Echinorhynchus brayi n. sp. (Acanthocephala: Echinorhynchidae) from Pachycara crassiceps (Roule) (Zoarcidae), a deep-sea fish

Echinorhynchus brayi n. sp. (Palaeacanthocephala: Echinorhynchidae) is described from Pachycara crassiceps (Roule) (Zoarcidae) from the Porcupine Seabight, Northeast Atlantic. The new species closely resembles E. canyonensis Huffman & Kliever, 1977, a parasite of a Pacific zoarcid, but has longer lemnisci, larger eggs and larger testes. E. brayi n. sp. can be readily differentiated from the ten other Echinorhynchus spp. recorded from deep-sea fishes (E. abyssicola, E. gadi, E. longiproboscis, E. malacocephali, E. melanoglaeae, E. muraenolepisi, E. petrotschenkoi, E. sebastolobi, E. trachyrinci and E. truttae), because it has fewer hooks per longitudinal row.     

Bathycestus brayi n. gen. and n. sp. (Cestoda: Pseudophyllidea) from the deep-sea fish Notacanthus bonaparte in the northeastern Atlantic

Bathycestus brayi n. gen., n. sp. (Pseudophyllidea: Triaenophoridae) is proposed to accommodate a new cestode from a deep-sea fish, the shortfin spine eel Notacanthus bonaparte (Notacanthiformes: Notacanthidae), from the northeastern Atlantic. The new genus is placed in the Triaenophoridae because it possesses a uterine pore on the ventral surface, a marginal genital pore, and a follicular vitellaria. Bathycestus most closely resembles Eubothrioides, Fistulicola, Probothriocephalus, and Pseudeubothrioides, which have also an unarmed scolex, a single set of genital organs per proglottid, an unarmed cirrus, cortical vitellaria, and a compact rather dendritic ovary. It differs from these genera by combination of the following features: a sagittate scolex with a weakly developed apical disc and free posterior margins of bothria, no neck, a long cirrus sac, reaching to the median third of proglottids and angled anteromedially in its proximal part, the posterior position of the vagina in relation to the cirrus sac, the testes in 2 lateral fields confluent postovarially, circumcortical vitellaria continuous longitudinally, and unoperculate eggs. Bathycestus brayi n. sp. is the first cestode to be described from a deep-sea fish of the genus Notacanthus.     

Steganoderma (Steganoderma) valchetensis n. sp. (Digenea: Zoogonidae) from the relict fish Gymnocharacinus bergi (Osteichthyes: Characidae) in Argentina

A new species of Steganoderma (Steganoderma) (Digenea: Zoogonidae) was found in the digestive tract of the southernmost, endemic and scale-less characid, Gymnocharacinus bergi, inhabiting thermal headwaters of the Valcheta Creek in northern Patagonia, Argentina. Steganoderma valchetensis n. sp. is included in the subgenus Steganoderma because of having a sessile ventral sucker and caeca reaching to the testes. This new species can be distinguished from other species of this genus on the basis of body-length, sucker-ratio, the length of the cirrus-sac, the morphology of the seminal vesicle and gonads, and the location of the vitelline follicles and genital pore. The taxonomic status of the species of Steganoderma, parasitising the freshwater fishes of Patagonia, in southern Argentina, and Chile, is also discussed.     

Diplobulbus brayi n. sp. (Digenea: Opecoelidae) from Odax acroptilus (Perciformes: Odacidae) off Western Australia

Diplobulbus brayi n. sp. is described from the small intestine of Odax acroptilus (Perciformes: Odacidae) from Point Peron in southern Western Australia. One of the five previously described species of Diplobulbus, D. vitellosus Bilqees, 1972 from Tetraodon lunaris (now Lagocephalus lunaris), is synonymised with Alloheterolebes indicus (Gupta, 1968) Hafeezullah, 1971, which is known from the same host in the Indian Ocean. D. brayi n. sp. can be distinguished from the remaining four species of Diplobulbus by the distinct interruption of the vitelline follicles at the ventral sucker, its more elongate form and its long post-testicular space. Diplobulbus is so far restricted to the Indo-Pacific region and appears to be stenoxenic to labroid fishes. This is the first record of a trematode from an odacid fish.     

Abyssotrema pritchardae gen. et sp. n. (Digenea: Fellodistomidae) from the deep-sea fish, Alepocephalus agassizi Goode and Bean 1883.

Abyssotrema pritchardae gen. et sp. n. is described from the benthic teleost, Alepocephalus agassizi Goode and Bean 1883 (Alepocephalidae), taken from Hudson Canyon in the western North Atlantic. The new genus is placed in the subfamily Monascinae Dollfus 1947 and relationships among Abyssotrema, Elopsium Fischthal and Thomas 1972, and Monascus Looss 1907 are discussed.     

Fellodistomidae and Zoogonidae (Digenea) of deep-sea fishes of the NW Atlantic Ocean

The following species are described from fishes in deep-waters of the northwestern Atlantic Ocean: Fellodistomidae: Steringophorus furciger from Antimora rostrata, Coryphaenoides (Lionurus) carapinus, Lycenchelys paxillus, L. verrillii and Lycodes atlanticus; S. blackeri from Xenodermichthys copei, S. haedrichi n. sp. from Porogadus milesi, characterised by its lobate testes, sucker-ratio and long vitelline fields Megenteron crassum from Dicrolene intronigra; Zoogonidae: Brachyenteron rissoanum n. sp. from Polyacanthonotus rissoanus, characterised by the ovary position, the saccular seminal vesicle, the marginal genital pore and egg-size; Koiea notacanthi n. g., n. sp. from Notacanthus (?) chemnitzi, characterised by the Y-shaped excretory vesicle and the posteriorly placed testes.     

Overstreetia olsoni n. sp. (Digenea: Zoogonidae) from the Capricorn silverside Atherinomorus capricornensis (Woodland) (Atherinidae) off Heron Island, southern Great Barrier Reef

A new species, Overstreetia olsoni, is described from Atherinomorus capricornensis off Heron Island on the Great Barrier Reef off Queensland, Australia. It differs from its only known congener in that the enlarged spines of the circum-oral rows are smaller ( ≤ 4.5 × 3.5 vs ≤ 21.5 × 10.5μm), the sucker-ratio is smaller (1: 0.97–1.01 vs 1:1.8) and the eggs are larger (40–45 × 22–28 vs 34–37 × 17–22μm).     

Australicola pectinatus n. gen. and n. sp. (Cestoda: Pseudophyllidea) from the deep-sea fish Beryx splendens from Tasmania

Australicola pectinatus n. gen., n. sp. (Pseudophyllidea: Triaenophoridae) is proposed to accommodate a new cestode from a deep-sea fish, the splendid alfonsino, Beryx splendens Lowe, 1834 (Beryciformes: Berycidae), from the Pacific coast of Tasmania. The new genus is placed in the Triaenophoridae, because it possesses a ventral uterine pore, marginal genital pore, and follicular vitellarium. Australicola is characterized by possessing a massive strobila with very short and wide, markedly craspedote proglottids; vitelline follicles forming a transverse equatorial band; a very deep and narrow genital atrium; a wide, convoluted vaginal canal; and unoperculate eggs. Australicola most closely resembles Eubothrium Nybelin, 1922 and Probothriocephalus Campbell, 1979 in having an unarmed scolex, an unarmed cirrus, the vagina anterior to the cirrus-sac, and cortical vitellaria. It differs from these 2 genera, in addition to the characteristics listed above, in possessing a dendritic rather than an entire ovary. Australicola pectinatus n. sp. is the third cestode described from B. splendens.     

Pirupalkia queulensis n. gen., n.sp. (Digenea: Callodistomidae) in the fish Cilus montti (Pomadasyidae)

A new genus and species of the subfamily Callodistomidae is described. The new genus is named Pirupalkia queulensis n. gen., and was found in the small intestine of the fish Cilus montti. This new genus, compared with other genus of the subfamily differs principally in the distribution of the vitellaria and location of the uterus.     

The genus Deretrema Linton, 1910 (Digenea: Zoogonidae) from southern Great Barrier Reef fishes,with a description of Deretrema woolcockae n. sp.

Two species of Deretrema (Zoogonidae) are reported from labrid fishes from the Great Barrier Reef. D. nahaense Yamaguti, 1942 is recorded from the gall-bladders of the labrids Thalassoma hardwicke (Bennett), T. jansenii (Bleeker), T. lunare (Linnaeus) and T. lutescens (Lay & Bennett). This species is recognised, despite having been formerly synonymised with D. pacificum Yamaguti, 1942. In addition to morphological distinction, D. nahaense appears to have strict host-specificity for the genus Thalassoma. D. woolcockae n.sp. is described from the gallbladder of Hemigymnus fasciatus (Bloch). The new species is close to D. acutum Pritchard, 1963 and D. plotosi Yamaguti, 1940, but differs slightly in the distribution of the vitelline follicles, the sucker-ratio and the position of the cirrus-sac. In addition, this species also appears to have a distinct host-specificity, being restricted to one labrid species.     

Sympatric species of Deretrema Linton, 1910: D. combesae n. sp. and D. combesorum n. sp. (Digenea: Zoogonidae) from the manybar goatfish Parupeneus multifasciatus (Quoy & Gaimard, 1824) (Perciformes: Mullidae) from New Caledonia

Two sympatric species of Deretrema, D. combesae n. sp. and D. combesorum n. sp. are described from the manybar goatfish Parupeneus multifasciatus from off New Caledonia, South Pacific. D. combesae n. sp. does not fit any of the described Deretrema subgenera. The combination of the characters, tegumental spines, caeca reaching past the testes, the vitellarium reaching into the hindbody, much of the uterus at the level of and anterior to the gonads, a long oesophagus, testes in the hindbody and the pre-testicular ovary are not found in any of the described subgenera. D. combesorum n. sp. fits into the subgenus Deretrema (Deretrema), but differs from the described species in the sucker-ratio, eggs size, elongate shape and contiguous testes. The sympatry of these dissimilar species of Deretrema casts doubt on the value of the subgenera in Deretrema.     

Boreascotia megavesicula n. g., n. sp. (Digenea: Hemiuridae: Lecithochiriinae) in the nototheniid fish Lepidonotothen macrophthalma (Norman) from the sub-Antarctic Atlantic

Boreascotia megavesicula n. g., n. sp. is described from the intestine of the fish Lepidonotothen macrophthalma from the North Scotia Ridge, Sub-Antarctic, Atlantic Ocean. The new genus has an ecsoma, placing it in the family Hemiuridae, and a distinct prostatic vesicle, placing it in the subfamily Lecithochiriinae, but is distinct from the other members of the subfamily in having an elongate, tubular seminal vesicle, which reaches well into the hindbody and overlaps the anterior testis.     

Probothriocephalus alaini n. sp. (Cestoda: Triaenophoridae) from the deep-sea fish Xenodermichthys copei in the North Atlantic Ocean

Probothriocephalus alaini n. sp. is described from the intestine of the deep-sea fish Xenodermichthys copei (Gill) (Osmeriformes: Alepocephalidae) from the North Atlantic. It resembles most closely the type-species of Probothriocephalus, P. muelleri Campbell, 1977 described from Alepocephalus agassizi Goode & Bean (Alepocephalidae), but it differs in the distribution of the vitelline follicles that form two medially well-separated bands (versus almost circum-cortical in P. muelleri), in the shape of gravid proglottids that are elongate, much longer than wide (always wider than long in P. muelleri), in the size of the body (much larger in the latter species) and a somewhat different shape of the scolex (widely lanceolate versus elongate and tapering anteriorly in P. muelleri). Other congeneric species, described from deep-sea fish of different orders (Myctophiformes and Beryciformes), lack a distinct neck region, their eggs were reported to be non-operculate and they have much more pronounced external segmentation.     

Description of Auriculotrema lechneri n. gen., n. sp. (Digenea: Choanocotylidae), a parasite of freshwater turtles (Testudines: Pleurodira: Chelidae) from Queensland,Australia

Auriculotrema lechneri n. gen., n. sp. is described from the small intestine of Emydura krefftii and Elseya latisternum from northern Queensland, Australia. The new species strongly resembles species of Choanocotyle in body shape, ventral incision of the oral sucker, structure of the cirrus sac, and location of the genital pore. The distinctive taxonomic feature is the presence of 2 winglike projections extending beyond the lateral margins of the oral sucker, in contrast to the extremely large, expanded oral sucker diagnostic of Choanocotyle spp. Auriculotrema n. gen. is the second genus included in the formerly monotypic Choanocotylidae Jue Sue and Platt, 1998.     

Macvicaria taksengi n. sp. (Digenea: Opecoelidae) in marine teleosts from Pinang,Malaysia

Summary A new species, Macvicaria taksengi (Opecoelidae: Plagioporinae), is described from the fishes Otolithes ruber and Sillago sihama from Pinang, Malaysia. It differs from most other members of the genus in the position of the ovary relative to the testes and the anterior position of the genital pore. A brief discussion on the Indo-West Pacific forms of the genus Macvicaria and related genera includes references to several new combinations: M. [Lebouria] isaitschikowi (Layman, 1930), M. [Plagioporus] sillagonis (Yamaguti, 1938), M. [Plagioporus] chrysophrys (Nagaty & Abdel Aal, 1969) and M. [Plagioporus (Plagioporus)] longisaccus (Fischthal & Kuntz, 1964).     

Ultrastructural studies of Henneguya rhamdia n. sp. (Myxozoa) a parasite from the Amazon teleost fish, Rhamdia quelen (Pimelodidae)

Henneguya rhamdia n. sp. is described in the gill filaments of the teleost fish Rhamdia quelen, collected from the Peixe Boi River, State of Pará, Brazil. This myxosporean produced spherical to ellipsoidal plasmodia, up to 300 microm in diameter, which contained developmental stages, including spores. Several dense bodies up to 2 microm in diameter were observed among the spores. The spore body was ellipsoidal (13.1 microm in length, 5.2 microm in width, and 2.5 microm in thickness) and each of the two valves presented a tapering tail (36.9 microm in length). These valves surrounded the binucleated sporoplasm cell and two equal ellipsoidal polar capsules (4.7 x 1.1 microm), which contained 10-11 (rarely 12) polar filament coils. The sporoplasm contained sporoplasmosomes with a laterally eccentric dense structure with a half-crescent section. Based on the data obtained by electron microscopy and on the host specificity, the spores differed from previously described Henneguya species, mainly in their shape and size, number and arrangement of the polar filament coils, and sporoplasmosome morphology.     

Baiohelmins elegans n. g., n. sp. (Digenea: Nanophyetidae) from the Australian water rat,Hydromys chrysogaster

A new genus and species of nanophyetid,Baiohelmins elegans, is described from the intestine of the Australian water rat,Hydromys chrysogaster Geoffroy, 1804 in North Queensland. The new genus differs from previously described forms by the combination of the following characters: vitelline follicles restricted to a small group posterior to each testis, cirrus pouch present and caeca not extending posterior to the ventral sucker.     

Gyrodactylus quadratidigitus n. sp. (Monogenea: Gyrodactylidae), a parasite of the leopard-spotted goby Thorogobius ephippiatus (Lowe) from the south-western coast of the UK

Gyrodactylus quadratidigitus n. sp. (Monogenea, Gyrodactylidae) is described from the gills, fins and skin of Thorogobius ephippiatus (Lowe) (leopard-spotted goby) from Portland Castle Bay, Dorset, UK. G. quadratidigitus n. sp. most closely resembles the species ofGyrodactyluspreviously described by Geets from Pomatoschistus microps(Krøyer) in the approximate shape and size of the attachment hooks but can be readily distinguished from other species of the genus by the distinctive square shape of the toe region of the marginal hook sickle, the anteriorly positioned cirrus bulb and the unusually short intestinal crura which extend only as far as the level of the testes.