Aquatic Parasite Observatory

Megalobatrachonema moraveci (Richardson & Adamson, 1988)

    • Species Name: Megalobatrachonema moraveci (Richardson & Adamson, 1988)
    • Synonyms: None
    • Taxonomy: (Richardson & Adamson, 1988) Animalia, Nematoda, Secernentea, Ascaridida, Kathlaniidae, Megalobatrachonema moraveci
    • Description: "Adult stage as described by Richardson & Adamson, 1988: Oral opening triangular, surrounded by 3 distinctly separate lips. Cephalic sense organs located at end of hypodermal peduncles. Dorsal lip with 2 papillae; subventral lips each with single papilla and amphid. Inner papillae not observed. Cuticle lining inner surface of lips thickened. Anterior of esophagus bearing 3 onchia. Esophagus long and narrow,with anterior pharyngeal portion and faintly separated corpus, isthmus, and bulb. Very slight swelling at posterior of corpus. Deirids at level of corpus swelling. Esophageal bulb lacking valves. Excretory pore located at level of esophageal bulb, opening into large sinus.

      Male: Caudal end curved ventrally. Preanal musculature consisting of 52-69 muscle pairs. Pseudosucker absent. Tail short. Caudal papillae arranged as follows: 7 pairs of preanal and median unpaired papillae on anterior anal lip, 5 pairs postanal (first and third pairs lateral). Holotype and 1 paratype showing the above papillae arrangement; 2 paratypes showing variation in papillae number. In these cases the fourth postanal pair (subventral) was absent in one specimen and represented by a single papilla in the other specimen. Phasmids between third (lateral) and fourth pairs of papillae. Spicules equal and broadly alate. Gubernaculum with rounded more dorsal end and crochet hook appearance on pointed ventral end.

      Female: Vulva in posterior third of body. Vagina muscular, anteriorly directed. Uteri amphidelphic. Ovary associated with posterior uterus originating in anterior of worm, running posteriorly, flexing anteriorly, then flexing posteriorly 15-22% body length behind esophageal bulb, and continuing to level of vulva before flexing anteriorly at oviduct. Oviduct emptying into uterus; uterus flexing anteriorly to join opposing uterus at vagina. Ovary associated with anterior uterus originating near rectum, extending anteriorly to within 1-13% body length from opposing ovary flexure, flexing posteriorly, coiling back on itself once then emptying into oviduct. Oviduct flexing anteriorly at junction with uterus; uterus flexing posteriorly and merging with opposite uterus at vagina" (Richardson and Adamson, 1988).

    • Life Cycle: "Little is known about the life cycle of nematodes in the Kathlaniidae family. There is evidence of the use of possible intermediate hosts such as flies, oligocheats and others, however whether those hosts are paratenic or necessary is unclear" (Ko, 1989).
    • Sources: Richardson, J.P.M and Adamson, M.L. 1988. A New Kathlaniidae (Cosmocercoidea; Nematoda), Megalobatrachonema (Chabaudgolvanid) moraveci sp. n. from the Intestine of the Rough-skinned Newt, Taricha granulosa. Proc. Helminthol. Soc. Wash. Vol. 55, Issue 2, p. 155-159.
    • Ko, R.C. (eds). 1989. Current Concepts in Parasitology: The Challenge in Asia. Hong Kong University press, Hong Kong. p. 193.
    • APO Parasite Records: (by Life Cycle)

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Distribution Map:


  • University of Colorado Boulder