Heliocotyle ewingi sp. n. (Monogenea: Monocotylidae) from the gills of Myliobatis australis (Myliobatididae) from Tasmania, Australia

Heliocotyle ewingi sp. n. (Monogenea: Monocotylidae) is described from the gills of Myliobatis australis Macleay, 1881 (Myliobatididae) collected from Norfolk Bay near Hobart, Tasmania, Australia. Heliocotyle ewingi can be distinguished readily from the only other species in the genus, Heliocotyle kartasi Neifar, Euzet et Ben Hassine, 1999, by the presence of a single pseudoseptum on each of the peripheral loculi except the posteriormost, eyespots and by the morphology of the male copulatory organ which is a short, straight sclerotised tube which lacks a sclerotised accessory piece. The generic diagnosis is revised to accommodate the new species and the anterior glands are discussed.     

Lamellodiscus (Monogenea: Diplectanidae) parasites of Dentex macrophthalmus (Teleostei: Sparidae) from the North Atlantic coast of Africa, with a redescription of L. dentexi Aljoshkina, 1984, and description of three new species

Lamellodiscus dentexi Aljoshkina, 1984, a gill parasite of Dentex macrophthalmus (Bloch), is redescribed based on new material from the northwest coast of Africa (Senegal and Morocco). Three new species of Lamellodiscus Johnston et Tiegs, 1922 from D. macrophthalmus are described, Lamellodiscus toguebayei sp. n., L. vicinus sp. n., and L. triacies sp. n., all belonging to the "ignoratus" group. They can be distinguished from all other species of this group by the size and shape of male copulatory organ and sclerotised parts of the haptor. Considering the peculiar morphology of the male copulatory organ (long and thin tube) we propose to put together L. dentexi, L. virgula Euzet et Oliver, 1967 and L. obeliae Oliver, 1973 to form the "elongatus" type within the "elegans" group.     

Dendromonocotyle colorni sp. n. (Monogenea: Monocotylidae) from the skin of Himantura uarnak (Dasyatididae) from Israel and a new host record for D. octodiscus from the Bahamas

Dendromonocotyle colorni sp. n. (Monogenea: Monocotylidae) is described from the dorsal skin surface of two specimens of Himantura uarnak (Forssk?l) kept at the Eilat Underwater Observatory in Israel. Dendromonocotyle colorni is distinguished from the other eight species in the genus by the morphology of the terminal papillar sclerite on the haptor, the distal portion of the male copulatory organ and the morphology of the vagina. The development of the male copulatory organ is detailed for D. colorni and the adaptations of species of Dendromonocotyle to life on the dorsal skin surface of rays are discussed. Dendromonocotyle octodiscus Hargis, 1955 was identified from the dorsal skin surface of the southern stingray Dasyatis americana Hildebrand et Schroeder off Bimini, Bahamas and represents a new host record.     

Revision of Dioncopseudobenedenia Yamaguti, 1965 including the description of D. ancoralis sp. n. (Monogenea: Capsalidae) from Pacific acanthuroid teleosts

Dioncopseudobenedenia Yamaguti, 1965 (Monogenea: Capsalidae) is redefined. Dioncopseudobenedenia kala Yamaguti, 1965 (type species) is redescribed from type material from Hawaii and from new specimens from Heron Island, Queensland, Australia and New Caledonia. We made detailed observations on D. macracantha Yamaguti, 1968 from type material from Hawaii, and from new material from Heron Island and New Caledonia. Dioncopseudobenedenia ancoralis sp. n. is described from the gill chamber of Siganus lineatus (Valenciennes) from Green Island and Heron Island, Australia and from New Caledonia. This study confirms that only one pair of large central sclerites is present on the haptor in Dioncopseudobenedenia species. The male copulatory organ in species of Dioncopseudobenedenia is a penis contained in a fluid-filled space (= penis canal) with weakly muscular walls. Dioncopseudobenedenia kala and D. ancoralis bear a sclerite at the tip of the penis. In D. macracantha, the structure of the penis, which has no terminal sclerite, indicates it may combine the functions of a penis and a cirrus. Dioncopseudobenedenia is compared with Calicobenedenia Kritsky et Fennessy, 1999, the other capsalid genus with a single pair of large sclerites on the haptor. The large haptoral sclerites in species of Dioncopseudobenedenia resemble accessory sclerites, whereas those of C. polyprioni Kritsky et Fennessy, 1999 resemble hamuli. Observations of oncomiracidia confirmed that the large haptoral sclerites in D. kala are accessory sclerites. Haptoral morphology suggests that different Dioncopseudobenedenia spp. employ different means of attachment. Mating behaviour was observed twice between two different pairs of D. kala specimens from Heron Island. Two preserved specimens from Nouméa, New Caledonia had structures near the dorsal vaginal pore that we interpret as spermatophores. This is the first report of spermatophores in a capsalid inhabiting the gill chamber. The geographic distribution of Dioncopseudobenedenia spp. is discussed.     

Branchotenthes octohamatus sp. n. (Monogenea: Hexabothriidae) from the gills of the southern fiddler ray, Trygonorrhina fasciata (Rhinobatidae) in South Australia: description of adult and larva

Branchotenthes octohamatus sp. n. (Monogenea: Hexabothriidae) is described from the gills of the southern fiddler ray, Trygonorrhina fasciata Müller et Henle (Elasmobranchii: Rhinobatidae), off Adelaide, South Australia. It is distinguished from the type species, Branchotenthes robinoverstreeti Bullard et Dippenaar, 2003, by producing eggs that are joined end to end forming a chain, in the morphology of the male copulatory organ that has a pronounced constriction in duct diameter between proximal and distal regions, the possession of a thin muscular layer surrounding the proximal part of the male copulatory organ and distal region of the vaginae, and by the absence of a raised process on the shaft of the hamulus. An amended generic diagnosis is provided and the reliability of sperm duct number as a generic character is discussed. The oncomiracidium of B. octohamatus is also described and is the first monogenean to be described with only eight hooklets in the larval haptor. This discovery of eight hooklets may be important for higher-level monogenean evolutionary hypotheses.     

Some aspects of the biology and life history of Bothitrema bothi (Monogenea: Bothitrematidae) from the flounder Scophthalmus aquosus (Bothidae) from New Jersey, USA

Bothitrema bothi (MacCallum, 1913), a monopisthocotylean monogenean (Bothitrematidae) found on gills and occasionally on the olfactory rosette within the nares of the bothid flounder, Scophthalmus aquosus (Mitchill, 1815), is distributed along the Atlantic coast of the USA from Woods Hole, Massachusetts to Delaware Bay. This study details aspects of the morphology, microecology and biology of the oncomiracidium, juvenile and adult. Adult worms occur almost exclusively between rakers on the first and second gill arches while juveniles occupy secondary gill filaments. Analysis of variance revealed significant arch, side and position effects. Worm attachment and position is maintained largely by suction generated by a circular seal using its 54 radially arranged accessory haptoral sclerotised elements and a marginal valve. A small anterior appendix with two marginal hooks lies dorsal to a deep anteromedian cleft in the haptor, which, together with wall muscles, creates and releases the negative pressure required for attachment. Four pairs of gland openings in the ventrolateral margins of the anterior adhesive area produce secretions for attachment. Operculate eggs with four rounded protuberances and a filament are laid individually at four-minute intervals at 22 degrees C. Hatching occurs in five days at 20 degrees C. Oncomiracidia have two pairs of eyes, with the posterior pair fused, show both positive and negative phototaxis and swim at a mean rate of 5.2 mm/s at 22 degrees C. Larvae have a circle of 16 hooks and a pair of hamulus primordia. Other accessory haptoral sclerotised structures arise de novo in juveniles after attachment to the host. These data will help to resolve more clearly the relationships of the Bothitrematidae within the Monopisthocotylea.     

Acolpenteron australe sp. n. (Dactylogyridae:Dactylogyrinae), a new species from the ureters of Percichthys trucha (Perciformes:Percichthyidae) in Patagonia (Argentina)

Acolpenceron australe sp. n. (Dactylogyridae, Dactylogyrinae) is described from ureters and renal tubules of Percichthys trucha (Cuvier et Valenciennes) (Perciformes, Percichthyidae) from Andean Patagonian lakes. The new species has a haptor with 14 hooks, with shanks comprised of two subunits. It has overlapped intercaecal gonads, male copulatory organ as a sclerotized tube with one counterclockwise coil and a J-shaped accessory piece. It differs from the other species of Acolpenteron by having a non-forked accessory piece. This is the first monogenean species described from a percichthyid host in South America.     

Revision and phylogeny of rhamnocercinae monaco, Wood et Mizelle, 1954 (Monogenoidea: Diplectanidae)

Species of Rhamnocercinae Monaco, Wood et Mizelle, 1954 are gill parasites of sciaenid fishes (Perciformes). Seven are marine species (three in the western Atlantic and four in oriental Pacific) and one is a neotropical freshwater species (Rio Doce Basin, Brazil). While the status of the subfamily may be questioned, this assemblage of species is apparently supported by several shared apomorphic and plesiomorphic characters, such as: (1) peduncular spines with anterior and posterior roots; (2) haptor laterally expanded, armed with anchors (two pairs); bars (one ventral, two dorsal); 14 hooks and haptoral accessory spines; and (3) double (nested) tubes of the male copulatory organ (MCO), directed posteriorly with the genital pore lying posterior to the MCO. The phylogenetic hypothesis for the eight known species of this clade is: (Spinomatrix penteormos (Rhamnocercoides stichospinus, Rhamnocercoides menticirrhi) Rhamnocercus oliveri (Rhamnocercus rhamnocercus (Rhamnocercus stelliferi, Rhamnocercus bairdiella, Rhamnocercus margaritae)). This hypothesis indicates that Spinomatrix penteormos represents the sister group of all remaining rhamnocercines. The resulting phylogenetic sister-group relationships support the transfer of Rhamnocercus stichospinus Seamster et Wood, 1956 to Rhamnocercoides Luque et Iannacone, 1991 as Rhamnocercoides stichospinus (Seamster et Wood, 1956) n. comb.     

Neotropical Monogenoidea. 40. Protorhinoxenus prochilodi gen. n., sp. n. (Monogenoidea: Ancyrocephalinae), parasite of prochilodus lineatus (Characiformes: Prochilodontidae) from south Brazil

The monotypic Protorhinoxenus gen. n. is proposed to accommodate a species with the following characteristics: 1) tubular sclerotised vagina, 2) vaginal pore dextrolateral, 3) ventral and dorsal anchors with undifferentiated elongate shaft and base (representing approximately 2/3 of the length of anchor), and 4) superficial and deep roots of ventral and dorsal anchors lacking. Protorhinoxenus prochilodi sp. n. is described from the gills of Prochilodus lineatus (Valenciennes) of the Represa Capivari-Cachoeira, Municipality of Campina Grande do Sul, metropolitan area of Curitiba, Paraná. Specimens of other probable new species of Protorhinoxenus are reported from Prochilodus lineatus of the Rio Paranapanema, Municipality of Salto Grande, S?o Paulo; Hoplias spp. of the Rio Dois de Fevereiro, Municipality of Antonina, Paraná, and the Rio Piraquara, metropolitan area of Curitiba, Parana; Leporinus elongatus Valenciennes of the Rio Tibagi, Municipality of Jataizinho, Parana; and Schizodon fasciatum Agassiz of the Rio Solim?es, island of Marchantaria, near Manaus, Amazonas. Protorhinoxenus appears to be a sister group of Rhinoxenus Kritsky, Boeger et Thatcher, 1988 based on the following apparent synapomorphies: 1) ventral and dorsal anchors lacking superficial and deep roots, 2) ventral and dorsal anchors with elongate shaft, and 3) male copulatory organ with counterclockwise rings.     

The status of Rhoptrobothrium Shipley et Hornell, 1906 (Cestoda: Tetraphyllidea), with redescription of the type species, R. myliobatidis, and description of three new species from two species of Aetomylaeus (Myliobatiformes: Myliobatidae) from Malaysian Borneo

As part of a metazoan parasite survey of elasmobranchs from Malaysian Borneo, specimens of Rhoptrobothrium Shipley et Hornell, 1906 were collected from the eagle rays Aetomylaeus maculatus (Gray) and Aetomylaeus niehofii (Bloch et Schneider). The type species is redescribed from its type host, and a neotype specimen is designated. In addition, three new species of Rhoptrobothrium are described: R. chongi sp. n., R. gambangi sp. n. and R. limae sp. n. Rhoptrobothrium myliobatidis conspicuously differs from the three new species in its lack of a secondary areola; R. limae is distinguished from R. chongi and R. gambangi based on its greater total length; R. chongi possesses conspicuously stalked remi, while R. gambangi possesses short remi, often folded anteriorly. Rhoptrobothrium is somewhat unusual among tetraphyllideans in its possession of a "metascolex," a character it shares with other taxa in the Thysanocephalinae (i.e., Myzocephalus Shipley et Hornell, 1906, Myzophyllobothrium Shipley et Hornell, 1906 and Thysanocephalum Linton, 1889). The morphology of the "metascolex" of Rhoptrobothrium is investigated and new terminology is suggested to standardise the names given to structures constituting a metascolex. As a result, Rhoptrobothrium is considered to possess cephalic peduncle extensions, termed remi. In Rhoptrobothrium, each remus bears, at its distal end, a primary areola, and, in the case of the three new species, also a secondary areola proximal to the primary areola. Myzocephalus and Myzophyllobothrium are tentatively considered to possess remi; the configuration of the "metascolex" of Thysanocephalum, however, is not considered homologous to the condition in the other three genera currently placed in the Thysanocephalinae.     

A new Monogenean species, Bicotyle lucknowensis sp. n. (Monogenea: Heteraxinidae), from the Indian fish, Gudusia chapra (Ham.)

A new monogenean species, Bicotyle lucknowensis sp. n. of the family Heteraxinidae, has been described from the fish, Gudusia chapra (Ham.), from Lucknow, India. The new species is characterized by the number and shape of cirral spines, presence of an unarmed vagina and details of copulatory complex and haptoral armature.     

Annulotrematoides bryconi sp. n. (Monogenea: Dactylogyridae) parasitic on Brycon cephalus (Osteichthyes: Characidae) from Brazil

Annulotrematoides bryconi sp. n. is described and illustrated from specimens collected from gills of characiform fish, Brycon cephalus (Günther, 1869), in pisciculture ponds from Pirassununga, S?o Paulo, Brazil. Diagnostic characters of the new species are the tegument of trunk showing annulations, except on the cephalic regiona, and copulatory complex comprising sclerotized male copulatory organ coiled in 1 1/2 rings. This is the first record of monogeneans parasitic on the gills of B. cephalus.     

Neotropical Monogenoidea 37. Redescription of Gyrodactylus superbus (Szidat, 1973) comb. n. and description of two new species of Gyrodactylus (Gyrodactylidea: Gyrodactylidae) from Corydoras paleatus and C. ehrhardti (Teleostei: Siluriformes: Callichthyidae) of Southern Brazil

Two new species of Gyrodactylus (Gyrodactylidae) are described from Corydoras paleatus (Jenyns) and Corydoras ehrhardti Steindachner (Callichthyidae) of Rio Piraquara, Municipality of Piraquara, near Curitiba, Paraná, Brazil: Gyrodactylus anisopharynx sp. n. and Gyrodactylus samirae sp. n. These species are unique among the known Neotropical species of Gyrodactylus by the combination of several characters. Gyrodactylus anisopharynx is characterised by having hooks with point evenly curved, toe moderately pointed, round convex heel, straight sloping shelf, superficial bar with anterolateral projections and male copulatory organ armed with two rows of spinelets. Two variants of G. anisopharynx, of distinct pharynx size, are recognised: forma "large-pharynx" and forma "small-pharynx". Gyrodactylus samirae is characterised by having hook with straight shaft, short slightly recurved point, truncate toe, trapezoidal heel, shelf slightly concave, orthogonal to shaft; anchors with relatively short superficial root; superficial bar with extremities lightly expanded; and male copulatory organ armed with two rows of spinelets. Paragyrodactyloides superbus (Szidat, 1973) is redescribed and transferred to Gyrodactylus based on examination of type and new specimens. Features previously considered as diagnostic for the genus are misinterpretations or primitive characters for Gyrodactylus spp.     

Two new species of protogyrodactylus (Monogenoidea: Dactylogyridae) from the gills of Gerres nigri (Teleostei: Gerreidae) from Senegal

Protogyrodactylus ethiopicus sp. n. and P. kritskyi sp. n. are described from the gills of Gerres nigri Günther (Gerreidae, Perciformes) captured from the estuary of the Sine-Saloum River (Senegal, West Africa). These new species differ from previously described species within the genus by a mid- or dextro-ventral vaginal opening (dextral in all other species). They are part of a morphological species group within Protogyrodactylus Johnston et Tiegs, 1922 that has the tip of the superficial root of the ventral anchor resembling a hook and two anterior projections on the anterior margin of the ventral bar. Protogyrodactylus ethiopicus differs from the remaining species in this group mainly by the morphology of the base of the male copulatory organ (MCO), which is disk-shaped, and the shape of the anterior projections of the ventral bar (round in the new species and relatively elongate in the other species of the group). The other new species, P. kritskyi, differs from all others in the same morphological group in having a MCO with a greatly expanded base that bears a heel-like subterminal sclerotization.     

Three new species of Spiniloculus (Cestoda: Tetraphyllidea) from Chiloscyllium punctatum (Elasmobranchii: Orectolobiformes) off Borneo with clarification of the identity of the type of the genus

The type species (Spiniloculus mavensis Southwell, 1925) of the previously monotypic tetraphyllidean genus Spiniloculus Southwell, 1925 is redescribed from the type material from Moreton Bay, Australia. As a consequence the identity of this species is definitively resolved. Three new species in the genus, all collected from Chiloscyllium punctatum Müller et Henle (brownbanded bambooshark), in Borneo, are described. Spiniloculus calhouni sp. n. conspicuously differs from all three of its congeners in its possession of post-poral testes. Spiniloculus fylerae sp. n. and Spiniloculus paigeae sp. n. differ from their two other congeners in that they are relatively small worms (4-6.5 and 2.2-5 mm in total length, respectively) with fewer than 30 proglottids. They can be distinguished from one another in that, while the vitelline follicles are interrupted at the level of its ovary in S. fylerae, this is not the case in S. paigeae. Furthermore, whereas the cirrus sac of the former species is pyriform, it is elongate-oval in the latter species. This brings the total number of species in the genus to four, and lends support to the suggestion that the original identity of the type host of S. mavensis as Mustelus sp. was in error. This work also extends the range of the genus to include the island of Borneo. A key to the species of Spiniloculus is provided. Morphological data generated here, using both light and scanning electron microscopy, support the suggested close affinities between Spiniloculus and Yorkeria Southwell, 1927, both of which parasitize bamboosharks.     

Three new species of Echinobothrium (Cestoda: Diphyllidea) from Indo-Pacific stingrays of the genus Pastinachus (Rajiformes: Dasyatidae)

Three new species of diphyllidean cestodes are described from stingrays of the genus Pastinachus from the Indian and Pacific Oceans. All three new species differ from all but 10 of the 36 valid species of Echinobothrium van Beneden, 1849 in that they bear lateral hooklets arranged in a continuous band across each lateral surface of the rostellum joining the groups of dorsal and ventral apical hooks, rather than arranged in distinct dorsal and ventral groups, on each side of the apical hooks. Echinobothrium nataliae sp. n. ex Pastinachus solocirostris off Borneo differs from other relatives in the following combination of characters: number of spines in each column on the cephalic peduncle, number of lateral hooklets and number of apical hooks. Echinobothrium reginae sp. n. ex Pastinachus cf. sephen off Madagascar differs from all congeners in the following combination of characters: number of hooklets and number of spines on the cephalic peduncle. Echinobothrium vojtai sp. n. from an undescribed species of Pastinachus off Borneo differs from its congeners in the following combination of characters: number of hooklets, number of apical hooks and number of spines in each column on the cephalic peduncle. The hook formula was modified to accommodate species with lateral hooklets arranged in a continuous band as follows: {(LH) AH(A)/AH(B)}, where (LH) is the total number of lateral hooklets in a band. A table of all nominal species of Echinobothrium, showing their taxonomic status, type host and locality, number of peduncle spines in a column and hook formula, is presented. Macrobothridium djeddensis and Macrobothridium sinensis are transferred to Echinobothrium. In addition, Echinobothrium deeghai is considered as a species inquirenda.     

Plectanocotyle major sp. n. (Monogenea: Plectanocotylidae), a gill parasite of Chelidonichthys obscurus (Teleostei: Triglidae) from the Mediterranean Sea

Plectanocotyle major sp. n. (Monogenea: Polyopisthocotylea: Plectanocotylidae) is described from Chelidonichthys obscurus (Bloch et Schneider, 1801) collected from the Mediterranean coasts (Tunisia and France). The new species is compared to Plectanocotyle gurnardi collected on Chelidonichthys gurnardus and the only other valid species in the genus Plectanocotyle. The new species differs from P. gurnardi by the clamp size (137 microm vs 64 microm for clamp length and 110 microm vs 60 microm for clamp width, respectively) and the length of the male copulatory organ (107 microm vs 144 microm, respectively). Species of the Plectanocotylidae seem to be characterized by an oioxenic specificity.     

Three new genera and seven new species of trypanorhynch cestodes (family Eutetrarhynchidae) from manta rays, Mobula spp. (Mobulidae) from the Gulf of California, Mexico

Three new genera of eutetrarhynchid trypanorhynch cestodes are described from Mobula spp. (Mobulidae) from the Gulf of California, Mexico. Fellicocestus mobulae gen. et sp. n. from the gall bladder of Mobula japonica (Miller et Henle) is distinguished by elongate bothria, a pars bothrialis equal in length to the pars vaginalis, masses of gland cells in the pars vaginalis and an heteromorphous armature in which hook rows arise from a central file of hooks on the bothrial surface of the tentacle and terminate in a central file on the antibothrial surface. Species of Mobulocestus gen. n. occur in the nephridial system and cloaca of rays and are characterized by two bothria, an heteroacanthous armature with hook rows beginning on the bothrial surface and terminating on the antibothrial surface, and by hooks at the beginnings of rows with an apical cavity. M. nephritidis sp. n. and M. lepidoscolex sp. n., both from the nephridial system of Mobula thurstoni (Lloyd) are differentiated by testis number and by the presence of scale-like microtriches on the tegument of the scolex of M. lepidoscolex. M. mollis sp. n., from the cloaca of Mobula thurstoni is distinguished by testis number (97-111 in M. lepidoscolex, 20-22 in M. nephriticus and 48-70 in M. mollis). Hemionchos gen. n. from the spiral valve of Mobula spp. has two bothria, an heteroacanthous armature, hook rows arising on the bothrial surface and terminating on the antibothrial surface and hooks at the beginning of rows with an apical cavity. It differs from Mobulocestus in having a distinctive basal armature and both hook files 1 and 1' on the bothrial surface, but has an additional, small, satellite hook adjacent to each hook 1'. H. striatus sp. n. from the spiral valve of Mobula thurstoni and M. japonica is differentiated by having a basal armature of closely packed arrays of small, uncinate hooks. H. mobulae sp. n. from the spiral valve of Mobula japonica and M. munkiana Notarbartolo di Sciari, differs in testis number and in having large, flattened hooks in the basal armature. H. maior sp. n., from the spiral valve of M. japonica, is larger, differing in both the number of testes and in the basal armature.     

A new species of the genus Chauhanellus Bychowsky et Nagibina, 1969 (Monogenea) from the gills of a sea fish Tachysurus dussumieri (Val.) from Andhra Pradesh, India

Chauhanellus chauhani sp. n., collected from the gills of a sea cat-fish, Tachysurus dussumieri (Valenciennes) from the Bay of Bengal, off the coast of Kakinada, Andhra Pradesh, India is described and illustrated. It differs from the related species of the genus--C. oculatus, C. flexiosus, C. australis, C. nagibinae, and C. pedunculatus--in the shape and articulation of accessory piece with cirrus and in having a crescentic posteromedian process on its dorsal bar. It has five transverse hard structures on the ventral surface of peduncular region, by which it differs from C. oculatus and C. australis the latter have 10-11 and 3 such hard structures, respectively.