Identification of transferrin in Atlantic cod Gadus morhua epidermal mucus.

The previously unreported presence of transferrin in Atlantic cod Gadus morhua epidermal mucus is described. A less destructive sampling method, which may result in decreased epidermal tissue damage, is discussed.

Taxonomy and host-specificity of Gyrodactylus aideni n. sp. and G. pleuronecti (Monogenea: Gyrodactylidae) from Pseudopleuronectes americanus (Walbaum) in Passamaquoddy Bay, New Brunswick, Canada.

Wild and cultured winter flounder Pseudopleuronectes americanus (Walbaum) from Passamaquoddy Bay were surveyed for species of Gyrodactylus Nordmann, 1832. Two species were found: G. pleuronecti Cone, 1981 and G. aideni n. sp, both members of Malmberg's 'groenlandicus group'. Although the hard parts in the haptor are very similar in the two species, hamuli of G. aideni are consistently shorter than those of G. pleuronecti. The two species differed by 35 base pairs in the ITS 1, 5.8 and ITS 2 region. A BLAST search identified a variety of species of Gyrodactylus from marine fishes in the Atlantic Ocean as closest matches, indicating the 'groenlandicus group' is part of a major marine lineage within Gyrodactylus (sensu lato) that has successfully radiated among coastal percid, pleuronectid, cottid and anarhichadid fishes. Exposure experiments suggested that winter flounder is the primary host of both species of parasites and that three other pleuronectid species in the bay may potentially serve only as occasional transport hosts.

Redescription of Pseudanthobothrium hanseni Baer, 1956 and description of P. purtoni n. sp. (Cestoda: Tetraphyllidea) from different pairs of rajid skate hosts, with comments on the host-specificity of the genus in the Northwest Atlantic.

During a parasitological survey of Leucoraja erinacea, L. ocellata, Malacoraja senta and Amblyraja radiata from Passamaquoddy Bay and waters surrounding the West Isles of the Bay of Fundy, NB, Canada, seven species of cestodes were recovered. Examination of these skates revealed the presence of two distinct species of Pseudanthobothrium Baer, 1956: one was retrieved from M. senta and A. radiata, identified as P. hanseni Baer, 1956 and redescribed herein; the other was retrieved from L. erinacea and L. ocellata and differs from previously described species. The new species is described herein as P. purtoni n. sp. on the basis of the degree of apolysis, the maximum width of the strobila, the length of the cirrus-sac and the number of testes. Additionally, the distinctiveness of both species of Pseudanthobothrium is supported by the characterisation of a 643 base-pair nuclear marker, which includes most of the D2 variable region of the large subunit ribosomal DNA (LSU). The recovery of two different tetraphyllidean species, each from two different host species, challenges the oioxeny (strict host-specificity) of echeneibothriine cestodes and can be explained, at least in part, by the similarities in diet and substrate preference within each host pair.

Establishment of the onset of host specificity in four phyllobothriid tapeworm species (Cestoda: Tetraphyllidea) using a molecular approach.

A parasitological survey in the Bay of Fundy, Canada, resulted in the recovery of mature specimens from 5 species of phyllobothriid tapeworms (Cestoda: Tetraphyllidea) from 4 rajid skates: Echeneibothrium canadensis and E. dubium abyssorum specimens from Amblyraja radiata; E. vernetae and Pseudanthobothrium n.sp. from Leucoraja erinacea and L. ocellata; and P. hanseni from A. radiata and Malacoraja senta. Partial sequence data of a variable region (D2) from the large subunit ribosomal DNA (LSU) were used here to determine the host distribution of immature specimens for 4 of these 5 species (E. d. abyssorum was not included in the analyses). Immature specimens from both Pseudanthobothrium spp. were identified in the same hosts as recorded previously for mature specimens, thus suggesting that there are mechanisms that prevent the attachment of the parasite in an 'unsuitable' host species. Immature E. canadensis specimens were recovered exclusively from A. radiata, whereas immature E. vernetae specimens were recovered from L. erinacea and A. radiata, despite the latter host species not harbouring mature E. vernetae specimens. Their presence in the latter host species may be explained by host restriction or resistance, which allows the attachment of the parasites in the 'wrong' host species, but not establishment or development.

Anthobothrium lesteri n. sp. (Cestoda: Tetraphyllidea) in Carcharhinus melanopterus from Heron Island, Australia, with comments on its site, mode of attachment, reproductive strategy and membership of the genus.

Anthobothrium lesteri n. sp. in Carcharhinus melanopterus from Heron Island, Australia is described and figured. A combination of characters, namely the number of testes, a weakly laciniate strobila and mature proglottis which is conspicuously longer than wide distinguishes it from other species that appear to be consistent with van Beneden's original concept of Anthobothrium . The scolex and the peduncle are relatively small and frail when compared with the rest of the strobila and with the detached proglottis. A myzorhynchus is absent and the stalked, undivided, simple bothridia have thickened margins. Two circular areas of muscles, which resemble accessory suckers, occur in the centre of each bothridium. There is a distinct cephalic peduncle with spiniform blade-like microtriches followed by craspedote proglottides which have a posterior four-lobed velum. Apolysis is well developed and the oncosphere has a polar filament and a dense covering of spines. Comments are made on the site, the mode of attachment, an aspect of the reproductive strategy of the new species in relation to intestinal eversion in some sharks, and membership of the genus.

The potential for false-positive diagnosis of protostrongyliasis by extraction of larvae from feces.

The potential of protostrongylid first-stage larvae (L1) to survive passage through the alimentary canal of non-infected mammals was investigated. Parelaphostrongylus tenuis L1 were collected from feces of an experimentally infected white-tailed deer (Odocoileus virginianus). We utilized two red deer (Cervus elaphus) and four laboratory rats (Rattus norvegicus) which were each fed the L1 of P. tenuis. Larvae were recovered, intact and alive, from the fecal samples of all six animals. Larvae of P. tenuis, and probably of other related species, can survive passage through the alimentary canal of uninfected mammals and they can be collected from feces using the Baermann technique and other related larval extraction methods. Rain water was found to be successful in the dispersal of P. tenuis L1 from the feces of infected animals. These findings raise the possibility of ingestion of L1 and their subsequent passage, by uninfected animals. This potential for false-positive diagnosis of infection in live animals necessitates accurate interpretation of a host's infection-status. Such findings reinforce the need for a reliable method of diagnosing infections in live animals.

Geographical, seasonal, and sex dynamics of Shipleya inermis (Cestoidea: Dioecocestidae) in Limnodromus griseus Gmelin (Aves: Charadriiformes).

We recovered the cestode Shipleya inermis from 79 of 82 short-billed dowitchers, Limnodromus griseus Gmelin, collected at various locations and times along their migratory route. Previous studies that examined various aspects of the cestode's biology were limited to North America. Data collected from North and South America in the present study provide new information on the geographical and seasonal distribution of this cestode. Although prevalence of infection was high at all times of the year, mean abundance varied from season to season and was significantly higher during the winter months than in the summer, suggesting that most recruitment takes place on the wintering grounds. Sexually mature and gravid cestodes were recovered at all locations, indicating S. inermis is a ubiquitous parasite within the host's range. Shipleya inermis showed a marked tendency to occur in pairs of male and female strobila. Analysis of the patterns of occurrence suggests that S. inermis is a protogynous hermaphrodite that usually becomes regionally dioecious, possibly in response to some form of interaction between individuals.

Paraliga charadrii n. sp. (Cestoda: Dilepididae) from the semipalmated plover, Charadrius semipalmatus Bonaparte (Aves: Charadriiformes).

Paraliga charadrii n. sp. (Dilepididae) is described from the small intestine of the semipalmated plover Charadrius semipalmatus (Charadriidae) collected from the Bay of Fundy, New Brunswick, Canada. The new species is distinguished from the type species Paraliga oophorae (Belopolskaya, 1971) Belopolskaya and Kulachkova, 1973, by having 2 identical rows of rostellar hooks and fewer testes and from the more similar Paraliga celermaturus (Deblock and Rosé, 1962) Bona, 1994, by its shorter and less robust rostellar hooks (18-19 microm vs. 24-26 microm). This is the first record of a species of Paraliga in the New World. Paraliga charadrii n. sp. was present in semipalmated plovers collected on their breeding grounds in Manitoba, on staging grounds in the Bay of Fundy, during southward migration, on wintering grounds in Venezuela, and on spring staging grounds at Delaware Bay, during northward migration, suggesting that transmission is ubiquitous.

Himasthla limnodromi n. sp. (Digenea: Echinostomatidae) from the short-billed dowitcher, Limnodromus griseus (Aves: Scolopacidae).

Himasthla limnodromi n. sp. is described from short-billed dowitchers, Limnodromus griseus, from the Araya Peninsula, Venezuela, and Delaware Bay, U.S.A. Himasthla limnodromi was not found in dowitchers on the breeding grounds or on the fall staging grounds in the Bay of Fundy but reappeared in dowitchers on the wintering grounds in the fall. This suggests that H. limnodromi is acquired by the birds on arrival on the wintering grounds and then gradually disappears during the birds' northward migration in the spring. The new species has a reniform collar armed with 31 spines, with 23 in a single uninterrupted row, and 4 corner spines in overlapping pairs at each end. The cirrus sac is up to 10 times longer than the length of the acetabulum and contains a long, smooth cirrus. The vitellaria always commence posterior to the posterior end of the cirrus sac in mature specimens. The testes are found in the posterior eighth of the long, filamentous body. Himasthla limnodromi n. sp. most closely resembles Himasthla alincia, but H. limnodromi is larger in size and has an unspined cirrus and smaller eggs.