Kalicephalus subulatus Molin, 1861, collected in Nicaragua and Chiapas, Mexico, from Constrictor constrictor imperator is reported and observations made on the morphology and reproduction in this nematode.
We present a novel case of an intestinal cestode infection in a southern sea otter (Enhydra lutris nereis). The cestode species Diphyllobothrium tetrapterum (syn. Diplogonoporus tetrapterus) was confirmed genetically. Stable isotope analysis of whiskers collected from the sea otter did not confirm the consumption of fish as the route of exposure.
Parasitism of the respiratory system is a relatively common finding in stranded cetaceans; however, no systematic investigations regarding the severity, distribution, and clinical consequences of these infections in bottlenose dolphins Tursiops truncatus have been conducted previously. The present study determined the prevalence of lungworm infections in dead stranded (n=22) and live bottlenose dolphins (n=44) from southwestern Florida, USA, during the period from 2003 to 2005. Dead stranded bottlenose dolphins were necropsied and lungs were examined visually, by palpation, and histologically for lesions consistent with verminous pneumonia. When present, nematodes were counted, measured, and identified to species based upon their morphology. Dolphin feces and blowhole swabs were collected and examined for nematode larvae. Lungworm prevalence was 77% in dead animals (n=22). The lesions in most cases were mild, chronic, and not the primary cause of death. Only 13% of dead animals examined had patent infections, with larvae present in blowhole and fecal cytology, and only 18% of animals had intact worms present at necropsy, with a geometric mean intensity of infection of 22.6 worms animal(-1). Intact worms were identified as either Halocercus lagenorhynchi or Skrjabinalius cryptocephalus. The highest prevalence of active infections was found in neonates and calves, including 1 stillborn calf. For free-ranging animals, all blowhole swabs (n=44) were negative, and fecal cytology (n=22) showed a 3% prevalence of patent infection. Findings from the present study support the theory that bottlenose dolphins can be infected transplacentally by lungworms. The impact that such infections may have on neonatal survival is unknown; however, these infections could increase neonatal mortality.
Blocks of frozen lungs of 2 Australian fur seals (Arctocephalus pusillus doriferus Wood Jones, 1925), 2 New Zealand fur seals (A. forsteri [Lesson, 1828]), and 1 sub-Antarctic fur seal (A. tropicalis [Gray, 1872]) from 3 different locations (Australia, New Zealand, and South Africa, respectively) were examined and found to contain lung parasites. This represents the first thorough description and identification of a new species, Parafilaroides normani, from an eared seal (Otariidae) in the Southern Hemisphere. The new species is described, illustrated, and differentiated from the 6 recognized species in the genus by body size, spicule shape and size, vulva to anus length, and vaginal sphincter musculature.
Cetitrema meadi sp. it. (Ttematoda: Nasitrematinae), a livei fluke front Gervais' beaked whale (Mesoplodon europaeus). is described. This species is easily distinguished from the one other member of the genus by the size and shape of body and testes. Lecithodesmus spinosus, Margolis and Pike. 1955. described from the bile ducts Balaenoptera physalus, is transferred to the genus Brachycladium, e.g., Brachyladim spinosus (Margolis and Pike, 1955) n. comb., and is reported as a new host record from the sperm whale (Physeter macrocephalus Linnaeus, 1758). Additional new host and distribution records are reported for the liver flukes. Oschmarinella sobolevi Skrjabin, 1947, Brachycludium pacificum (Dailey and Perrin, 1973) Gibson, 2005, and Brachycladium sp.. from 3 species of cetaceans. Mesoplodon europeaeus, Globicephola macrorhynchus, and Ziphius cavirostris, respectively.
Two species of hookworms (Uncinaria lucasi and Uncinaria hamiltoni) have been formally described from pinnipeds, but dissimilar types are noted from these hosts. This report is the first description of hookworms (Uncinaria spp.) from the New Zealand sea lion, Phocarctos hookeri. The nematodes were collected from dead pups on Enderby Island (Auckland Islands, 50°30', 166°17') during January and February, 2004. Standard measurements of male and female hookworms were obtained, providing a general morphometric characterization of the hookworm species in P. hookeri. Considerable variations in the body length of adult hookworms were noted within the same host. The arrangement of some of the bursal rays differs from that described for U. lucasi and U. hamiltoni.
The lungs of a northern elephant seal, Mirounga angustirostris (Gill, 1866), and Pacific harbor seal, Phoca vitulina richardii (Gray, 1864), from the eastern central Pacific, central California coast, were examined for parasites. This represents the first thorough description and identification of Parafilaroides species from northern elephant seals and Pacific harbor seals on the west coast of North America. From this study, 2 new species of Filaroides (Parafilaroides) are described, illustrated, and differentiated by shape of vaginal sphincter, body morphometrics, and spicule shape from the 4 existing, recognized species in the subgenus. In addition, the subgenus Parafilaroides is proposed to be reestablished to full generic status in the Filaroididae based on the presence of caudal papillae and DNA.
A stranded yearling male California sea lion was admitted to a rehabilitation center June 2003. On presentation, the sea lion was emaciated and had diarrhea and neutrophilia. Two weeks later, the animal became anorexic, blood and mucus were observed around the oral cavity, and corneal opacity was noted in the right eye. Hematology results at that time included leukocytosis consisting of neutrophilia with a left shift, anemia, and thrombocytopenia. Despite supportive care, the sea lion died. On post mortem examination, there were multiple areas of hemorrhage scattered throughout all lung lobes, and pulmonary blood vessels were occluded by fibrin thrombi. Nematodes identified as immature forms of Otostrongylus circumlitus were found in the right ventricle and pulmonary arteries. Histologic findings in the lungs included severe suppurative and necrotizing arteritis with vascular thrombosis, interstitial pneumonia, and large areas of pulmonary hemorrhage. This report of O. circumlitus infection in a California sea lion (Zalophus californianus) might indicate a potentially new host-parasite association.
Individual specimens of Anisakis, Pseudoterranova, and Contracaecum collected from marine mammals inhabiting northern Pacific waters were used for comparative diagnostic and molecular phylogenetic analyses. Forty-eight new sequences were obtained for this study of 14 Anisakis taxa, 8 Pseudoterranova taxa, 4 Contracaecum taxa, and 4 outgroup species. Partial 28S (LSU) and complete internal transcribed spacer (ITS-1, 5.8S, ITS-2) ribosomal DNA was amplified by the polymerase chain reaction and sequenced. Sequences of ITS indicated that Pseudoterranova specimens from Zalophus californianus (California sea lion), Mirounga angustirostris (northern elephant seal), Phoca vitulina (harbor seal), Enhydra lutris (sea otter), and Eumetopias jubatus (Steller's sea lion) exactly matched P. decipiens s. str., extending the host and geographic range of this species. Anisakis from northern Pacific marine mammals were most closely related to members of the A. simplex species complex. Comparison of Anisakis ITS sequences diagnosed the presence of A. simplex C in 2 M. angustirostris hosts, which is a new host record. Anisakis specimens from Phocoena phocoena (harbor porpoise), Lissodelphis borealis (Pacific rightwhale porpoise), and E. jubatus included 3 ITS sequences that did not match any known species. Contracaecum adults obtained from Z. californianus were most closely related to C. ogmorhini s.l. and C. rudolphii, but ITS sequences of these Contracaecum specimens did not match C. ogmorhini s. str. or C. margolisi. These novel Anisakis and Contracaecum ITS sequences may represent previously uncharacterized species. Phylogenetic analysis of LSU sequences revealed strong support for the monophyly of Anisakinae, Contracaecum plus Phocascaris, Pseudoterranova, and Anisakis. Phylogenetic trees inferred from ITS sequences yielded robustly supported relationships for Pseudoterranova and Anisakis species that are primarily consistent with previously published phenograms based on multilocus electrophoretic data.
In the present study, a new biological species of Anisakis Dujardin, 1845, was detected in Kogia breviceps and K. sima from West Atlantic waters (coast of Florida) on the basis of 19 (nuclear) structural genes studied by multilocus allozyme electrophoresis. Fixed allele differences at 11 enzyme loci were found between specimens of both adults and larvae of the new species and the other Anisakis spp. tested. Reproductive isolation from A. brevispiculata Dollfus, 1968 was demonstrated by the lack of hybrid or recombinant genotypes in mixed infections in K. breviceps. Genetic distance of the new species from its closest relative, A. brevispiculata, was D Nei =0.79. The new species is morphologically different from the other species which have been genetically characterised and from the other Anisakis retained by Davey (1971) as valid or as species inquirendae: the name of Anisakis paggiae n. sp. is proposed for the new taxon. Anisakis Type II larvae (sensu Berland, 1961) from the European hake Merluccius merluccius in the northeastern Atlantic Ocean (Galician coast) and from the scabbard fish Aphanopus carbo in Central Atlantic waters (off Madeira), were identified as A. paggiae n. sp. Its genetic relationships with respect to the seven species previously characterised (A. simplex (Rudolphi, 1809) sensu stricto), A. pegreffii Campana-Rouget & Biocca, 1955, A. simplex, (A. typica (Diesing, 1860), A. ziphidarum Paggi et al., 1998, A. physeteris Baylis, 1923 and A. brevispiculata) were also inferred. Overall, a low genetic identity was detected at allozyme level between the eight Anisakis species. Interspecific genetic identity ranged from I Nei =0.68, between the sibling species of the A. simplex complex, to I Nei =0.00 (no alleles shared at the considered loci) when A. physeteris, A. brevispiculata and the new species were compared with the other species of the genus. Concordant topologies were obtained using both UPGMA and NJ tree analyses for the considered species. In both analyses, A. paggiae n. sp. clustered with A. brevispiculata. They also indciated two main clades, the first including A. physeteris, A. brevispiculata and A. paggiae n. sp., the second containing all of the remaining species (i.e. A. simplex (s.s.), A. pegreffii, A. simplex, A. typica and A. ziphidarum). A deep separation between these two main Anisakis clades, also supported by high bootstrap values at the major nodes, was apparent. This is also supported by differences in adult and larval morphology, as well as with respect to their main definitive hosts. A morphological key for distinguishing adult A. paggiae n. sp., A. physeteris and A. brevispiculata is presented. Allozyme markers for the identification of any life-history stage of the Anisakis spp. so far studied, as well as ecological data on their definitive host preferences and geographical distribution, are updated.
Almost all (if not all) groups of marine animals including the various invertebrates and vertebrates are hosts to parasites. Parasites of these groups have been discussed by various authors in the four volumes edited by Kinne (1980-1985). This chapter is restricted to discussions of parasitic infections of the more important groups. Marine parasites are of very great ecological importance, as suggested by their great diversity, and by their often high prevalences and intensities of infection. However, very little is known about how they affect host populations in the oceans. An exception is the long-term study of salmon lice on Atlantic salmon not only in aquaculture but also in wild salmon populations, conducted because of the great economic importance of salmon. Mass mortalities caused by parasites have not been well documented for marine fish and invertebrates because of the large spaces in the oceans involved and the difficulties in monitoring such effects. Effects on marine birds are little understood and need much further study: mass mortalities of seabirds have been attributed to several causes but parasite examinations which could have revealed the role of parasites in the mortalities were not conducted. Effects on mammals such as whales are well documented, and hundreds of parasite species of mammals have been described; nevertheless, much needs to be done in this area as well. Much greater effort has gone into the study of parasite diseases in aquaculture, which is not surprising in view of the enormous and rising economic value of aquacultured fish, molluscs and crustaceans, estimated at many billions (109) of dollars annually. For example, the commercial value of cultured salmonid fishes alone in 2001 was around US$3.84 billion (US$7.44 billion for all finfish). Disease, and much of it resulting from parasites, is the single most important factor threatening the aquaculture industry. Beside these important negative aspects of marine parasites, this chapter also discusses a more positive aspect of parasites: the use of parasites in pollution monitoring. Pollution may affect the composition of parasite communities, and some parasites store certain pollutants to a higher degree than their hosts; both these phenomena can be used for monitoring pollution.
A new species of digenetic trematode and 2 species of ectoparasites from Zalophus wollebaeki Silvertsen, 1953 (Carnivora: Otariidae) in the Galapagos Islands, Ecuador, are reported. These include an eye fluke of Philophthalmus Looss, 1899 (Echinostomata: Philophthalmidae) as well as, to our knowledge, the first report of Antarctophthirus microchir (Trouessart and Neumann, 1888) Enderlein, 1906 (Arthropoda: Anoplura) and Orthohalarachne diminuata (Doetschman, 1944) Newell, 1947 (Arthropoda: Acarina) from this host and location. Philophthalmus zalophi n. sp. differs from the 4 other marine species of Philophthalmus (P. andersoni Dronen and Penner, 1975; P. burrili Howell and Bearup, 1967; P. hegeneri Penner and Fried, 1963; and P. larsoni Penner and Trimble, 1970) by its mammalian host, large body size, lack of tegumental spines, posterior length of seminal vesicle, placement of genital pore, size ratio of oral sucker to acetabulum, shape and size of testes, and size ratio of ovary to testis.
Poultry production is an important economic activity on inhabited islands of the Galápagos archipelago. There has been a recent surge in both small-scale backyard chickens and larger scale broiler production associated with growth in the human population and the tourist industry. With increased poultry production, concerns have been expressed about the increasing risk of transfer of disease from chickens to native Galápagos bird species that may have little resistance to introduced pathogens [Wikelski, M., Foufopoulos, J., Vargas, H., Snell, H., 2004. Galápagos birds and diseases: invasive pathogens as threats for island species. Ecology and Society 9(5). Available from: URL:http://www.ecologyandsociety.org/vol9/iss1/art5]. This study evaluates risks posed by chicken disease to endemic and native Galápagos bird species, based on empirical evidence of pathogens present in chickens on the islands and a literature review of effects of these pathogens in wild species. Pathogens identified in domestic chicken populations of immediate avian conservation concern are Newcastle disease, Mycoplasma gallisepticum, and the proventricular parasite Dispharynx sp. Newcastle disease (avian paramyxovirus-1) poses an imminent threat to Galápagos penguins (Spheniscus mendiculus), flightless cormorants (Phalacrocorax harrisi), and lava gulls (Larus fuliginosus), species with very small population sizes (less than 1500 animals each). Additionally, litter from broiler farms could affect ecological processes in local ecosystems. Improved poultry biosecurity measures are urgently needed on the Galápagos Islands for avian disease management, yet developing these strategies presents political, social, and economic challenges.
Heterophyopsis hawaiiensis n. sp. (Digenea: Heterophidae) is described from the ileum and colon of the endangered Hawaiian monk seal, Monachus schauinslandi. An 11-mo-old juvenile female M. schauinslandi found dead on Eastern Island of Midway Atoll, Northwestern Hawaiian Islands, U.S.A., contained approximately 7,000 specimens of this species. The new species differs from existing Heterophyopsis species in having a trilobed ovary, testes slightly oblique, and vitellaria reaching posterior of the body. This is the first report of the genus Heterophyopsis found in both a marine mammal and in the central Pacific region.
Meningoencephalitis caused by aberrant trematode migration is described in two California sea lions (Zalophus californianus) admitted to a rehabilitation hospital between May and August 2001. Both animals displayed seizure activity and were euthanized due to poor response to therapy. Gross abnormal findings included liver flukes (Zalophotrema hepaticum) in the bile ducts and areas of swelling and necrosis in the cerebrum, cerebellum, and brain stem. Histopathology revealed meningoencephalitis with necrosis, hemorrhage, and many trematode eggs within the brain. In one sea lion, an adult trematode was found on the surface of the cerebrum. These are believed to be the first reported cases of meningoencephalitis caused by aberrant trematode migration in pinnipeds.
From October 1997 to May 2001, the gastrointestinal tracts from 162 beach-cast southern sea otters Enhydra lutris nereis were examined for helminth parasites and associated lesions. Carcasses were collected opportunistically in central California between Pt. San Pedro and Pt. Arguello. The primary goals of this study were to examine spatial and temporal variability in mortality due to parasite infection, identify factors associated with increased risk of infection, and illustrate the process of intestinal perforation by Profilicollis spp. Two genera and 4 species of acanthocephalans (Profilicollis altmani, P. kenti, P. major, Corynosoma enhydri) were found in 46.3% (Profilicollis spp.) and 94.4% (C. enhydri) of the carcasses examined. Three species of Digenea (Microphallus pirum, M. nicolli, Plenosoma minimum) were found in 47% of carcasses, at times in massive numbers (> 3000 per cm2). This is the first report of the latter 2 species from the sea otter. Mortality resulting from infection by Profilicollis spp. occurred in 13.0% (n = 21) of sampled carcasses, either directly, due to perforation of the intestinal wall and peritonitis (9.9%, n = 16), or indirectly, due to inhibition of host nutrient uptake or depletion of host energy reserves to fight chronic infections (3.1%, n = 5). The most massive infections (< 8760 parasites), and all cases of intestinal perforation occurred in carcasses infected by P. altmani and/or P. kenti. Mortality due to infection by Profilicollis spp. occurred more frequently among juvenile and old-adult females (chi2 = 17.479, df = 9, p = 0.045) from sand and mixed habitats in Monterey and Santa Cruz in the north of the sea otter range (chi2 = 9.84, df = 4, p = 0.045). Spatial differences in sea otter mortality coincided with the relative distributions of Profilicollis altmani, P. kenti, and P. major, and may reflect differences in sea otter diet, or differences in intensity of infection in intermediate hosts. Mortality rate due to infection by Profilicollis spp. decreased between 1998 and 2001, though differences were not significant (chi2 = 3.983, df = 3, p = 0.40), and may vary on multi-year cycles due to environmental factors such as density of definitive hosts (e.g. the surf scoter Melanitta perspicillata), or El Niño. Corynosoma enhydri did not cause significant damage to the intestine of the host, even when present in great numbers.
Demodex phocidi n. sp. is described (all life stages) from a captive Atlantic harbor seal, Phoca vitulina, from Seward, Alaska. This is the first description of a demodecid hair follicle mite from the earless seal family Phocidae. The mites reside in the sebaceous glands of the hair follicles and are associated with persistent areas of hyperkeratosis.
Galactosomum stelleri sp. n. (Trematoda: Heterophyidae), a new trematode from the small intestine of the Steller's or northern sea-lion Eumetopias jubatus is described. An adult female specimen of E. jubatus collected from Indian Beach, Oregon, U.S.A., harbored over 100 specimens of these trematodes. The new species most closely resembles Galactosomum ubelakeri (Dailey, 1969) Pearson, 1977, and Galactosomum humbargari Park, 1936 but differs in body shape and size, lack of tegumental spines, length of esophagus, and ventral genital complex configuration. This is the third report of a species of Galactosomum from a marine mammal.
We redescribe the camallanid nematode Serpinema octorugatum (Baylis, 1933) from the box turtle Cuora amboinensis (Daudin) collected in Malaysia. In this redescription, we amend the original description by noting that there are only four cephalic papillae and that there are five pairs of post-anal papillae, and propose that the name of this species be corrected from S. octorugatus to S. octorugatum. Additionally, we removed the tissues overlying the buccal capsule and have used SEM studies to show that the peribuccal shields extend laterally from the buccal capsule, forming a surface possibly used in muscle attachment. Furthermore, we show that the supposedly non-cuticularised cylinder connecting the buccal capsule to the oesophagus in the Camallanidae is part of the buccal capsule and is, therefore, likely to be cuticularised. We also examine morphological measurements of taxonomic interest for correlations with total body length and find that many characters traditionally used for inter- and intra-specific comparisons are correlated with total body length in adult female worms. This suggests that comparisons between samples of adult female worms that do not account for the potential effect of total body length may be misleading. However, we show that some features of taxonomic interest are not correlated with total body length.
An infestation by the parasitic copepod Pennella balaenopterae was found in a stranded, 8-mo-old, female northern elephant seal (Mirounga angustirostris). Diagnosis was based on the finding of the cephalothoraxes of 14 adult female copepods from three subcutaneous sites. Bacteria cultured from lesion exudate included Arcanobacterium phocae, Escherichia coli, Edwardsiella tarda, an Enterococcus sp., and Proteus mirabilis. The lesions were drained and irrigated with chlorhexidine, and the seal was treated with a subcutaneous injection of ivermectin. The seal recovered and was released after 43 days.