Aquatic Parasite Observatory

Cosmocephalus sp. (Molin, 1858)

    • Species Name: Cosmocephalus sp. (Molin, 1858)
    • Synonyms: None
    • Taxonomy: Animalia, Nematoda, Secernentea, Spirurida, Acuarioidae, Cosmocephalus sp.
    • Description: Systematics are based mostly on complexity of cephalic organs of fixation. Cordons extend longitudinally and expand on the cervical region. Cosmocephalus sp. has cordons recurrent on lateral fields forming simple arch convex anteriorly (Anderson et al., 2009).
    • Life Cycle: Some species of Cosmocephalus utilize an indirect lifecycle where adult worms reside in birds. L1, L2, and infective L3 larvae are found in fishes and amphipods. After the intermediate host is eaten, the parasites molt into L4, L5 and adult stages of the worm inside the esophagus of a bird (Anderson and Wong, 1982).
    • Sources:Anderson, R.C., Chabaud, A.G., and Willmott, S. 2009. Keys to the Nematode Parasites of Vertebrates, Archival Volume, p. 383-387.
    • Anderson, R.C. and Wong, P.L. 1982. The transmission and development of Paracuaria adunca (Creplin, 1846) (Nematoda: Acuarioidea) of gulls (Laridae). Canadian Journal of Zoology, Vol. 60, p. 1426-1440.
    • APO Parasite Records: (by Life Cycle)
      1. Host SpeciesHost Common NameSite(s) of Infection
        Larus sp.GullEsophagus

Parasite Images:


  • University of Colorado Boulder