Aquatic Parasite Observatory

Manodistomum  syntomentera (Stafford, 1905)

    • Species Name: Manodistomum syntomentera (Stafford, 1905)
    • Synonyms: Zeugorchis syntomentera (Ingles, 1933)
    • Taxonomy: Animalia, Platyhelminthes, Trematoda, Plagiorchiida, Plagiorchiidae, Manodistomum syntomentera
    • Life Cycle: "The eggs of Zeugorchis syntomentera are em-bryonated when laid and hatch only when fed to snails (Physa gyrina) in which they develop into xiphidiocercariae. These encyst on the tadpoles of Hyla regilla and continue to develop on being eaten by garter-snakes. The adults occur in the mouth and oesophagus of the snake" (Ingles, 1933).
    • Description:
      1. "Length (permanent mount) 1.15, breadth 0.399. Mouth sucker 0.184 x 0.189. Ventral sucker small, about 0.107 in centre of body. Pharynx small, immediately behind mouth sucker. Oesophagus 0.23 long, narrow. Caeca twice as long as oesophagus, falling some distance short of posterior end. Excretory bladder broad and long, forking at the middle of the length of the coeca not far behind the ventral sucker. Immature, but parts of the genital organs represented by rudiments. Testes small, globular bodies, in a line with but behind the ends of the coeca, dividing the space between these and the end of the worm. They are lateral and parallell and give off fine ducts anteriorly. Ovary crowded between ventral sucker and the fork of the excretory bladder. Genital pore in the short space between the ventral sucker and the fork of the intestine, with the end organs of the genital ducts faintly outlined. No recognizable vitellaria.
    • Sources: Zoologischer Anzeiger, Vol. 28, p. 682.
      Dalzell, B.J. 1998. Possibilities of Manodistomum syntomentera as a cause of deformities in Rana pipiens. UW-La Crosse Journal of Undergraduate Research (JUR), Vol. I, p. 28-32.
      Ingles, L.G. 1933. Studies on the structure and life-history of Zeugorchis syntomentera Sumwalt, a trematode from the snake Thamnophis ordinoides from California. University of California Publications in Zoology, Vol. 39, No. 7, p. 163-178.
    • APO Parasite Records:

Parasite Images:

Distribution Map:

  • University of Colorado Boulder