This is a Hyla versicolor tadpole that was exposed to Telorchis bonnerensis cercariae, then processed chemically to preserve the tissues, make them transparent, then stain bone and cartillage. (Drew Dietrich and Kim Fitzpatrick)

Trematode metacercarial cyst

Below the tadpole's gut is a nearly round metacercarial cyst (Telorchis bonnerensis)- here it will basically rest, try to resist the tadpole's immune system, and wait for transmission to the definitive host. (Drew Dietrich and Kim Fitzpatrick)

Scanning electron micrograph of trematode metacercarial cysts, and a recently excysted adult

Here are two intact cysts, one that recently broke open, revealing an adult. These are parasites from a local stream that remain unidentified.