They display very low host-specificity and a single parasite can infect a large range of invertebrate hosts.

[3] At different points in its life-cycle, it passes through amastigote, promastigote, and epimastigote phases; the last is particularly characteristic, and similar stages in other trypanosomes are often called crithidial.

The etymology of the genus name Crithidia derives from the Ancient Greek word κριθίδιον (krithídion), meaning "small grain of barley".

They make many mistakes by visiting nectar scarce flowers and in so doing, slowly starve to death.

It is believed that the commercial bumble bees transmitted the parasite to wild populations in some cases.

"Does Pathogen Spillover from Commercially Reared Bumble Bees Threaten Wild Pollinators?".

"Variation in gut microbial communities and its association with pathogen infection in wild bumble bees (Bombus)".