Sunday, September 12, 2010

Answer to Case 130

Answer: Bot Fly larvae

As Bill mentions in his comment, he tried to rear two of these larval flies to adults but they did not enter the pupation stage (the next step of development prior to the emergence of the adult). If we could have examined the adult fly, identification to the species level would have been more straight-forward. However, we can say that based on the features of the larvae, these are most likely Cuterebra spp.

In nature, these larva drop off the rodent host and pupate in the ground. They then emerge as adults.

Thank you for all of the comments on this interesting case.

1 comment:

runbare said...


Thank you for your post. I recently rescued a baby vole at 6 days old. He is now 3.5 weeks old and I just identified that he has a parasite like the one pictured in your post. (I thought it was an abscess and treated it as such, until I noticed it began to move as if it were alive and had a mind of its own.) It's located on the rear end as well, right next to his tail. I'm currently trying to locate a vet that is willing to remove the parasite.

My question is if I can not locate a vet (as it is illegal in my state to take in wild animals) will the parasite harm the vole? Will it exit on its own without harming the vole? Of course then the question is sterilizing the empty hole after the parasite has vacated.

Please advise. Thank you very much!