Abstract
The life cycle of the nematode Cosmocerca ornata (Dujardin, 1845)—a parasite of amphibians—was studied for the first time. The experimental infection of yearlings of the marsh frog Pelophylax ridibundus infected by larvae of C. ornata was performed. The development stages of parasites in the host were studied. It has been revealed that amphibians are infected with infectious larvae (J3) of nematodes in the surface-water layer by the penetration of parasites through eyes onto the conjunctiva under the lower eyelid, where the larvae undergo the third and fourth molting. Then the parasites migrate into the oropharyngeal cavity and through the digestive tract to the place of constant localization: the posterior part of the intestine. Morphological descriptions and original drawings of J3 and J4 juveniles, molting juveniles, and adults of C. ornata are given. The development stages of the juveniles are diagnosed by the body size, location of the genital primordium, and forming copulative structure. The sex of the nematodes can be identified at the third molt stage. Mature nematodes differ from juveniles by the presence of copulative organs: the vulva in adult females and spicules in adult males. The time of the development stages of C. ornata and the total life span of the parasite in the host is determined. The effect of ambient temperature on the period of development of nematodes in amphibians is established.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Notes
The description of free-living larvae is given in the work by Kirillov and Kirillova (2015).
The first two moltings of C. ornata larvae occur in water (Kirillova and Kirillov, 2015).
REFERENCES
Anderson, R.C., Nematode Parasites of Vertebrates: Their Development and Transmission, Wallingford: CABI, 2000.
Chikhlyaev, I.V., Helminths of amphibians (Amphibia) of the Middle Volga region (fauna, ecology), Extended Abstract of Cand. Sci. (Biol.) Dissertation, Moscow, 2004.
Dusen, S., Ugurtas, I.H., and Aydogdu, A., Nematode parasites of the two limbless lizards: Turkish worm lizards, Blanus strauchi (Bedriaga, 1884) (Squamata: Amphisbaenidae), and slow worm, Anguis fragilis Linnaeus, 1758 (Squamata: Anguidae), from Turkey, Helminthologia, 2010, vol. 47, p. 158.
Kirillova, N.Yu. and Kirillov, A.A., The role of marsh frog tadpoles in the realization of the life cycle of Cosmocerca ornata (Nematoda: Cosmocercidae), Parazitologiya, 2015, vol. 49, no. 1, p. 49.
Kirillov, A.A. and Kirillova, N.Yu., Influence of wintering of the marsh frog on the reproductive structure of the hemipopulation of Cosmocerca ornata (Nematoda, Cosmocercidae), Parazitologiya, 2016a, vol. 50, no. 1, p. 21.
Kirillov, A.A. and Kirillova, N.Yu., Analysis of the reproductive structure of the hemipopulation of the Cosmocerca ornata (Dujardin, 1845) (Nematoda: Cosmocercidae) in marsh frogs of different ages, Inland Water Biol., 2016b, vol. 9, no. 3, p. 310. https://doi.org/10.1134/S199508291603007X
Maguza, V.S., Helminths of amphibians in Polesye of Ukraine, Extended Abstract of Cand. Sci. (Biol.) Dissertation, Kiev, 1973.
Shul’ts, R.S. and Gvozdev, E.V., Osnovy obshchei gel’mintologii (Fundamentals of General Helminthology), Moscow: Nauka, 1970, vol. 1.
Vojtkova, L. and Moravec, F., Die nematodenlarven (Nematoda) aus den amphibian in der Tschechoslowakei, Scripta Fac. Sci. Nat. UJEP Brunensis. Biol., 1973, vol. 2, no. 3, p. 81.
Vojtkova, L., Moravec, F., and Krivanec, K., Prispevek k poznani larvalnich stadii hlistic (Nematoda) z obojzivelniku v CSSR, Folia Fac. Sci. Nat. UJEP Brunensis. Biol., 1972, vol. 36, no. 7, Helminthol. Sb. no. 1, p. 79.
Yildirimhan, H.S., Bursey, C.R., and Goldberg, S.R., Helminth parasites of the Caucasian parsley frog, Pelodytes caucasicus, from Turkey, Comp. Parasitol., 2009, vol. 76, no. 2, p. 247. https://doi.org/10.1654/4376.1
Zhdanova, T.D., 2004. Osobennosti stroeniya i povedeniya zemnovodnykh (TRANSLATION), Moscow: Mir.
ACKNOWLEDGEMENTS
We are grateful to A.A. Dobrovol’skii (St. Petersburg State University), who supervised all the researches of Cosmocerca ornata. This work would not have been performed without his support and valuable advice.
Funding
This research was performed according to the state task of the Institute of Ecology of the Volga River Basin, Russian Academy of Sciences, project no. AAAA-A17-117112040039-7 “Ecological Regularities of Sustainable Functioning of Ecosystems and Resource Potential of the Volga Basin.”
Author information
Authors and Affiliations
Corresponding author
Ethics declarations
Conflict of interests. The authors declare that they have no conflict of interest.
Statement on the welfare of animals. The experimental study was performed in accordance with the current recommended standards of the Directive of the European Parliament and of the Council of the European Union of September 22, 2010 “On the protection of Animals Used for Scientific Purposes” (EU Directive 2010/63/EU).
Additional information
Translated by I. Bel’chenko
Abbreviations: I, mean intensity; P, prevalence of infection; J1, J2, J3 and J4 – larvae of stages I–IV.
Rights and permissions
About this article
Cite this article
Kirillova, N.Y., Kirillov, A.A. Life Cycle of Cosmocerca ornata (Nematoda: Cosmocercidae), a Parasite of Amphibians. Inland Water Biol 14, 316–330 (2021). https://doi.org/10.1134/S1995082921020061
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1134/S1995082921020061