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Worms within worms: First identification of parasitic nematodes in nemerteans
Published online by Cambridge University Press: 27 October 2025
Abstract
We report the first identification of nematode parasitism in a nemertean host (Arctostemma arcticum), representing a novel host-parasite interaction in marine ecosystems. Larvae of the anisakid nematode were discovered within the rhynchocoel of A. arcticum collected from the White Sea, suggesting transmission via ingestion of infected crustaceans – a previously undocumented pathway. The nematode was identified as Phocanema bulbosum through both morphological and molecular analyses.
The presence of nematode in nemertean A. arcticum implies trophic transmission through nemertean predation on infected amphipods, supported by hoplonemertean feeding strategy. While some fish occasionally consume nemerteans, their low predation frequency suggests A. arcticum could act as a dead-end host.
This study expands the known host range of Anisakidae, though it remains uncertain whether nemerteans serve as competent hosts in the P. bulbosum life cycle. Nevertheless, the findings highlight the need to assess nemerteans’ potential influence on parasite dynamics in fisheries and aquaculture, particularly where they coexist with intermediate and definitive hosts.
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- © The Author(s), 2025. Published by Cambridge University Press
References
Ángeles-Hernández, JC, Gómez-de Anda, FR, Reyes-Rodríguez, NE, Vega-Sánchez, V, García-Reyna, PB, Campos-Montiel, RG, Calderón-Apodaca, NL, Salgado-Miranda, C, and Zepeda-Velázquez, AP (2020) Genera and species of the Anisakidae family and their geographical distribution. Animals 10, 2374. https://doi.org/10.3390/ani10122374CrossRefGoogle ScholarPubMed
Bao, M, Giulietti, L, Levsen, A, and Karlsbakk, E (2023) Resurrection of genus Phocanema Myers, 1959, as a genus independent from Pseudoterranova Mozgovoĭ, 1953, for nematode species (Anisakidae) parasitic in pinnipeds and cetaceans, respectively. Parasitology International 97, 102794. https://doi.org/10.1016/j.parint.2023.102794CrossRefGoogle ScholarPubMed
Elder, D, Klein, J, Antonelli, A, and Silvestro, D (2021) raxmlGUI 2.0: a graphical interface and toolkit for phylogenetic analyses using RAxML. Methods in Ecology and Evolution 12, 373–377. https://doi.org/10.1111/2041-210X.13512Google Scholar
Gibson, R and Moore, J (1997) Further observations on the genus Geonemertes with a description of a new species from the Philippine Islands. Hydrobiologia 365, 157–171. https://doi.org/10.1023/A:1003199031726CrossRefGoogle Scholar
Gordeev, II, Bakay, YI, Kalashnikova, MY, Logvinenko, AD, Emelianova, OR, and Sokolov, SG (2023) Genetic structure of juvenile stages of Phocanema bulbosum (Nematoda, Chromadorea: Anisakidae) parasitizing commercial fish, Atlantic cod Gadus morhua, and American plaice Hippoglossoides platessoides in the Barents Sea. Diversity 15, 1036. https://doi.org/10.3390/d15101036CrossRefGoogle Scholar
Kem, WR (1985) Structure and action of nemertine toxins. American Zoologist 25, 99–111. https://doi.org/10.1093/icb/25.1.99CrossRefGoogle Scholar
Kem, W, Soti, F, Wildeboer, K, LeFrancois, S, MacDougall, K, Wei, DQ, Chou, KC, and Arias, HR (2006) The nemertine toxin anabaseine and its derivative DMXBA (GTS-21): chemical and pharmacological properties. Marine Drugs 4, 255–273. https://doi.org/10.3390/md403255CrossRefGoogle Scholar
Mattiucci, S, Cipriani, P, Paoletti, M, Levsen, A, and Nascetti, G (2017) Reviewing biodiversity and epidemiological aspects of anisakid nematodes from the North-east Atlantic Ocean. Journal of Helminthology 91, 422–439. https://doi.org/10.1017/S0022149X1700027XCrossRefGoogle ScholarPubMed
McDermott, JJ (2001) Status of the Nemertea as prey in marine ecosystems. Hydrobiologia 456, 7–20. https://doi.org/10.1023/A:1013001729166CrossRefGoogle Scholar
McDermott, JJ (2006) Nemerteans as hosts for symbionts: a review. Journal of Natural History 40, 1007–1020. https://doi.org/10.1080/00222930600834121CrossRefGoogle Scholar
McDermott, JJ and Roe, P (1985) Food, feeding behavior and feeding ecology of nemerteans. American Zoologist 25, 113–125. https://doi.org/10.1093/icb/25.1.113CrossRefGoogle Scholar
Norenburg, J, Chernyshev, A, Kajihara, H, and Maslakova, S (2025) World Nemertea Database. Available at https://www.marinespecies.org/nemertea (accessed May 2025). https://doi.org/10.14284/459CrossRefGoogle Scholar
Rueckert, S, Chantangsi, C, and Leander, BS (2010) Molecular systematics of marine gregarines (Apicomplexa) from North-eastern Pacific polychaetes and nemerteans, with descriptions of three novel species: Lecudina phyllochaetopteri sp. nov., Difficilina tubulani sp. nov. and Difficilina paranemertis sp. nov. International Journal of Systematic and Evolutionary Microbiology 60, 2681–2690. https://doi.org/10.1099/ijs.0.016436-0CrossRefGoogle Scholar
Valentini, A, Mattiucci, S, Bondanelli, P, Webb, SC, Mignucci-Giannone, AA, Colom-Llavina, MM, and Nascetti, G (2006) Genetic relationships among Anisakis species (Nematoda: Anisakidae) inferred from mitochondrial cox2 sequences, and comparison with allozyme data. Journal of Parasitology 92, 156–166. https://doi.org/10.1645/GE-3504.1CrossRefGoogle ScholarPubMed