurus laguncula, Elytrophalloides oatesi and Gonocerca cf. phycidis. L. cristatum was not only dominant but also the most prevalent and abundant species. None of the digeneans showed interspecific association with each other and therefore they might follow different patterns of colonization (i.e., different intermediate hosts, seasonal and/or spatial distribution of the infective stages). Significant differences were observed among the digeneans analyzed in respect to the sex of the host. Results from this study show that Silver warehou plays a key role as a final host of a significant number of digeneans in the ecosystem. This study is the first step in an attempt to further determine the larval stages in intermediate hosts in San Matías Gulf.

The trematode Echinostephilla patellae is an abundant but scarcely investigated parasite found in coastal ecosystems of the British Isles. Redial and cercarial stages of the digenean occur in the digestive gland and gonads of common limpets Patella vulgata. Here, we present data on the temporal distribution of E. patellae infections in P. vulgata from an intertidal site on the Irish south coast as well as on the intramolluscan development of the cercariae over a period of one year. Prevalence of infection showed temporal variation with a distinct peak in September, possibly related to an increase in the abundance of bird final hosts coinciding with comparatively high temperatures at the study locality during the summer months. Maturation of cercarial stages was strongly correlated with water temperature. Whilst fully developed cercariae were present in the rediae from May to November, large numbers of infective stages occurred in the limpets’ mantle blood vessels — where they accumulate prior to release — between June and September, suggesting this period of time to be the main transmission window for E. patellae cercariae.

Pseudopecoelus sosoae sp. nov. and P. sewelli Bray, 1990 are described from the rare fish Neoscombrops pacificus from the deep-sea (about 200–400 m) off Nouméa, New Caledonia, the southernmost report of this fish species. A visual key based on 12 characters is presented, which shows that P. sosoae is distinguished from the most similar species (P. vulgaris, P. elongatus, P. priacanthi, P. akamachi and P. sphyraenae) by its very large eggs, elongate body and unlobed gonads. P. sewelli has a similar shape, but much smaller eggs and lobed gonads. Abstract Pseudopecoelus sosoae sp. nov. et P. sewelli Bray, 1990 sont décrits du poisson rare Neoscombrops pacificus pêché en mer profonde au large de Nouméa, Nouvelle-Calédonie, la mention la plus au Sud de cette espèce. Une clé visuelle basée sur 12 caractères est présentée, et montre que P. sosoae se distingue par ses oeufs très grands, son corps allongé et ses gonades non lobées. P. sewelli a une forme similaire, mais des oeufs plus petits et des gonades lobées.

Mathevotaenia panamaensis sp. nov. (Cestoda, Anoplocephalidae, Linstowiinae) from a green spiny lizard, Sceloporus malachiticus, collected in Panama is described. This is the first species of Mathevotaenia reported from a lizard host. The new species is most similar to Mathevotaenia bivittata in that mature eggs are concentrated along the lateral margins of the proglottids. Major differences between the two species include oval cirrus sac in M. bivittata, a spherical cirrus sac in M. panamaensis; ovary compact consisting of 10–15 short lobules in M. bivittata, ovary bilobed with each lobe consisting of 3–4 lobules in M. panamaensis.

Spermiogenesis and spermatozoon ultrastructure of the tapeworm Parabothriocephalus gracilis were described using transmission electron microscopy (TEM). Spermiogenesis is characterized by the formation of a zone of differentiation with two centrioles associated with striated rootlets, and an intercentriolar body between them. The two flagella undergo a rotation of 90° until they become parallel to the median cytoplasmic extension with which they fuse. Electron-dense material is present in the apical region of the zone of differentiation in the early stages of spermiogenesis. This electron-dense material is characteristic for the orders Bothriocephalidea and Diphyllobothriidea. The mature spermatozoon contains two axonemes of the 9 + ‘1’ trepaxonematan pattern, nucleus, parallel cortical microtubules and electron-dense granules of glycogen. The anterior extremity of the spermatozoon exhibits a single helical electron-dense crested body 130 nm thick. One of the most interesting features is the presence of a ring of cortical microtubules surrounding the axoneme. This character has been reported only for species of the order Bothriocephalidea and may be unique in this cestode group.

Monodontella giraffae Yorke et Maplestone, 1926 was collected from the biliary duct of liver of a dead giraffe, Giraffa camelopardalis (Linnaeus) from the Tianjin Zoo, Tianjin, China. A redescription of this species was made using light microscopy and scanning electron microscopy (SEM). The lateral alae and the detailed structures of the spicules and genital cone were observed for the first time by SEM. The taxonomic status of the genus is discussed.

Examinations of materials of trichinelloid nematodes recently collected from the digestive tract of marine fishes off New Caledonia, South Pacific, revealed the presence of several species of the families Capillariidae and Trichosomoididae, including capillariids Pseudocapillaria novaecaledoniensis sp. nov. from the deep-sea Pristipomoides argyrogrammicus (Valenciennes) (Lutjanidae) and Pseudocapillaria echenei (Parukhin, 1967) from Echeneis naucrates Linnaeus (Echeneidae), and the trichosomoidid Huffmanela sp. (female) from Bodianus perditio (Quoy et Gaimard) (Labridae). P. novaecaledoniensis is characterized mainly by the structure and length (318–321 µm) of spicule and the presence of a dorsal cuticular membrane interconnecting both ventrolateral caudal lobes in the male (subgenus Ichthyocapillaria Moravec, 1982). The previously poorly known P. echenei is redescribed and recorded for the first time from the South Pacific Ocean. In addition, five morphologically different types of capillariid females without generic identification, designated as Capillariidae gen. spp. 1–5, each of them probably representing a new species, were recorded from Fistularia commersonii Rüppell (Fistulariidae), Synodus dermatogenys Fowler (Synodontidae), Carangoides oblongus (Cuvier) (Carangidae), Diagramma pictum (Thunberg) (Haemulidae) and Stegostoma fasciatum (Hermann) (Stegostomidae), respectively. Capillaria decapteri is transferred to Pseudocapillaria Mendonça, 1963 as P. decapteri (Luo, 2001) comb. nov. Abstract L’examen de Nématodes Trichinelloidea récemment récoltés dans le tube digestif de poissons marins de Nouvelle-Calédonie, Pacifique Sud, a révélé la présence de plusieurs espèces des familles Capillariidae et Trichosomoididae, à savoir les Capillariidae Pseudocapillaria novaecaledoniensis sp. nov. du poisson de profondeur Pristipomoides argyrogrammicus (Valenciennes) (Lutjanidae) et Pseudocapillaria echenei (Parukhin, 1967) chez Echeneis naucrates Linnaeus (Echeneidae), et le Trichosomoididae Huffmanela sp. (femelle) chez Bodianus perditio (Quoy et Gaimard) (Labridae). P. novaecaledoniensis est caractérisé principalement par la structure et la longueur (318–321 µm) du spicule et la présence d’une membrane cuticulaire dorsale connectant les deux lobes ventrolatéraux chez le male (sous-genre Ichthyocapillaria Moravec, 1982). L’espèce P. echenei, auparavant peu connue, est redécrite et mentionnée pour la première fois de l’Océan Pacifique Sud. De plus, cinq différents types morphologiques de Capillariidae femelles sans identification générique, désignés comme Capillariidae gen. spp. 1–5, chacun d’eux représentant probablement une nouvelle espèce, sont mentionnés respectivement chez Fistularia commersonii Rüppell (Fistulariidae), Synodus dermatogenys Fowler (Synodontidae), Carangoides oblongus (Cuvier) (Carangidae), Diagramma pictum (Thunberg) (Haemulidae), et Stegostoma fasciatum (Hermann) (Stegostomidae). Capillaria decapteri est transféré dans Pseudocapillaria Mendonça, 1963 comme P. decapteri (Luo, 2001) comb. nov.

Anisakid nematodes commonly infect gadids, and are of economic and aesthetic importance to the commercial fishing industry in Greenland as some species are pathogenic to humans. However, very little is known about the occurrence of these parasites and their impact on the hosts in Greenland waters. During a survey in 2005, stomach sample of 227 Atlantic cod (Gadus morhua) and 64 Greenland cod (Gadus ogac) was collected in Godthaab and Sisimiut fiord systems in West Greenland waters. All cod were dissected for stomach contents and anisakid nematodes were removed from the visceral cavity. Third stage larvae (L3) of three anisakid species were found, including Contracaecum osculatum (Rudolphi, 1802), Anisakis simplex (Rudolphi, 1809) and Hysterothylacium aduncum (Rudolphi, 1802). Molecular identification by PCR-RFLP indicated the presence of A. simplex s.s. and the sibling species C. osculatum B and C. The prevalence of infection by C. osculatum was higher in Greenland cod (84.3%) than in Atlantic cod (73.9%) whereas the prevalence of A. simplex showed an opposite pattern (Greenland cod 8.3%; Atlantic cod 24.2%). Only one G. morhua (1.0%) was infected by H. aduncum. No gender specific difference in both nematode species regarding prevalence of infection and mean infection intensity was evident, and there was no relationship between fish condition and the intensity of nematode infections. Standardised for size, capelin-eating cod were in better condition and more heavily infected than fish subsisting on alternative prey at the point of collection. Hence, nematode infections in the two gadids seem governed in part by feeding behaviour, and capelin appears a significant source of larval anisakids.

Twenty-nine individual amphibians (2 families, 3 species) and 12 individual reptiles (2 families, 2 species) from Douala, Cameroon (West Africa) were examined for helminths. Seventeen (59%) of the amphibians and 11 (92%) of the reptiles were found to harbor at least 1 species of helminth; 10 (34%) of the amphibians and 4 (33%) of the infected reptiles harbored multiple infections. A cestode, 6 species of nematodes, and a pentastomid were found in the herpetofauna surveyed. Nine new host and six new geographic distribution records are reported.

Cats play an important role in the spread of Toxoplasma gondii because they are the only animals that excrete resistant oocysts into the environment. Prevalence of T. gondii antibodies in cats in Maiduguri, Northeastern Nigeria was determined using the latex agglutination test (LAT). Thirty eight cats (36.2%) were seropositive using a cut off point of 1:64 with antibody titer ranging from 1:64 to 1:1024. Seroprevalence was higher in older animals and stray cats. Age and ownership status of cats were identified as risk factors but not gender or area of capture.

A patient was admitted with fever, vomiting, restlessness and convulsions. He was febrile and unconscious. Laboratory tests showed a low platelet count and ruled out enteric fever and dengue. His peripheral blood smear was positive for Plasmodium vivax. The presence of P. vivax monoinfection was confirmed by polymerase chain reaction and DNA sequencing. The report highlights the importance of considering the possibility of complications even in P. vivax malaria and formulation of strategies accordingly.

A female Elthusa raynaudii was found attached on the roof of the mouth facing inward in a lantern shark, Etmopterus sp. in Taiwan. This was backwards to all known cymothoid attachments in the mouths of fishes. This isopod naturally occurs in the gill chamber of fishes. The attachment must have occurred accidentally. This is only the fourth time this isopod has been collected in the northern hemisphere and the first for Taiwan and this host.