Nomimoscolex semenasae n sp (proteocephalidea: Monticelliidae), a cestode parasite of Diplomystes viedmensis (Pisces: Siluriformes) from the Patagonian region of Argentina

Nomimoscolex semenasae n. sp. is described from the primitive fish Diplomystes viedmensis (Siluriformes) from the Patagonian region of Argentina. The new species is placed in Nomimoscolex because of the cortical position of the vitelline follicles, medullary position of the testes, ovary and uterus, and having a scolex with four uniloculate suckers. N. semenasae differs from all other species in the genus by the following combination of characters: (1) apical organ absent; (2) strobila acraspedote; (3) vagina anterior or posterior to cirrus-sac and lacking a sphincter; (4) testes in one irregular layer and in two fields connected anteriorly; (5) uterine stem cortical in immature proglottides, growing from cortical stem into medullary region in mature proglottides; (6) long uteroduct; and (7) presence of spiniform microtriches on all regions of the scolex, proliferation zone and immature proglottis. This is the first record of a proteocephalidean tapeworm in D. viedmensis and in the family Diplomystidae.     

Steganoderma szidati n. sp. (Trematoda: Zoogonidae) from Galaxias maculatus (Jenyns) and G. platei Steindachner in Patagonia,Argentina

Steganoderma szidati n. sp. is described from the intestine of two freshwater fishes, Galaxias maculatus and G. platei (Galaxiidae), from Andean lakes in Patagonia, Argentina. This freshwater zoogonid species fits in the genus Steganoderma (sensu Bray, 1987) because of the length of the caeca and the position of the vitelline follicles. The new species is characterised by possesing 6-13 vitelline follicles situated between the anterior margin of the ventral sucker and the poterior margin of the testis. The gonads are in the anterior hindbody and the ovary is anterior to the right testis. The cirrus has two conspicuous spines at its distal end, and the seminal vesicle always exhibits a constriction. The excretory vesicle never reaches the level of the posterior margin of the testes.     

Monticellia ophisterni n. sp. (Cestoda: Monticelliidae) from the swamp-eel Ophisternon aenigmaticum (Synbranchiformes) from Mexico.

Monticellia ophisterni n. sp. is described from the swamp-eel Ophisternon aenigmaticum Rosen and Greenwood (Synbranchiformes: Synbranchidae) from Lake Catemaco, Veracruz, Mexico. The new species is placed into Monticellia because of the cortical position of the testes, ovary, and uterus. It differs from other Monticellia species (with the exception of Monticellia magna (Rego, Santos and Silva, 1974)) in the position of longitudinal musculature that crosses the vitelline follicles, making them paramuscular. The new species can be distinguished from M. magna--which possesses a similar number of testes (107-139), paramuscular vitelline follicles, and numerous gland cells distributed between the apex of the scolex and suckers--in the position of the genital pore (8-21% vs. 19-27%), in the presence of a weak internal longitudinal musculature, in the arrangement of the testes in the median field, and in the absence of a vaginal sphincter. This is the first proteocephalidean tapeworm reported from a synbranchid fish and the first species of Monticellia found in North America.     

<Emphasis Type="Italic">Monticellia santafesina</Emphasis> n. sp. (Cestoda: Proteocephalidea), a parasite of <Emphasis Type="Italic">Megalonema platanum</Emphasis> (Günther) (Siluriformes: Pimelodidae) in the Paraná River basin,Argentina

The proteocephalidean tapeworm Monticellia santafesina n. sp. is described from the siluriform catfish Megalonema platanum (Günther) (Siluriformes: Pimelodidae) in the Paraná River basin, Argentina. The new species is allocated to Monticellia La Rue, 1911 (Proteocephalidae: Monticelliinae) because of the cortical position of the testes, ovary, vitelline follicles and uterus, a globular scolex without a metascolex and uniloculate suckers. The new species differs from all other species of Monticellia (except for M. lenha Woodland, 1933) in possessing a vaginal canal opening anterior or posterior to the cirrus-sac. M. santafesina can be distinguished from M. lenha by the following characteristics: a larger body size; a weakly developed internal longitudinal musculature arranged in 15–35 slim bundles of muscle fibres; vitelline follicles not interrupted at the level of the cirrus-sac and vaginal canal, and with a few paramuscular and/or medullary follicles; the absence of large spinitriches on the anterior margin of the suckers; and the utilisation of Megalonema platanum (in the Paraná River basin) as its host, rather than Sorubimichthys planiceps (Spix & Agassiz) (in the River Amazon). Monticellia santafesina exhibits low values of prevalence (9%) and intensity of infection (1). Megalonema platanum was parasitised by two proteocephalidean cestodes, Rudolphiella cf. lobosa (Riggenbach, 1895) and the new species described in this paper.     

Catatropis hatcheri n. sp. (Digenea: Notocotylidae) from Heleobia hatcheri (Prosobranchia: Hydrobiidae) and notes on its life-cycle in Patagonia, Argentina

A new species of Catatropis Oghner, 1905 from a freshwater Neotropical prosobranch snail, Heleobia hatcheri (Hydrobiidae), is described. Naturally infected snails were collected from Nahuel Huapí Lake in Andean Patagonia. The characteristics of the larval stages are also presented. Experimental adults were recovered from the distal region of the intestinal caeca of chicks and ducklings and natural adults from a wild duck Anas platyrhynchos. Adults of Catatropis hatcheri n. sp. can be distinguished from all other species of the genus in having 10-12 (11) ventral glands in each lateral row, the cirrus-sac extending back to between the first third and the middle of the body, the metraterm shorter than the cirrus-sac, a previtelline field of 1,258-1,544 (1,396), vitelline follicles reach back to the anterior border of the testes with some follicles extending slightly lateral to them, only external testicular margin lobed and genital pore in median line just posterior to the intestinal bifurcation. In addition, the eggs have one filament on each pole, the rediae contain one or two mature cercariae, and the cercariae are tri-oculate, with a long tail and encyst in the environment.     

A new genus and species of proteocephalidean tapeworm (Cestoda) from Pangasius larnaudii (Siluriformes: Pangasiidae) in Southeast Asia

A new proteocephalidean cestode is described from spot pangasius, Pangasius larnaudii (Siluriformes: Pangasiidae), from Tonle Sap Lake in Cambodia and a new genus, Pangasiocestus , is proposed to accommodate it. The genus is placed in the Gangesiinae because its scolex possesses a large rostellum-like apical organ and its genital organs (testes, ovary, vitellarium, and uterus) are situated in the medulla, with some vitelline follicles paramuscular. Pangasiocestus romani n. gen. and n. sp., the type and only species of the new genus, is characterized mainly by its rosette-like scolex composed of 4 lobes bearing a small sucker in their center, and the apical part with a large, discoidal, rostellum-like apical organ devoid of hooks, by weakly developed inner longitudinal musculature formed by very few isolated muscle fibers, uneven size of testes in immature and mature proglottids, with lateral testes smaller and more dense than median ones, by very narrow lateral bands of vitelline follicles, formed usually by single follicles, and by the vagina anterior to the cirrus sac. This is the first proteocephalidean cestode from a pangasiid catfish identified to the species level (proteocephalidean cestodes from 3 Pangasius spp. reported in an unpublished account from Vietnam, misidentified as Proteocephalus osculatus (Goeze, 1782) [?= Glanitaenia osculata ], are not considered).     

Two new species of flukes (Digenea: Bucephalidae: Prosorhynchinae) from the Western Moray Gymnothorax woodwardi (Anguilliformes: Muraenidae) from off Western Australia, with replacement of the pre-occupied generic name Folliculovarium Gu & Shen, 1983

Two new species of bucephalid trematodes are described from the rectum and intestine of the western moray eel Gymnothorax woodwardi McCulloch (Anguilliformes: Muraenidae: Muraeninae) off Point Peron in Western Australia. Dollfustrema gibsoni n. sp. is distinguished by body size, a pharynx that is intertesticular and level (latero-dextrally) with the anterior portion of the cirrus-sac, an ovary positioned dextrally to the testes and slightly anterior to (in part) the anterior testis, a uterus that extends anteriorly to the vitelline follicles but not to the level of the rhynchus, and vitelline follicles that form a confluent arc anterior to the gonads. Muraenicola nom. nov. is proposed as a replacement generic name for the pre-occupied Folliculovarium Gu & Shen 1983 nec Singh & Sinha 1981. Muraenicola botti n. sp. is distinguished from its congeners by body size, the size of the cirrus-sac (relative to body size), and in possessing tegumental spines, testes that are oblique (rather than in tandem) and eight ovarian lobes. It differs further in having an intestinal caecum that extends anteriorly to the level of the vitelline follicles and in the position of the pharynx and cirrus-sac relative to each other (lateral in part) as well as to the gonads. M. botti n. sp. also lacks a metraterm. These are the first reports of these genera from fishes off Australia and from the southern hemisphere.     

Zoogonidae (Digenea) from southern Great Barrier Reef fishes with a description of Steganoderma (Lecithostaphylus) gibsoni n. sp.

Two species of the Zoogonidae are recorded from Heron Island on the southern Great Barrier Reef. Steganoderma (Lecithostaphylus) gibsoni n. sp. is described from the intestine of Abudefduf whitleyi (Pomacentridae). The new species is distinguished by the combination of the following: pedunculate ventral sucker, caeca extending well past testes, presence of two-chambered internal seminal vesicle, vitelline follicles extending only to anterior margin of testes, and testes close to ventral sucker. Zoogonus pagrosomi Yamaguti, 1939 is recorded from Lethrinus atkinsoni (Lethrinidae). This species has been recorded previously only from a sparid from Japan. A new combination, Steganoderma (Lecithostaphylus) fugus (Zhang, Qiu & Li, 1986), is made.     

Catatropis hatcheri n. sp. (Digenea: Notocotylidae) from Heleobia hatcheri (Prosobranchia: Hydrobiidae) and notes on its life-cycle in Patagonia, Argentina

A new species of Catatropis Oghner, 1905 from a freshwater Neotropical prosobranch snail, Heleobia hatcheri (Hydrobiidae), is described. Naturally infected snails were collected from Nahuel Huapí Lake in Andean Patagonia. The characteristics of the larval stages are also presented. Experimental adults were recovered from the distal region of the intestinal caeca of chicks and ducklings and natural adults from a wild duck Anas platyrhynchos. Adults of Catatropis hatcheri n. sp. can be distinguished from all other species of the genus in having 10–12 (11) ventral glands in each lateral row, the cirrus-sac extending back to between the first third and the middle of the body, the metraterm shorter than the cirrus-sac, a previtelline field of 1,258–1,544 (1,396), vitelline follicles reach back to the anterior border of the testes with some follicles extending slightly lateral to them, only external testicular margin lobed and genital pore in median line just posterior to the intestinal bifurcation. In addition, the eggs have one filament on each pole, the rediae contain one or two mature cercariae, and the cercariae are tri-oculate, with a long tail and encyst in the environment.     

Crossing barriers of zoogeographical regions: Molecular evidence of vicariance of the only cestode parasite of loaches (Cobitidae) in the Indomalayan region,Paracaryophyllaeus lepidocephali (Cestoda: Caryophyllidea), and its redescription

Tapeworms of the genus Paracaryophyllaeus Kulakovskaya, 1961 (Cestoda: Caryophyllidea) are specific parasites of loaches (Cypriniformes: Cobitoidea) and occur almost exclusively in the Palaearctic region. The only exception and example of vicariance over the borders of two zoogeographical regions is Paracaryophyllaeus lepidocephali (Kundu, 1985), an insufficiently known species described from the Indomalayan region, with uncertain generic allocation. In the present paper, the species is redescribed based on new material collected from the type host, Lepidocephalichthys guntea, in West Bengal, India. Molecular data reveal this species as a member of Paracaryophyllaeus, within which it is the most closely related to P. cf. gotoi from Misgurnus anguillicaudatus in China and Japan on the basis of large subunit of ribosomal nuclear DNA (28S rDNA). Generic position of P. lepidocephali examined herein is also confirmed by morphology including cross sections, in particular, by a small, cylindrical body, medullary testes with testicular fields crossing the anterior margin of the cirrus sac, medullary vitelline follicles, with some follicles paramuscular, a shallow common genital atrium, short vagina and uterus not extending anteriorly beyond the cirrus sac. It differs from all Palaearctic congeners but Paracaryophyllaeus vladkae Scholz, Oros and Aydogdu, 2014 by the testicular field crossing the anterior margin of the cirrus sac. It differs from P. vladkae by more anterior position of the first vitelline follicles compared to the first testes. This species is a unique example of a fish tapeworm crossing the borders of the Palaearctic and Indomalayan zoogeographical regions.     

Chaulioleptos haywardi n. gen., n. sp. (Digenea: Sanguinicolidae) from Filimanus heptadactyla (Perciformes: Polynemidae) of Moreton Bay, Australia

Here we describe the first species of sanguinicolid blood fluke (Trematoda: Digenea) from a polynemid fish. Chaulioleptos haywardi n. gen., n. sp. is described from Filimanus heptadactyla Cuvier, 1829 (Perciformes: Polynemidae), the sevenfinger threadfin from Sandgate, Moreton Bay (southeast Queensland, Australia). Chaulioleptos haywardi differs from existing sanguinicolid genera in the combined possession of the following 7 characters: 2 testes, an entirely postovarian uterus, a uterine chamber, separate genital pores, an H-shaped intestine with abbreviated anterior caeca, tegumental spines in incomplete ventro-marginal transverse rows that are continuous along the length of the body, and vitelline follicles that are tightly compacted and subsequently appear to form a solid branching mass occupying the area anterior to intestinal bifurcation and extending posteriorly to the level of the posterior margin of the anterior testis. Chaulioleptos haywardi is most closely related to Paracardicola Martin, 1960 and Adelomyllos Nolan and Cribb, 2004.     

Nomimoscolex pertierrae n. sp. (Eucestoda: Proteocephalidea), a parasite of Pseudoplatystoma corruscans (Siluriformes: Pimelodidae) in Brazil and redescription of N. sudobim Woodland, 1935, a parasite of P. fasciatum

The cestode Nomimoscolex sudobim Woodland, 1935 (Proteocephalidea) is redescribed on the basis of its type-specimens and recently collected material found in the intestine of the 'sudobim' Pseudoplatystoma fasciatum (Siluriformes: Pimelodidae) (type-host), from the Amazon River (near the type-locality). Nomimoscolex pertierrae n. sp. is described from the 'surubi' Pseudoplatystoma corruscans from the Paraná River around Porto Rico. Among fifteen known Nomimoscolex species, only N. sudobim possess a cortical uterus in combination with osmoregulatory canals some distance internal to the proglottis margins, as in N. pertierrae n. sp. N. pertierrae differs from N. sudobim, which exhibits the most similarity with the former species, in the morphology of the scolex, the size and unusual shape of microtriches (slender digitiform) on the internal and marginal regions of the suckers, and in the lower mean number of testes [(114 in N. pertierrae, ranging between 216 (recently collected material) and 240 (type-material) in N. sudobim)]. The material described as N. sudobim by Pavanelli & Rego (1992) from the intestine of P. corruscans is considered to be N. pertierrae. The utility of microtriches as characters for distinguishing between species is demonstrated in the clear differences in the shape of those of N. pertierrae and N. sudobim. The morphology of microtriches warrants more attention in future studies on the taxonomy of proteocephalidean cestodes.     

A new genus and species of cryptogonimid from Lutjanus spp. (Pisces: Lutjanidae) on the Great Barrier Reef and New Caledonia

Lobosorchis tibaldiae n. gen. and n. sp. (Digenea: Cryptogonimidae) is described from the intestine, pyloric ceca, and rectum of 2 species of Lutjanus (Pisces: Lutjanidae), Lutjanus carponotatus and Lutjanus fulviflamma, from the Great Barrier Reef, Queensland, Australia, and New Caledonia. The genus is tentatively placed in the Neochasminae and is distinguished within the Cryptogonimidae by the combination of follicular testes, oral spines, and vitelline follicles restricted to the anterior region of the body not extending posteriorly to the ventral sucker.     

Acanthostomum macroclemidis n. sp. (Digenea: Cryptogonimidae: Acanthostominae) from the alligator snapping turtle,Macroclemys temmincki

Acanthostomum macroclemidis n. sp. is described from specimens found in the intestine of an alligator snapping turtle Macroclemys temmincki from southern Mississippi. The most important diagnostic features of the new species are the general shape and proportions of the body, the position of the pharynx (relative length of the prepharynx and esophagus), the egg size, the relative length and position of the vitelline fields, and the number, shape, and size of the circumoral spines. The new species has a very elongated body (length-width ratio, 8.9-13.0:1), 26 circumoral spines, which are almost oval in shape, a long prepharynx and a very short (shorter than the pharynx) esophagus, a seminal receptacle situated between the ovary and the anterior testis, a uterus not extending posterior to the anterior margin of the ovary, a long-stemmed and short-armed excretory vesicle, and 2 anal openings. Some features of the external morphology, such as the suckers, circumoral spines, sensory papillae, tegumental spines, and morphology of the posterior end, are examined using scanning electron microscopy. A diagnosis differentiating A. macroclemidis n. sp. from some other acanthostomine digeneans is provided. Acanthostomum macroclemidis n. sp. is the first digenean reported from an alligator snapping turtle and represents the northernmost record of an acanthostomine from turtles.     

<Emphasis Type="Italic">Luciaella ivanovae</Emphasis> n. g., n. sp. (Eucestoda: Proteocephalidea: Peltidocotylinae), a parasite of <Emphasis Type="Italic">Ageneiosus inermis</Emphasis> (L.) (Siluriformes: Auchenipteridae) in Argentina

Luciaella ivanovae n. g., n. sp. (Proteocephalidea: Peltidocotylinae) is proposed to accommodate a new cestode from a siluroid fish, the manduvé Ageneiosus inermis (Linnaeus) (syn. A. brevifilis Valenciennes) (Auchenipteridae) from the Colastiné River, a tributary of the Paraná River, in Argentina. The new genus is placed in the Peltidocotylinae because it has a medullary ovary with projections into the dorsal cortex, cortical vitelline follicles and testes, a cortical uterine stem, and uterine branches penetrating the medulla and usually as far as the dorsal cortex. Luciaella can be distinguished from all other peltidocotyline genera by the following combination of characters: a quadrangular scolex with four biloculate suckers, each of which has a cap-peak-like structure situated on the anterior margin; the absence of a metascolex; vitelline follicles arranged in two lateral rows which are crescent-shaped in transverse section; testes distributed in two dorsal fields connected anteriorly and sometimes posteriorly; and a vagina which is always anterior to the cirrus-sac and overlaps the convoluted vas deferens. Filiform microtriches are present on all tegumental surfaces, with short filiform microtriches on the scolex and long filiform microtriches on the proliferation zone and on both immature and mature proglottides. The diagnosis of the Peltidocotylinae Woodland, 1934 given by Rego (1994) is amended. L. ivanovae is the fourth proteocephalidean described from A. inermis and the third recorded in this fish host from Argentina.     

Coryphogonimus aglaos n. g., n. sp. (Digenea: Prosthogonimidae) from the Australian bush rat,Rattus fuscipes (Rodentia: Muridae), with notes on other prosthogonimids from Australian mammals

Coryphogonimus aglaos n. g., n. sp. (Digenea: Prosthogonimidae) is described from the liver of the Australian bush rat, Rattus fuscipes (Rodentia: Muridae). The new genus is distinguished from other prosthogonimids by the possession of the following combination of characters: oral and ventral suckers well developed; caeca terminating in front of testes; genital pore opening dorsal to oral sucker; vitelline follicles restricted to caecal region; uterus extending posterior to testes; and uterus without an egg reservoir. A single specimen of an as yet undetermined Coryphogonimus species is recorded from the Australian water rat, Hydromys chrysogaster (Rodentia: Muridae). A new host, Sminthopsis macroura (Marsupialia: Dasyuridae), is recorded for Coelomotrema antechinomes. Attention is drawn to the apparent rarity of the six known mammal prosthogonimids.     

Trematodes from Red Sea fishes: Neohypocreadium aegyptense n. sp. (Lepocreadiidae), Fairfaxia cribbi n. sp. and Macvicaria chrysophrys (Nagaty & Abdel-Aal, 1969) (Opecoelidae)

Specimens of the marine fishes Chaetodon lineolatus (Chaetodontidae), Lethrinus nebulosus (Lethrinidae) and Acanthopagrus bifasciatus (Sparidae) were caught in the Red Sea off the coast of Sharm El-Sheikh, South Sinai, Egypt. Fifteen (75%), four (16%) and fourteen (35%) fish, respectively, were found to harbour intestinal trematodes. C. lineolatus was parasitised by Neohypocreadium aegyptense n. sp. (Lepocreadiidae), L. nebulosus by Fairfaxia cribbi n. sp. (Opecoelidae) and A. bifasciatus by Macvicaria chrysophrys (Nagaty & Abdel-Aal, 1969) Bray, 1985 (Opecoelidae). N. aegyptense n. sp. is most similar to N. chaetodoni (Mahavi, 1972), but is smaller and differs in having acinous rather than digitate ovarian lobes, vitelline follicles extending anteriorly to midway between the ventral sucker and the intestinal bifurcation and an external seminal vesicle extending posteriorly to reach the anterior margin of the ovary. The generic diagnosis of Neohypocreadium is amended. F. cribbi n. sp. resembles F. lethini Cribb, 1990, but differs in having relatively smaller gonads, cirrus-sac and eggs, and larger suckers and pharynx. M. chrysophrys, collected from its type-host and locality, is redescribed. Plagioporus saoudi Ramadan, 1985 is considered its synonym.     

Polylekithum percai n. sp. (Trematoda: Allocreadiidae) from Percichthys trucha (Perciformes: Percichthydae) in Patagonia,Argentina, and a redescription of Homalometron papilliferum (Szidat, 1956) n. comb.

Two species of Digenea are recorded from the intestine of Percichthys trucha (Percichthydae) from Patagonian water bodies. Polylekithum percai n. sp. (Allocreadiidae) is distinguished by its body size, the relative size of the suckers, the anterior extension of the vitelline fields, the number of eggs in the uterus and the different species of fish host from the two previously described species of Polylekithum. Homalometron (= Austrocreadium) papilliferum (Szidat, 1956) n. comb. is redescribed. Due to its spined tegument and the absence of a cirrus-sac, this species is considered a member of the family Apocreadiidae.     

Two new species of bucephalids (Digenea: Bucephalidae) parasitic in freshwater fishes of Argentina

Two new species of bucephalids (Digenea: Bucephalidae) were found parasitizing freshwater fishes of Argentina. Prosorhynchoides cambapuntaensis sp. n. from Salminus maxillosus (Characidae) is characterised by the tegument covered with two kinds of spines, scale-like spines anteriorly and fine spines posteriorly; uterine loops reaching the vitelline arch in the pre-oral region; and the Laurer's canal short, opening dorsally immediately posterior to the ovary. Rhipidocotyle santanaensis sp. n. from Acestrorhynchus pantaneiro (Acestrorhynchidae) is characterised by the rhynchus with two lateral projections; the testes arranged in tandem or slightly diagonal; and the vitelline follicles forming an arch in the pre-oral region.