Monorchis lewisi n. sp. (Trematoda: Monorchiidae) from the surf bream, Acanthopagrus australis (Sparidae), in Moreton Bay, Australia

We describe Monorchis lewisi n. sp. (Monorchiidae) from the surf bream, Acanthopagrus australis (Günther, 1859) (Sparidae), in Moreton Bay, eastern Australia. The new species differs from most existing species of Monorchis Monticelli, 1893 in its possession of an elongate I-shaped excretory vesicle, and from other congeners in the relative configuration of the gut and suckers. Ovipusillus mayu Dove & Cribb, 1998 is re-reported from Gnathanodon speciosus (Forsskål, 1775) (Carangidae) from Moreton Bay. We report new second internal transcribed spacer (ITS2) and 28S rDNA sequence data for both species. Bayesian inference and Maximum Likelihood analyses of the 28S rDNA dataset suggest that existing subfamily and genus concepts within the family require substantial revision.

Microtrema barusi gen. n. and sp. n. (Digenea: Phaneropsolidae) from Prunella modularis (Aves, Passeriformes) in the Czech Republic

Microtrema gen. n. and Microtrema barusi sp. n. are described from the intestine of Prunella modularis in the Czech Republic. Genus and species have the following features: Body claviform, widest in region of ventral sucker. Tegument densely covered with tiny spines. Suckers small, widely separated. Oral sucker globular, subterminal. Ventral sucker globular, equatorial. Prepharynx very short or absent. Pharynx small, fine. Oesophagus divided into two short intestinal branches ending blindly anterior to testes. Testes globular, lateral, in region of ventral sucker. Vesicula seminalis small, genital pore in short distance before ventral sucker and opening of uterus. Bursa cirri and cirrus absent. Ovary globular, median, between testes. Mehlis’ gland long oval, posterior to ovary. Vitellarium weakly developed, in two lateral clusters composed of small follicles. Uterus in posterior part of body, with many eggs, covering vitellarium and partly ventral sucker. Excretory vesicle V-shaped, pore terminal.

Paramonostomum bubaki n. sp. (Digenea: Notocotylidae) from the Black Coot, Fulica atra (Gruiformes: Rallidae), in South Central Pakistan

During a helminthological survey of black coot, Fulica atra (Gruiformes: Rallidae), in Sindh Province of Pakistan, eight specimens of undescribed species of trematode belonging to genus Paramonostomum Lühe, 1909 were recovered from large intestine of the single host bird. Paramonostomum bubaki n. sp. differs from its congeners except P. macrovesiculum Dharejo et al., 2006 by having less attenuated anterior end, a pharynx, a bifurcal genital pore, a longer posttesticular space, a Y-shaped excretory vesicle, number of uterine loops (16), and large size of filamentous eggs. P. bubaki n. sp. resembles P. macrovesiculum Dharejo et al., 2006 collected from Fulica atra from Pakistan by having a pharynx but differs in larger body, smaller esophagus, a bifurcal genital pore, shape of cirrus sac, seminal vesicle and gonads, ceca reaching posterior extremity, and a longer posttesticular space.

Peracreadium akenovae sp. nov. (Trematoda: Opecoelidae) parasitising the highfin moray eel Gymnothorax pseudothyrsoideus (Anguilliformes: Muraenidae) from moreton bay, Australia

A new opecoelid trematode, Peracreadium akenovae sp. nov., is described from the highfin moray eel Gymnothorax pseudothyrsoideus (Bleeker) (Anguilliformes; Muraenidae), collected from Moreton Bay off southeast Queensland, Australia. The new species is distinctive in its body shape, transversely elongate irregular testes, vitelline follicles interrupted at the level of the ventral sucker, and diverticulate excretory vesicle. The Muraenidae is a new host family for Peracreadium Nicoll, 1909. Peracreadium is the seventh opecoelid genus reported from temperate eastern Australian marine fishes and this is its first report from Australian waters.

Description of Neolepidapedoides subantarcticus sp. nov. (Digenea, Lepocreadiidae) from sub-Antarctic notothenioid fishes

Neolepidapedoides subantarcticus sp. nov. (Digenea, Lepocreadiidae) is reported from the intestine, mainly the jejunum, of fishes in the eastern mouth of the Beagle Channel and in the harbour of Ushuaia in the Beagle Channel (Tierra del Fuego, Argentina) at a depth 7–30 m. The typical host is Patagonotothen longipes, other hosts are P. tessellata, P. brevicauda and Champsocephalus esox. The male terminal genitalia indicates that the new species belongs to the genus Neolepidapedoides (Lepocreadiidae, Lepocreadiinae). The most important taxonomic features are the presence of eye-spots, the spined tegument, the “Opechona-type” cirrus-sac, the external seminal vesicle free in the parenchyma, the gonads arranged in tandem, the vitelline follicles extending from the level of the oesophagus in the forebody to the posterior end of the body and an I-shaped excretory vesicle reaching to the intestinal bifurcation and the absence of a pseudoesophagus. Ten previously described species differ from the N. subantarcticus sp. nov. mainly in the extent of the vitelline fields and length of the excretory vesicle which reaches into forebody.

Steringovermes notacanthi n. gen., n. sp. (Digenea: Fellodistomidae) from the deep-sea spiny eel Notacanthus bonaparte (Notacanthiformes: Notacanthidae) from the north eastern Atlantic and a new host record for Olssonium turneri

Steringovermes notacanthi, a new genus and species of fellodistomine digenean, is described from the deep-sea spiny eel Notacanthus bonaparte from below 1,000m depth in the north eastern Atlantic. It differs from other related genera in the unique combination of a V-shaped excretory vesicle, multilobate, mainly post-testicular ovary and extensive vitelline fields extending into both the foreand hindbody. In addition, the fellodistomine Olssonium turneri Bray & Gibson, 1980 is reported for the first time from a fish not of the genus Alepocephalus, namely the alepocephalid Narcetes stomias.

Macrourimegatrema brayi n. gen., n. sp. (Digenea: Opecoelidae) from four species of deep-sea macrourid fishes from the Gulf of Mexico and Caribbean Sea, with a list of endohelminths reported from species of Bathygadus and Gadomus (Macrouridae)

Macrourimegatrema brayi n. gen., n. sp. (Digenea: Opecoelidae: Plagioporinae) is described from the pyloric ceca and intestines of 4 species of bathygadine macrourid fishes collected from deep waters of the Gulf of Mexico and off Colombia and Panama. Macrourimegatrema n. gen. can be distinguished from all other genera in the subfamily by possessing a combination of the following diagnostic characteristics: an atypically large elongate body; a short, distinct forebody separated from a long hindbody by a distinct constriction at the level of the acetabulum; a terminal, funnelshaped oral sucker; nearly equatorial ovary and testes and an unusual tubular excretory vesicle that winds between the 2 tandem testes. Macrourimegatrema n. gen. is most similar to the genus Anabathycreadium, but the former differs in having a smaller body size (6,000 vs 15,500 m); a funnelshaped oral sucker; a slightly protuberant acetabulum; suckers of equal size; an oval pharynx (rather than being ring-shaped); ceca that terminate some distance from the posterior extremity; a smaller cirrus sac that reaches only a short distance postacetabularly (rather than reaching to the level of the ovary); a genital pore that is bifurcal to slightly prebifurcal (rather than being at the posterior margin of the pharynx); numerous, small, follicular vitelline follicles that approach the level of the acetabulum anteriorly (rather than terminating well short of the level of the acetabulum); an ovary that is immediately pretesticular (rather than being far removed anteriorly from the anterior testis) and M. brayi n. gen., n. sp. has an unusual tubular excretory vesicle that winds between the 2 testes. Species of opecoelids are expected to utilize either a crustacean or fish second intermediate host, and the lack of fish reported for the food preferences of members of Bathygadinae studied here suggest that M. brayi n. gen., n. sp. probably infects its host through ingestion of a near-bottom pelagic crustacean. The precedence of using general body morphology of the species or its conformation to the characteristics of the 4 subfamilies of Opecoelidae is discussed.

Cryptocotyle lingua in mullet, Chelon labrosus; significance of metacercarial excretory proteins in the stimulation of the immune response

Abstract‘O’ group mullet, Chelon labrosus. were experimentally infected with Cryptocotyle lingua (Heterophyidae) by tail dip in a suspension of cercariae. Metacercariae were excised after 1 and 24 hours and prepared for TEM and post-embedding immunogold labelling. Antisera to cercariae of C. lingua were raised in adult mullet by natural infection via the skin and by intra-peritoneal injection of sonicate. The membrane-bound vesicles within the syncytial lining of the metacercarial excretory vesicle were found to be intensely antigenic with both antisera: the epidermal secretory bodies type 5 within the cystogenousglands gave a positive response. Penetration gland contents were not found to be antigenic with either antiserum. Discharge of the membrane-bound vesicles coinciding with both the reorganization of the lining of the metacercarial excretory vesicle and with cyst wall formation appears to be of significance in the initiation of the host immune response. That the term ‘excretory vesicle’ in Digenea may be a misnomer is discussed in the light of current information regarding the wide range of functions attributed to this structure.

The ecsoma in Hemiuridae (Digenea: Hemiuroidea): tegumental structure and function in the mesocercaria and the metacercaria of Lecithochirium furcolabiatum (Jones, 1933) Dawes, 1947

Ultrastructural, histochemical and autoradiographical techniques have been used to investigate the development and function of the tegument of both somal and ecsomal body regions in the hemiurid Lecithochirum furcolabiatum. The terms mesocercaria and metacercaria are here adopted for those stages in the copepod second and fish third intermediate hosts respectively on the basis of morphology and on analogy with the Strigeidae. Mesocercariae were obtained by experimental infection of the harpacticoid copepod Tigriopus brevicornis with the cystophorous cercariae (syn. Cercaria vaullegeardi), whilst metacercariae were removed from the body cavities of naturally-infected rockpool teleosts including Gobius paganellus and Blennius pholis. Observations on the mesocercaria show the origin of the ecsoma from the distal half of the excretory vesicle, which at 21 days post-infection is capable of eversion through the terminal pore. The nucleated microrugous surface layer of the ecsoma at this stage is modified or replaced in the metacercaria by anucleate syncytial tegument similar to that of the adult organ. The metacercarial stage is also associated with the more advanced development of the somal tegument. The two stages differ in metabolic activity, the somal tegument of only the metacercaria resembling that of the adult in acid phosphatase distribution. In the mesocercaria the ecsomal tegument showed the strongest uptake of 3H-tyrosine; absorption of the latter was not detected in the metacercaria. 3H-glucose uptake was restricted to the intestinal caeca of both stages.

Redescription of Falcaustra duyagi (Tubangui &Villaamil, 1933) Freitas &Lent, 1941 (Nematoda: Cosmocercoidea) from Cuora amboinensis (Testudinidae) of Malaysia

Falcaustra duyagi (Tubangui &Villaamil, 1933) Freitas &Lent, 1941 is redescribed based on specimens from Cuora amboinensis (Testudinidae) of Malaysia (new locality record). These specimens differ only slightly from the original description in dimensions and appearance of caudal pseudosuckers in males. This work elucidates details of cephalic morphology, the excretory system and the gubernaculum, which may provide useful taxonomic information. Falcaustra duyagi is distinguished from other Asian species by the number of pseudosuckers, short spicules bearing numerous prominent protuberances on the anterior portion, and by the large saccular excretory vesicle lacking lateral canals. Cephalic morphology of F. duyagi was studied from stained histologic sections. The cheilostome and oesophastome are similar to Falcaustra stewarti Baylis &Daubney, 1922. Falcaustra stewarti is reported from Cyclemys mouhoti (Testudinidae) of southern Viet Nam (new host and locality record).