Shorter Cirrus Sac Research Articles

Redescription of Proteocephalus fallax La Rue, 1911 (Cestoda) and a list of proteocephalid tapeworms of whitefish (Coregonus spp.).

Tapeworms of the genus Proteocephalus Weinland, 1858 (Cestoda: Proteocephalidae) are common and widespread intestinal parasites of whitefish (Coregonus spp., Salmonidae: Coregoninae). Previous taxonomic studies, based solely on morphology and inconsistently fixed specimens, concluded that all salmoniform fish, including whitefish, are parasitised by a single euryxenous and highly polymorphic species, Proteocephalus longicollis (Zeder, 1800). However, recent molecular phylogenetic analyses have revealed the existence of several species specific to individual genera or even species of salmoniform fish. In this study, Proteocephalus fallax La Rue, 1911 is redescribed based on newly collected and genetically characterised specimens from several Coregonus species in Switzerland, the type locality of the species, and in Norway. This cestode was previously synonymised with P. exiguus La Rue, 1911, a parasite of whitefish in North America, but the two species are not closely related. Proteocephalus fallax differs from P. exiguus in its larger body size, wider proglottids, shorter cirrus sac and broader scolex. In addition, the other Proteocephalus species described in whitefish are briefly discussed, with comments on their validity, host range and distribution.

Blood flukes of Asiatic softshell turtles: revision of Coeuritrema Mehra, 1933 (Digenea: Schistosomatoidea) and a new species infecting Chinese softshell turtles, Pelodiscus sinensis (Trionychidae), from Vietnam.

Coeuritrema Mehra, 1933, previously regarded as a junior subjective synonym of Hapalorhynchus Stunkard, 1922, herein is revised to include Coeuritrema lyssimus Mehra, 1933 (type species), Coeuritrema rugatus (Brooks et Sullivan, 1981) comb. n., and Coeuritrema platti Roberts et Bullard sp. n. These genera are morphologically similar by having a ventral sucker, non-fused caeca, two testes, a pre-testicular cirrus sac, an intertesticular ovary, and a common genital pore that opens dorsally and in the sinistral half of the body. Phylogenetic analysis of the D1-D3 domains of the nuclear large subunit ribosomal DNA (28S) suggested that Coeuritrema and Hapalorhynchus share a recent common ancestor. Coeuritrema is morphologically most easily differentiated from Hapalorhynchus by having ventrolateral tegumental papillae and a definitive metraterm that is approximately 3-7× longer than the uterus. Coeuritrema comprises species that reportedly infect Asiatic softshell turtles (Testudines: Trionychidae) only, whereas Hapalorhynchus (as currently defined) comprises blood flukes that reportedly infect those hosts plus North American musk turtles (Sternotherus Bell in Gray) and mud turtles (Kinosternon Spix), both Kinosternidae, North American snapping turtles (Chelydridae), Asiatic hard-shelled turtles (Geoemydidae) and African pleurodirans (Pelomedusidae). Coeuritrema platti sp. n. infects the blood of Chinese softshell turtles, Pelodiscus sinensis (Wiegmann), cultured in the Da Rang River Basin (Phu Yen Province, Vietnam). It differs from C. lyssimus by having a narrow hindbody (< 1.6× forebody width), ventrolateral tegumental papillae restricted to the hindbody, a short cirrus sac (< 10% of corresponding body length), a transverse ovary buttressing the caeca, a short, wholly pre-ovarian metraterm (~ 10% of corresponding body length), and a submarginal genital pore. It differs from C. rugatus by having small ventrolateral tegumental papillae, testes without deep lobes, and a Laurer's canal pore that opens posterior to the vitelline reservoir and dorsal to the oviducal seminal receptacle. The new species is only the second turtle blood fluke reported from Vietnam.

A new species of Neolebouria Gibson, 1976 (Opecoelidae: Plagioporinae) from the whitecheek monocle bream, Scolopsis vosmeri (Perciformes: Nemipteridae), from the Panjim coast at Goa, with a checklist of parasites previously reported from this fish.

Neolebouria capoori n. sp. (Opecoelidae: Plagioporinae) is described from the whitecheek monocle bream, Scolopsis vosmeri (Bloch) (Perciformes: Nemipteridae) from the Panjim coast on the central west coast of India at Goa. The new species differs from both Neolebouria cantherhini (Li, Qiu & Zhang, 1988) as originally described from Thamnaconus modestus (Günther) (syn. Cantherines modestus Günther ) and Neolebouria confusum (Overstreet, 1969) as originally described from Ocyurus chrysurus (Bloch) by having the cirrus sac surpassing the ventral sucker posteriorly in N. cantherhini and being entirely preacetabular in N. confusum compared to terminating near the midlevel of the ventral sucker in N. capoori n. sp. The new species is most similar to N. confusum, but it further differs from this species by having the vitelline fields terminating near the level of the esophageal bifurcation compared to terminating near the level of the posterior margin of the pharynx, a larger sucker ratio (1:1.7-1:2.0 compared to 1:1.4-1:1.7), a somewhat shorter cirrus sac relative to body length (160-448, representing 9-18% of the body length compared to about 367, representing 22%), and the egg of the new species has a boss at the anopercular end that is not present in N. confusum. This study represents the first report on an opecoelid from S. vosmeri. A review of the parasites reported from S. vosmeri is included.

A New Species ofPodocotyloides(Digenea: Opecoelidae) from the Grey Conger Eel,Conger esculentus, in the Caribbean Sea

Podocotyloides brevis n. sp. (Digenea: Opecoelidae) is described from Conger esculentus Poey, 1861, from the Caribbean Sea, off the coast of Mayagüez, Puerto Rico. It can be separated from the other 13 accepted species in the genus by having a shorter cirrus sac, both in length and relative length. Podocotyloides brevis, with a cirrus sac length less than 10% of the body length, most closely resembles Podocotyloides dorabus Lokhande, 1990, which has a cirrus sac that is approximately 16% of the body length. It can be further differentiated from P. dorabus by having ovarian and testicular lengths greater than the oral sucker length. This is the first report of a member of this genus from the Caribbean Sea and from a host species collected as deep as 200 m. A key to the recognized members of Podocotyloides Yamaguti, 1934, is also presented.

Further reports of Acanthocolpidae Lühe, 1906 (Digenea) from fishes off New Caledonia, with descriptions of two new species

Acanthocolpus liodorus Lühe, 1906 and Stephanostomoides tenuis (Manter, 1963) are reported from Chirocentrus dorab (Forsskål) for the first time from off New Caledonia. Stephanostomum noumeaense n. sp. from Carangoides dinema Bleeker is described with an uninterrupted ring of 34-42 circum-oral spines. It differs from other species with a similar circum-oral spine number and configuration, and a similar vitelline distribution, by its short cirrus-sac, not reaching close to the vitellarium. S. paratantabiddii n. sp. from Carangoides fulvoguttatus (Forsskål) is superficially similar to S. tantabiddii Bray & Cribb, 2004, with an interrupted ring of 34-39 circum-oral spines, but differs in its short genital atrium and cirrus-sac, the armament of the ejaculatory duct and the vitelline fields being interrupted at the level of the gonads. Stephanostomum carangi Liu, 1998 from Carangoides fulvoguttatus and S. hawaiiense Yamaguti, 1970 and S. nyoomwa Bray & Cribb, 2003 from Caranx sexfasciatus Quoy & Gaimard are reported from off New Caledonia for the first time, and their measurements are given.

Re-evaluation of the species composition of Bashkirovitrema Skrjabin, 1944 (Digenea: Echinostomatidae), with the description of two new species of this genus and the proposal of Kostadinovatrema novaeguiniense n. g., n. sp.

A comparison of specimens previously identified as Bashkirovitrema incrassatum (Diesing, 1850) from the African or cape clawless otter Aonyx capensis, and the speckle-throated or spotted-throated otter Hydrictis maculicollis from the Old World with specimens and descriptions of B. incrassatum from the New World showed that those from Africa (Bashkirovitrema africanum n. sp.) had a more extensive distribution of the vitelline fields than either B. canadense n. sp. from the northern river otter Lontra canadensis and the American mink Neovison vison (North America) and B. incrassatum from the Neotropical river otter Lontra longicaudis (South America). B. africanum n. sp. further differs from B. canadense n. sp. by having a smaller body, shorter forebody, smaller oral sucker, longer cirrus, shorter intertesticular space, shorter post-testicular space and longer eggs. B. canadense n. sp. can be distinguished from B. incrassatum by having a longer body, longer forebody, smaller sucker ratio, smaller testes, greater distance between the ventral sucker and the ovary, shorter cirrus-sac, longer post-testicular space and narrower eggs. B. africanum n. sp. differs from B. incrassatum by having a smaller ventral sucker, larger ovary, shorter cirrus-sac, smaller intertesticular space, larger post-testicular space and longer eggs that are not as wide. Kostadinovatrema n. g., as represented by K. novaeguiniense n. sp., can be separated from species of Bashkirovitrema Skrjabin, 1944 by having a wider body width to length profile, a head collar that is narrower than the forebody and armed with 33 rather than 27 collar spines, an ovary that is further removed anteriorly from the testes, and a dorso-ventrally flattened hindbody that is nearly as broad as the forebody. The new genus differs from Hypoderaeum Dietz, 1909 and Moliniella Hübner, 1939 by having 33 head collar spines.

Two Cyclocoelids from the Lesser Yellowlegs, Tringa flavipes (Scolopacidae), from the Central Flyway of North America, Including the Description of Haematotrephus selfi n. sp. (Digenea: Cyclocoelidae)

Seven specimens of cyclocoelids (6 specimens representing Haematotrephus selfi n. sp. and 1 specimen representing a second unidentified species of Haematotrephus) collected by the late Dr. J. Teague Self, former professor, Department of Zoology, University of Oklahoma, Norman, Oklahoma, U.S.A., from the body cavities of 3 lesser yellowlegs, Tringa flavipes, (2 birds collected from Roger Mills County, Oklahoma on 23 and 29 August 1963, and 1 collected from Manitoba, Canada on 3 June 1964) and deposited in the Manter Laboratory of Parasitology, University of Nebraska, Lincoln, Nebraska are described. Haematotrephus selfi n. sp. can be distinguished from all other species in the genus that lack an oral sucker except Haematotrephus limnodromi by having intertesticular uterine loops. It most closely resembles H. limnodromi but differs from it by having a smaller body, a smaller pharynx, smaller testes, a shorter cirrus sac, and somewhat smaller eggs. In addition, H. selfi n. sp. lacks a uterine seminal receptacle.

Szidatitrema yamagutii n. sp. (Digenea: Cyclocoelidae: Ophthalmophaginae) from the bearded barbet, Lybius dubius (Capitionidae), and the white-necked myna, Streptocitta albicollis (Sturnidae), that died at the Audubon Zoo in New Orleans, Louisiana, U.S.A.

Szidatitrema yamagutii n. sp. was found in the air sacs and body cavities of 2 bearded barbets, Lybius dubius, and a white-necked myna, Streptocitta albicollis, that died at the Audubon Zoo, New Orleans, Louisiana between June, 2000 and April, 2005. The new species can be distinguished from Szidatitrema philomachii and Szidatitrema vogeli, the only species currently assigned to this genus, by having a smaller egg size (80–105 by 40–55 compared to 117–126 by 54–72 and 110 by 50, respectively) and the testes of S. yamagutii n. sp. are less obliquely positioned relative to each other. Szidatitrema yamagutii n. sp. further differs from S. philomachii by lacking an oral sucker and having larger testes (anterior testis 405 by 375 compared to 270 by 210; posterior testis 435 by 370 compared to 225 by 210) and from S. vogeli by having a shorter cirrus sac (345 compared to 554) ), smaller testes (anterior testis 405 long compared to 700; posterior testis 435 long compared to 500), a smaller ovary (220–330 wide compared to 400), and a larger postovarian space (approximately 10% of body length compared to 6%). This new species was likely introduced into the Audubon Zoo through the importation of species of Old World birds.

Three species of Pycnadenoides Yamaguti, 1938 (Digenea: Opecoelidae), including two new species from temperate marine fishes of Australia.

Pycnadenoides pagrosomi Yamaguti, 1938 and P. reversati n. sp. from Pagrus auratus (Sparidae) and P. invenustus n. sp. from Nemadactylus valenciennesi (Cheilodactylidae) are described from the temperate marine waters off south-west Western Australia and south-east Queensland. The difference in the anterior extent of the vitelline follicles observed in P. reversati n. sp. recovered from off south-east Queensland waters and the material from off Western Australia is discussed. P. reversati n. sp. is distinguished from P. pagrosomi mainly in the position of the genital pore and in the arrangement of the testes, and from P. invenustus n. sp. in the posterior extent of the cirrus-sac. P. reversati belongs to the group of species with a short cirrus-sac and P. invenustus to the group with the cirrus-sac reaching into the anterior hindbody.

Chimaerula bonai sp. n. (Cestoda: Dilepididae) from the bare-faced ibis, Phimosus infuscatus (Lichtenstein) (Aves: Threskiornithidae) in Paraguay.

Chimaerula bonai sp. n. is described from the small intestine of Phimosus infuscatus (Lichtenstein) in Paraguay. The new species differs from the other two species of Chimaerula Bona, 1994, i.e., Chinmaerula woodlandi (Prudhoe, 1960) and Chinmaerula leonovi (Belogurov et Zueva, 1968), mainly by the intermediate number of rostellar hooks (30-34 compared to 42-46 in the former and 20-22 in the latter), longer rostellar hooks (31-34 microm versus 26 microm and 19-21 microm, respectively), shorter cirrus sac (58-82 microm versus 158-201 microm and 134-183 microm, respectively) and the absence of rosethorn spines in the cirrus armament. Modifications in the generic diagnosis of Chimaerula are proposed in order to conform it with some peculiarities of the new species (i.e., the relatively small and thin cirrus, the absence of rosethorn spines in its armament and the small cirrus sac).

Thysanotaenia congolensis n. sp. (Cestoda: Anoplocephalidae) in the Lesser Savanna Cane Rat, Thryonomys gregorianus from Democratic Republic of Congo, Africa

Ten (100%) lesser savanna cane rats, Thryonomys gregorianus, collected from the Lake Kivv area of the Democratic Republic of Congo, Africa were found to be infected with an undescribed anoplocephalid tapeworm, Thysanotaenia congolensis n. sp. Like other species of Thysanotaenia, T. congolensis n. sp. has the ovary and vitellarium centrally located, and the egg capsules and testes are intervascular. The new species differs from the 2 existing species, Thysanotaenia lemuris in lemurs and Thysanotaenia cubensis in humans, in being smaller (34-50 mm long) and in having a smaller scolex (260-410 microns in diameter), a shorter cirrus sac (115 microns long), and smaller eggs (40 microns in diameter). Anastomoses of the excretory system and formation of egg capsules in the new species are also described.

Microsomacanthus macrotesticulata n. sp. (Cestoda: Hymenolepididae) from South African Waterfowl

Microsomacanthus macrotesticulata n. sp. is described from southern pochards, Netta erythrophthalma (Eyton), yellowbilled ducks, Anas undulata Dubois, and redbilled teal, Anas erythrorhyncha Gmelin (Anatidae) from the Republic of South Africa. The new species is armed with 10 rostellar hooks 29-32 μm long. The short cirrus sac (88-146 μm long) extends just beyond the poral excretory vessels. The length of the cirrus sac and the diameter of the testes are approximately equal in mature proglottids. The distinctive cirrus has an armed conical base that tapers to a narrow, tubular, unarmed distal region

Echinocotyle capensis n.sp. (Cestoda: Hymenolepididae) from South African waterfowl

Echinocotyle capensis n.sp. is described from Cape shovelers (Anas smithii (Hartert)) and Cape teal (Anas capensis Gmelin) collected at Barberspan, Transvaal Province, Republic of South Africa. Echinocotyle capensis is a small cestode up to 1.62 mm long with 10 rostellar hooks 50–55 μm long. It most closely resembles Echinocotyle singhi Srivastava and Pandey, 1980 but has slightly longer rostellar hooks and a shorter cirrus sac, and lacks the vaginal sphincter present in E. singhi.

Podocotyle araiisp. nov. (Digenea: Opecoelidae) fromSebastesspp. off the coast of British Columbia, with a key to the species ofPodocotyleDujardin, 1845, occurring off the Pacific coast of North America

Podocotyle araii sp. nov., from Sebastes spp. off Vancouver Island, differs from other members of the genus in that it has the following combination of features: a slender body, a short cirrus-sac containing a seminal vesicle with a single anterior loop, a sucker ratio of 1 : > 2, and an indistinctly trilobed ovary. A key is presented to the eight species of Podocotyle recognized as occurring off the Pacific coast of North America.

The family liolopidae (Digenea) including a new genus and two new species from crocodilians

Two new species of liolopid digeneans infecting crocodilians are described and the classification of the family slightly revised. Liolope copulans from the salamander Megalobatrachus japonicus in Japan actually possesses an internal rather than external seminal vesicle and tegumental spines, and the generic diagnosis is emended to include those features. Liolopids paratisitizing crocodilians are removed from Harmotrema and placed in a separate new genus characterized by the possession of a relatively short body with gonads in the posterior rather than middle third of the body. Liolopids infecting Neotropical lizards and turtles remain in Helicotrema and those parasitizing freshwater and marine snakes remain in Harmotrema. The first new species, from Alligator mississipiensis in the southeastern United States, most closely resembles the species described as Harmotrema rudolphii from a saltwater crocodile in the Philippines, but differs from it by having a shorter cirrus sac, stouter and shorter cirrus, and slightly smaller eggs; it differs from all crocodilian liolopids by possessing a more extensively folded metraterm. The second new species, from Crocodylus cataphractis in the Congo (Belgian), differs from all others in crocodilians by having a relatively larger pharynx and smaller acetabulum. Diagnoses of all crocodilian liolopids are presented. Harmotrema laticaudae, previously known from Laticauda laticaudata in Okinawa only, is reported from Aipysurus laevis, Hydrophis major, and a ‘black and white-ringed sea snake’ in Queensland, Australia.