Aquatic Parasite Observatory

Zygocotyle sp. (Stunkard, 1916)

  1. Species Name: Zygocotyle sp. (Stunkard, 1916)
  2. Synonyms: None
  3. Taxonomy: (Stunkard, 1916) Animalia, Platyhelminthes, Trematoda, Echinostomida, Paramphistomidae, Zygocotyle sp.
  4. Description: "Body small to medium, elongate-oval, ventrally concave. Acetabulum ventroterminal, prolonged anteriorly, with paired posterolateral muscular projections. Pharynx with anterior sphincter and small extramural sacs, less than half as long as pharynx. Oesophageal bulb present. Caeca thick-walled, straight or very slightly undulating, extend to or almost to acetabulum. Testes indented to lobed, tandem, in midregion of body. Pars seminalis long, convoluted. Genital pore bifurcal or immediately postbifurcal. Ovary irregular oval, median, anterior to level of caecal ends and to acetabulum. Uterus intercaecal, dorsal to testes. Uterine seminal receptacle not reported. Vitelline follicles in extracaecal lateral fields from level of pharyngeal sac nearly mid-level of acetabulum. In intestine of mainly aquatic birds (several families) and, more rarely, mammals (Cervidae, Bovidae); North , Central and Shouth America, Asia, Africa. Type species Z. ceratosa Stunkard, 1916, type by original designation, syn. or Z. lunata (Diesing, 1836) Stunkard, 1916" (Bray et al., 2005).
  5. Life Cycle: The life cycle of Z. lunata uses Helisoma or Biomphalaria snails as first intermediate hosts. Cercariae emerge and encyst on any suitable substrate, and the definitive host is trophically infected (Ostrowski de Núñez et al., 2011.)
  6. Sources: Bray, R.A., Gibson, D.I., and Jones, A. 2005. Keys to the Trematoda, Vol. 2, p. 354.
  7. Ostrowski de Núñez, M., Davies, D., and Spatz, L. 2011. The life cycle of Zygocotyle lunata(Trematoda, Paramphistomoidea) in the subtropical region of South America. Revista Mexicana de Biodiversidad Vol. 82, p. 581-588.
  8. APO Parasite Records: (by Life Cycle)
      1. Host SpeciesHost Common NameSite(s) of Infection
        Helisoma trivolvisNoneGonad Tissue

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