One of our readers recently reached out from Costa Rica. He explained that he found some worm-like organisms on the side of his toilet. At first he thought someone forgot to flush, but upon closer inspection he realized the objects were moving and therefore alive! He said he normally flushes them, but they continue to appear in the water, and he has even found some on the bathroom floor. He hopes we will be able to identify the specimens and advise him on how to get rid of them. In the first photograph he sent, it is difficult to see the specimen since it is so tiny in the toilet bowl:

When readers find worm-like organisms in their toilets, they are usually dealing with earthworms, drain fly larvae, or midge fly larvae (a.k.a. bloodworms.) After looking at this photo, we believe this isn’t any of those three. So, if it isn’t one of the usual suspects, what did our reader find? Let’s take a closer look:

We believe that this is a crane fly larva! Crane fly larvae can be tan, green, or grey. They have plump bodies with fleshy projections on their posterior ends. Over time, the larvae develop a tough outer skin, which is the reason some people call these larvae “leatherjackets.” There are over 500 species of crane fly larvae, most of which are aquatic, like the ones our reader found. Aquatic crane flies usually eat decaying vegetation and debris, but some species eat other insects. We think that the organic debris in our reader’s toilet bowl and drain is probably serving as a food source for these organisms. To get rid of them, he will need to give his toilet a thorough cleaning. He should use a cleaning agent that is designed to kill organic material and scrub out his entire toilet. (Two that we like are Bio Drain gel and Bio Clean powder.) He might also want to clean the shower and sink while he is at it, and continue to clean his bathroom every 2 weeks to prevent future crane fly larvae from showing up!

To sum up, we believe the creatures our reader found in his toilet are crane fly larvae! These larvae don’t bite, sting, or carry/transmit human diseases!

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