Aquatic Parasite Observatory

Posthodiplostomum spp. (Dubois, 1936)

    • Species Name: Posthodiplostomum spp. (Dubois, 1936)
    • Synonyms: None
    • Taxonomy: (Dubois, 1936) Animalia, Platyhelminthes, Trematoda, Strigeidida, Diplostomatidae, Posthodiplostomum spp.
    • Life Cycle: "First intermediate hosts are snails, the second intermediate host are fishes, and the definitive hosts are piscivorous birds" (Ritossa et al., 2013).
    • Description:
      1. Body distinctly bipartite; forebody flat or concave, oval, sometimes elongate or lanceolate; hindbody oval or claviform to subcylindrical. Pseudosuckers absent; holdfast organ round or almond-shaped, withcavity opening via median slit. Oral and ventral sucker feebly developed; pharynx small. Testes tandem, different in size and shape; anterior asymmetrical, lateral; posterior larger, bilobed, reniform or cordiform, sometimes twisted, with large indentation anteriorly. Ovary ellipsoidal, pretesticular, median, lateral or diagonal and tangential to anterior testis. Vitellarium in fore- and hindbody, extending to various levels in relation to ventral sucker. Copulatory bursa evaginable, with terminal or subterminal opening. Genital cone surrounded by prepuce, encloses hermaphroditic duct, which is formed at its base by union of uterus and ejaculatory duct; ejaculatory pouch absent. In Ciconiiformes. Cosmopolitan. Metacercariae of 'neascus' type in fishes. Cercariae with rudimentary alimentary system; ventral sucker rudimentary or absent; three pairs of penetration glands in posterior part of body; flame-cell formula 2[(2+2)+(2+2+2)]=20.
    • Sources: Bray, R.A., Gibson D.I., and Jones, A. 2002. Keys to the Trematoda, Vol. 1, p. 196.
      Ritossa, L., Flores, V., and Viozzi, G. 2013. Life-Cycle Stages of a Posthodiplostomum Species (Digenea: Diplostomidae) from Patagonia, Argentina. Journal of Parasitology, Vol. 99, No. 5, p. 777-780.
    • APO Parasite Records: (by Life Cycle)

  • University of Colorado Boulder