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Polystoma integerrimumThe monogenetic

trematode Michelle StanekMegan Larson

+Taxonomic Considerations

Class: monogenoidea Subclass: polystomatoinea

+Polystoma integerrimum Characteristics

Reproductive cycles are in sync between the frog and parasite due to hormones that appear in the frog’s urine

This ensures that there are a steady supply of hosts for the oncomiracidia hatchlings

Host: old world frogs

Geographic location: Europe

Size: 10mm at adult stage

Infection site: the urinary bladder of old world frogs and the gills of tadpoles

+Polystoma integerrimum Characteristics

Forms in the urinary bladder by entering through the cloaca

Where is the cloaca located?

Aka “the gill form”

Matures and reproduces on the gills until the from matures

It has gills and a functioning reproductive system (most creatures have one or the other) Think about mud puppies Is it facultative or obligatory?

Normal Neotenic

Interesting fact: P. integerrimum has TWO adult stages!

+Polystoma integerrimum The Life Cycle

+Polystoma integerrimum

(1) Hormones appearing in the frog’s urinary bladder trigger the parasite to lay eggs in the bladder

(2) The eggs are voided into the water in the frog’s spawning area.

(3) The eggs hatch into oncomiracidia in 20-50 days (depending on water temperature).

(4) The oncomiracidia will either continue to the normal adult stage or to the neotenic adult stage depending on where the tadpole is at in it’s life cycle.

Life cycle: continued

+Life Cycle: Continued

(1) The oncomiracidia attaches to the gills of the tadpole upon contact in the water.

(2) Metamorphosis occurs in the parasite leading to the development of reproductive organs.

(3) Eggs are produced by the parasite within 20-25 days and begin to hatch within 15-20 days.

(4) When the tadpole begins to mature and reabsorb its gills, the parasite will move on to the normal life cycle stage

(1) Polystoma leaves the gills and migrates on the ventral side of the tadpole to the cloaca.

(2) It enters the cloaca and migrates to the urinary bladder.

(3) Worms slowly develop for 4-5 years before production of eggs occurs during spawning season.

(4) The cycle repeats itself

Neotenic Life Cycle Normal Life Cycle

+Polystoma integerrimum The Life Cycle

+Polystoma integerrimum

The body is more narrow

Opisthaptor is not set off from the body

Intestine has fewer lateral branches

Ovary is a different shape

There is no uterus of genitointestinal canal

Neotenic Normal

+Polystoma Integerrimum

Is Polystoma Integerrimum more active during the winter or spring season? What do you think?

Period of Activity

+Polystoma integerrimum

There is no significant economical impact because the frog is not significantly effected by the parasite.

Economical impact

+Work Cited Schmidt, GD; Roberts, LS. Foundations of Parasitology.

Seventh ed. P. 306-307.

Williams, JB. Phylogeny of the Polystomatidae (Platyhelmenthes, monogea) with particular refence to

Polystoma integerrimum. International Journal of Parasitology: vol. 25:4. 1995.

http://faculty.evansville.edu/de3/b43403/PDFs/19_Monogeneans.pdf

+Pop Quiz 8^[

Would it be more or less beneficial to the parasite if the oncomiracidia hatched right away after being voided into the spawning area?

What is the active season for Polystoma integerrimum?

Why might there be two different adult life cycles for this parasite?

What does Polystoma integerrimum do if it infects humans?

If Polystoma integerrimum attaches to the gills of a tadpole, which life cycle will it go through?