Volume 55, Issue 3

We used a nested PCR protocol to examine the genetic diversity of cytochrome b (cyt b) lineages from blood parasites of the genera Plasmodium and Haemoproteus in birds in Bulgaria. In total, 460 birds of 43 species and 14 families (mostly passerines) were examined for the presence of infections. Of them, 267 were recognised as infected with haemosporidian parasites. Mixed infections were recorded in 24 individuals (9%). Besides the 24 individuals with mix infections, 114 (43%) were positive for Plasmodium spp. and 129 (48%) for Haemoproteus spp. We identified 52 genetic lineages of haemosporidian parasites: 38 of Haemoproteus and 14 of Plasmodium. Twelve new cyt b lineages of Haemoproteus were recorded; they occurred in the following hosts: grey-faced woodpecker (Picus canus), golden oriole (Oriolus oriolus), jay (Garrulus glandarius), barred warbler (Sylvia nisoria), song thrush (Turdus philomelos), spotted flycatcher (Muscicapa striata), spanish sparrow (Passer hispaniolensis), hawfinch (Coccothraustes coccothraustes), and cirl bunting (Emberiza cirlus). We also detected 22 new host records for previously known lineages. The most common lineage was SGS1 (Plasmodium relictum), which had a total prevalence of 14% and occurred in 8 host species belonging to 5 families. Three of the cyt b lineages of genus Haemoproteus (DURB1, DURB2 and SYNIS2) showed more than 5% divergence from all described morphologically lineages. These lineages probably represent at least 2 different morphospecies which remains to be identified.

Molecular detection of apicomplexan parasites in splenic samples of red foxes collected from northeastern Poland was conducted by PCR amplification of a fragment of the 18S rRNA spanning the V4 gene region of Apicomplexa. Positive PCR products were further analysed by restriction fragment length polymorphism (RFLP) and sequencing to identify species. One hundred and eleven red foxes (Vulpes vulpes) were acquired from 15 localities in the Mazovian Province and 27 foxes were acquired from the Mazurian Lakeland. Apicomplexan 18S rDNA was detected in 15.9% of 138 fox spleens examined. Three apicomplexan species were identified: Hepatozoon canis was detected in 11.6% of the spleen samples, Toxoplasma gondii was detected in 3.6% of the spleen samples and a Babesia sp. was sequenced from 1 sample (0.7%). This data represent the first record of H. canis, T. gondii and a B. sp. from naturally infected red foxes in Poland. Infected foxes may act as sylvatic reservoirs of these apicomplexan parasites as well as serving as a source of infection for arthropod definitive hosts and vectors.

Gyrodactylus infections in intensively-reared populations of Nile tilapia, Oreochromis niloticus niloticus, have been associated world-wide with high mortalities of juvenile fish. In this study, 26 populations of Gyrodactylus parasitising either O. n. niloticus or Mozambique tilapia, Oreochromis mossambicus, were sampled from fourteen countries and compared with type material of Gyrodactylus cichlidarum Paperna, 1968, Gyrodactylus niloticus (syn. of G. cichlidarum) and Gyrodactylus shariffi Cone, Arthur et Bondad-Reantaso, 1995. Representative specimens from each population were bisected, each half being used for morphological and molecular analyses. Principal component analyses (PCA) identified five distinct clusters: (1) a cluster representing G. cichlidarum collected from O. n. niloticus from 13 countries; (2) the G. shariffi paratype; (3) three specimens with pronounced ventral bar processes collected from two populations of Mexican O. n. niloticus (Gyrodactylus sp. 1); (4) four specimens collected from an Ethiopian population nominally identified as O. n. niloticus (Gyrodactylus sp. 2); (5) nine gyrodactylids from South African O. mossambicus (Gyrodactylus sp. 3). Molecular analyses comparing the sequence of the ribosomal transcribed spacer regions (ITS 1 and 2) and the 5.8S gene from the non-hook bearing half of worms representative for each population and for each cluster of parasites, confirmed the presence of G. cichlidarum in most samples analysed. Molecular data also confirmed that the DNA sequence of Gyrodactylus sp. 2 and Gyrodactylus sp. 3 (the morphologically-cryptic group of South African specimens from O. mossambicus) differed from that of G. cichlidarum and therefore represent new species; no sequences were obtained from Gyrodactylus sp. 1. The current study demonstrates that G. cichlidarum is the dominant species infecting O. n. niloticus, being found in 13 of the 15 countries sampled.

Petasiger argentinensis sp. nov. is described from material found in the intestine of the Great Grebe, Podiceps major (Boddaert) and the White-tufted Grebe, Rollandia rolland Quoy et Gaimard (Podicipediformes, Podicipedidae), from Argentina. The new species is characterized by the head collar armed with 19 spines and by the testes arranged in tandem. These characters are shared with only two Neotropical species of the genus, P. novemdecim Lutz, 1928 and P. combesi Zamparo, Overstreet et Brooks, 2005. Petasiger novemdecim differs from the new species in having a larger body, longer collar spines, larger eggs, a cirrus-sac of similar size to the ventral sucker and almost entirely anterior to it, and vitelline fields confluent ventrally posterior to the ventral sucker. P. combesi differs from the new species in most metrical characters, the shape of the body (antero-posteriorly elongate) and the location of the genital pore (dextral) and the excretory pore (dorsal). This is the first record of a member of the genus Petasiger parasitizing birds from Argentina.

A new species of opecoelid trematode, Pseudopecoelus brayi sp. nov. is reported from the holocentrid fish, Myripristis kuntee collected from off Visakhapatnam coast, Bay of Bengal. The new species differs from related species by a combination of characters such as elongate body, deeply lobed gonads, tubular sinuous seminal vesicle extending up to the posterior border of ventral sucker, presence of a short cylindrical cirrus sac enclosing the cirrus and the vitelline zone extending anterior to ventral sucker. This is the 7th species of the genus to be reported from Indian marine fishes and the fifth species from holocentrid fishes. A key for separation of the species of Pseudopecoelus is given.

Proctocaecum blairi sp. nov. is described from specimens found in the intestine of an Australian freshwater crocodile, Crocodylus johnstoni, from Northern Territory, Australia. The most important diagnostic features of the new species are the body proportions and size, the position of the pharynx (relative length of the prepharynx and oesophagus), the relative length and position of the vitelline fields, and the number, shape and size of the circumoral spines. The new species is morphologically most similar to Proctocaecum atae, P. elongatum, P. crocodili, P. gairhei and Acanthostomum slusarskii. It differs from all of these species in having a much longer prepharynx, and differs from both P. atae and P. crocodili in having a much longer body and posteriorly situated vitelline fields. Proctocaecum blairi sp. nov. differs from P. elongatum in having a shorter body, a greater forebody to hindbody ratio, a much smaller ventral sucker, and a higher number of circumoral spines (23 vs 21 in P. elongatum). The new species differs from P. gairhei in possessing a much larger body length:width ratio and an ovary separated from the anterior testis by a seminal receptacle. Acanthostomum slusarskii lacks a gonotyl and has fewer circumoral spines than the new species. Proctocaecum blairi sp. nov. is the third species of Proctocaecum and the fourth cryptogonimid species known from crocodiles in Australia.

The intrauterine, mature and fully embryonated eggs of the prosthogonimid trematode Mediogonimus jourdanei Mas-Coma et Rocamora, 1978 were examined by means of transmission electron microscopy (TEM), using high pressure freezing, freeze substitution and infiltration with resin techniques. Each embryonated egg is composed of a miracidium surrounded by three envelopes: (1) the egg shell, (2) the outer and (3) inner envelopes. Egg envelopes play an important role in the protection, metabolism, storage of nutritive reserves and the general biology of the M. jourdanei egg. The inner envelope is characterised by large, flattened nuclei, and its syncytial cytoplasm contains a heavy accumulation of glycogen, lipid droplets, mitochondria and large vesicles. These traits indicate that this layer has the features of a metabolically-active syncytial layer with an energy storage capability. In the infective eggs observed before the hatching of the miracidium, areas of so-called “focal cytoplasmic degradation” were frequently observed, which may be involved in the autolytic process of all components of this envelopes.

The intrauterine polylecithal eggs of the spathebothriidean cestode Didymobothrium rudolphii (Monticelli, 1890) were examined by means of transmission electron microscopy (TEM). Each unembryonated egg is composed of a fertilised oocyte or ovum and several vitelline cells, all surrounded by a newly formed shell. The lumen of the proximal uterus is packed with unutilised vitelline material and eggs at different stages of shell formation. In the proximal region of the uterus, the fertilised oocytes, initially surrounded by dense, discontinuous islands of eggshell material and containing long axonemes of spermatozoa in their cytoplasm, were frequently observed. Sperm axonemes also remain in the oocyte cytoplasm of eggs surrounded by a thick electron-dense shell until the sperm nucleus is transformed into a male pronucleus. Despite the fact that the two-pronuclei stage and cell divisions within the eggs of D. rudolphii were never observed, individual eggs containing several blastomeres of different sizes were seen in the middle and distal regions of the uterus. This provides indirect evidence that at least a few initial cleavage divisions must take place in the intrauterine eggs and direct evidence that the early embryonic development of D. rudolphii starts in utero. The several vitellocytes present in each egg contain nutritive reserves for the developing embryos; these are composed mainly of numerous lipid droplets and a moderate amount of glycogen. In the eggs containing early embryos composed of several blastomeres, the cytoplasm of the degenerating vitellocytes exhibits the presence of so-called ‘foci of cytoplasmic degradation’, which appear to be involved in the autolytic process of the vitellocyte cell components and inclusions, such as a high accumulation of lipids and glycogen. This progressive degeneration of the vitellocytes, considered as an example of programmed cell death or apoptosis, likely contributes towards the resorption of nutritive reserves by the developing embryo. Some of the results of this study are commented upon in relation to the affiliation of the spathebothriideans with other lower cestode groups.

Lemuricola (Madoxyuris) bauchoti Chabaud, Brygoo et Petter, 1965 is redescribed from material collected from the ring-tailed lemur, Lemur catta, from the Beza Mahafaly Special Reserve in Madagascar using the scanning electron microscope. This is a new host record and the first oxyurid reported from the ring-tailed lemur. Previously, records of each species of the subgenus Madoxyuris have been restricted to a single host species, but the close relationship between these nematodes and their Strepsirrhini hosts will only be proven when additional records fill in the gaps in their distribution.

A new species of Rhabdochona is described as a parasite of two endemic species of catfishes (Ictalurus dugesii and Ictalurus pricei) from two river basins in central and northern Mexico (Río Ameca and Río Tunal). Rhabdochona ictaluri sp. nov. is characterized by a combination of morphological traits that include the presence of basal teeth, bifurcated deirids, absence of a dorsal barb in left spicule and length ratio between spicules. The combination of these traits readily distinguishes the new species from all its congeners, including those species possessing 14 teeth in the prostom. The new species appears to be specific to freshwater ictalurids.

The presence of larvae and pupae of the genus Metrichia (Trichoptera, Hydroptilidae), larvae of the genus Macrelmis and Phanocerus (Coleoptera, Elmidae), three diatom genera Achnanthes, Cocconeis, Gomphonema, and some specimens of very small diatoms that could not be determined to species or genus level, were recorded for the first time as epibionts for Chordodes brasiliensis (Gordiida, Nematomorpha). Such epibionts were found on the body surface of this species of hairworms, captured from El Tala stream, Catamarca, Argentina.

A blotched fantail ray, Taeniurops meyeni (Müller et Henle, 1841), was captured in New Caledonia, South Pacific, and kept in a tank for quarantine before exhibition at the Nouméa public aquarium. After 24 days, the ray exhibited a heavy infection with two species of skin monogeneans. A freshwater bath allowed the collection of 1,914 monogeneans, including 1,453 capsalids, Neoentobdella taiwanensis Whittington et Kearn, 2009, on the ventral surface, and 461 monocotylids, Dendromonocotyle pipinna Chisholm et Whittington, 2004, on the dorsal surface. More than 300 monogeneans were prepared on slides to allow precise measurements. Capsalids and monocotylids occupied about 6% and 0.2% of the total ventral and dorsal ray surfaces, respectively. Abstract Une raie, Taeniurops meyeni (Müller et Henle, 1841), a été capturée en Nouvelle-Calédonie, Pacifique Sud, et gardée dans un bac en quarantaine avant exposition à l’Aquarium de Nouméa. Après 24 jours, la raie a montré une forte infection par deux espèces de monogènes de la peau. Un bain d’eau douce a permis la récolte de 1914 monogènes, dont 1453 Capsalidae, Neoentobdella taiwanensis Whittington et Kearn, 2009 sur la surface ventrale, et 461 Monocotylidae, Dendromonocotyle pipinna Chisholm et Whittington, 2004 sur la surface dorsale. Plus de 300 monogènes ont été montés en lames pour permettre des mesures précises. Les Capsalidae et les Monocotylidae occupaient approximativement 6% et 0,2% des surfaces ventrale et dorsale de la raie, respectivement.

The first record of Pseudione crenulata in the branchial chamber of Munida intermedia is reported from the southern Tyrrhenian Sea, with notes on accessory males and female morphology. The effects of this parasite on host pleopod morphology are reported. Pseudione crenulata has previously been recorded from M. tenuimana and M. rugosa, both in the Atlantic Ocean and the Mediterranean Sea.