Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
Clickable Guide
Moths Butterflies Flies Caterpillars Flies Dragonflies Flies Mantids Cockroaches Bees and Wasps Walkingsticks Earwigs Ants Termites Hoppers and Kin Hoppers and Kin Beetles True Bugs Fleas Grasshoppers and Kin Ticks Spiders Scorpions Centipedes Millipedes

Upcoming Events

Photos of insects and people from the 2015 gathering in Wisconsin, July 10-12

Photos of insects and people from the 2014 gathering in Virginia, June 4-7.

Photos of insects and people from the 2013 gathering in Arizona, July 25-28

Photos of insects and people from the 2012 gathering in Alabama

Photos of insects and people from the 2011 gathering in Iowa

Photos from the 2010 Workshop in Grinnell, Iowa

Photos from the 2009 gathering in Washington

Earwig Parasite

Earwig Parasite
Richmond Hill, York Region, Ontario, Canada
August 7, 2007
Size: 84 mm
I just thought I'd share this image of a rather unusual find. I captured an earwig and kept it for a few days. It seemed to do fine until I found it dead one day. That's when I noticed something else in the jar - a roundworm.
A great number of internet sources mention that Earwigs are attacked by "two fly parasites, a roundworm parasite and a fungal disease" - but very few go on to specify the species involved.
Only after a long search did I find this article (here) which lists this parasite as a Mermis micronigrescens. Further internet searches came up with M. nigrescens, a grasshopper parasite. I'm not particularly interested in worms, just wanting to find out the name of this parasite.

Images of this individual: tag all
Earwig Parasite Earwig Parasite

Horsehair worm?
I suspect this is actually a horsehair worm. The part about the water would make this seem likely. In nature, horsehair worms drive the host into water when the worm is ready to exit. I think a nematode would be smaller, too.

Horsehair worm
Hmmm, I'm definitely not knowledgable on worms. Sorry...
Is there actually a difference between round and horsehair worms? All along I thought they describe the same type of creature. I guess not ... thanks for the correction and info.
And yes, this earwig was actually found in a curled leaf on a creek-side tree, so that also supports what you said.

When I was in Zoology
at U of Goo (you say you're a Zoology student there) we had 2 mandatory courses in invertebrate zoology and 1 in parasitology - all of which included examples of horsehair worms (Nematomorpha) and round worms (Nematoda) if I remember right. If it's still like that, you'll be getting into the juicy details sooner or later...

I'm taking Invertebrate Zoology I right now, and am enjoying it very much. Should be getting to nematodes near the end of the course. They took out parasitology as a perequisite ... but it sounds interesting nonetheless.

Comment viewing options
Select your preferred way to display the comments and click 'Save settings' to activate your changes.