Molecular phylogenetics and diagnosis of Anisakis, Pseudoterranova, and Contracaecum from northern Pacific marine mammals.
01 Dec 2005-Journal of Parasitology (American Society of Parasitologists)-Vol. 91, Iss: 6, pp 1413-1429
TL;DR: Phylogenetic analysis of LSU sequences revealed strong support for the monophyly of Anisakinae, Contracaecum plus Phocascaris, Pseudoterranova, and Anisakis, which is primarily consistent with previously published phenograms based on multilocus electrophoretic data.
Abstract: 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.
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TL;DR: This mitochondrial genome of Pseudoterranova azarasi provides a novel genetic markers for exploring cryptic/sibling species and host affiliations, and should have implications for the diagnosis, prevention and control of anisakidosis in humans.
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TL;DR: A new species, Raphidascaroides moraveci n.
Abstract: Nematodes of the genus Raphidascaroides Yamaguti, 1941 parasitising doradid catfishes (Siluriformes: Doradidae) in Brazil were studied based on morphological and molecular evaluation of newly collected material. A new species, Raphidascaroides moraveci n. sp., is described from the intestine of Platydoras armatulus (Valenciennes) from River Miranda, River Paraguay basin, Pantanal, Mato Grosso do Sul. The new species differs from all of the congeners in having short spicules (163-217 μm in length) representing less than 1% of the total body length and in the posterior region of cloacal opening covered by small rudimentary spines. In addition, it differs from the other congeneric species in the number and arrangement of the caudal papillae and the structure of lips and tail. Raphidascaroides moraveci n. sp. is the third species described from freshwater fishes and the second one in the Neotropical Region. New morphological data on R. brasiliensis Moravec & Thatcher, 1997 from Megalodoras uranoscopus (Eigenmann & Eigenmann) and Platydoras costatus (Linnaeus) (both new host records) from River Xingu, River Amazon basin, Para, are provided including scanning electron micrographs of taxonomically important structures. The differentiation of the new species is supported by molecular data (partial sequences of the small and large subunits of the rRNA gene).
16 citations
TL;DR: Surprisingly, a large proportion of the non-tapeworm parasites recovered were not previously reported from this fish species, the New Zealand sole (Peltorhamphus novaezeelandiae) off the coast of Otago, New Zealand.
Abstract: Despite the fact that tapeworms comprise the bulk of parasite communities of sharks in marine ecosystems, little is known about their life cycles and, more specifically, about the potential intermediate hosts they utilize as transmission routes. In the absence of morphological features required for specific identification of larval tapeworms from potential intermediate hosts, recent molecular advances have contributed to linking larval and adult parasites and, in some instances, uncovering unknown trophic links. Host-parasite checklists are often the first source of information consulted to assess the diversity and host specificity of parasites, and provide insights into parasite identification. However, these host-parasite checklists are only useful if they encompass the full spectrum of associations between hosts and parasites. A checklist of New Zealand fishes and their parasites has been published, but recent parasitological examinations of commercial fish species reveal that the checklist appears to be far from complete. We focused our current study on a comprehensive survey of macroparasites of a commercial species, the New Zealand sole (Peltorhamphus novaezeelandiae) off the coast of Otago, New Zealand. Specifically, we were expecting to recover marine tapeworms using sharks as their definitive hosts that are generally underreported in parasite surveys. The parasites recovered included tapeworms, flukes, round worms and thorny-headed worms. Surprisingly, a large proportion of the non-tapeworm parasites we recovered were not previously reported from this fish species. A discussion on the potential ecological roles played by this fish species in the transmission of parasites is included.
16 citations
Cites methods from "Molecular phylogenetics and diagnos..."
...…of the internal transcribed spacer (ITS) region of the ribosomal cistron and cytochrome oxidase subunit II (COX2) gene were amplified using primers 93 and 94 (Nadler et al., 2005), and 210 and 211 (Nadler & Hudspeth, 2000), respectively, using PCR protocols described in the respective papers....
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TL;DR: It is revealed that the sampled Hysterothylacium larval types V may represent three different species and H. deardorffovestreetorum may represent two different taxa.
Abstract: During the last decade, many morphotypes of larval forms of Hysterothylacium have been proposed; however, their boundaries are taxonomically unclear. We compare newly collected material with data available for Hysterothylacium larvae, based on genetics and morphology, in order to evaluate their relationships and simplify their classification. The previously described Hysterothylacium larval type IV, type V, and type X were found in several marine fishes from Brazil. A new Hysterothylacium larval type XV, parasitic in Elops saurus from State of Sergipe, north-eastern Brazil, was proposed based on its genetic singularity and the presence of numerous spines throughout the body. Based upon phylogenetic reconstruction using the ribosomal DNA (rDNA) ITS2 sequences along with morphological traits, the following third stage larvae were considered valid (synonyms are inside parenthesis) type III (= types VII and VIII), type V (= types VI, XII, and XIII), and type X (= type XIV). Despite the lack of molecular data, Hysterothylacium larval type II is considered as synonym of type I because of their identical morphology. The morphometry of Hysterothylacium third stage larvae proved to be weak as a diagnostic tool due to its high rates of variation. Phylogenetic reconstruction using the concatenated sequences of rDNA ITS1-5.8S-ITS2 and the mitochondrion DNA (mtDNA) cox2 revealed that the sampled Hysterothylacium larval types V may represent three different species and H. deardorffovestreetorum may represent two different taxa. Furthermore, H. deardorffovestreetorum is considered species inquirenda due to its problematic description and diagnosis which are based only on larvae. A key to Hysterothylacium larvae from marine fishes is provided.
15 citations
Cites background or methods from "Molecular phylogenetics and diagnos..."
...Phylogenetic trees were rooted using Ascaris lumbricoides Linnaeus, 1758 as outgroup based upon previous anisakid-related phylogenies (Nadler and Hudspeth 2000; Nadler et al. 2005; Borges et al. 2012; Pantoja et al. 2015)....
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...Furthermore, accurate identification of a parasite species, regardless its stage of development, is very important to understand epidemiological, biological, and ecological patterns (Mattiucci et al. 1997; 2005; 2009; Kijewska et al. 2002; Nadler et al. 2005; Zhang et al. 2007)....
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TL;DR: This is the first record of fourth larval stage and precocious adult male specimens of Hysterothylacium in an invertebrate host, as well as the firstrecord of anisakid larvae in New Zealand crustaceans.
Abstract: Previously undescribed fourth-stage larvae of anisakid nematodes were found in the haemocoel of the amphipod Paracorophium excavatum (Thomson, 1884) (Corophiidae) in New Zealand. Morphological examination by light microscopy showed that the worms belonged to a species of Hysterothylacium Ward et Magath, 1917, based on several characters including the presence of interlabia, the location of the excretory pore posterior to the nerve ring, and the characteristics of the intestinal caecum and ventricular appendix. Interestingly, several male specimens showed precocious sexual development. This is the first record of fourth larval stage and precocious adult male specimens of Hysterothylacium in an invertebrate host, as well as the first record of anisakid larvae in New Zealand crustaceans. In addition, metacercariae of two trematode species, Coitocaecum parvum and Microphallus sp., are recorded for the first time from the amphipod P. excavatum.
14 citations
Cites background from "Molecular phylogenetics and diagnos..."
...Although its taxonomic status is under review (see Nadler et al. 2005 and references therein), the nematode family Anisakidae presently includes a wide range of parasites of aquatic organisms (fish, marine mammals, piscivorous birds, and even reptiles), some of which have considerable economic or…...
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TL;DR: In this paper, the effects of adding characters and/or taxa on phylogenetic accuracy were explored using data generated by computer simulation using a four-taxon tree in the "Felsenstein zone/7".
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TL;DR: More than 260 specimens of fish, belonging to 64 species, have been searched for nematode parasites and 9 species of fish were found to be free of nematodes.
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