Subject: Giant True Fly
Location: Tortuguero, Costa Rica
May 21, 2013 2:31 pm
I live in the coastal rainforest of Costa Rica and find all kinds of large and interesting bugs on a regular basis, but this was pretty impressive. I’m guessing she’s a female because there appears to be an ovipositor, but I don’t know much about Diptera. Hoping you can help!
WOW, that is some big Horse Fly in the family Tabanidae. In addition to the ovipositor, you can tell she is a female because of the spacing between her eyes. Male Horse Flies have no spacing between the eyes. You Horse Fly looks somewhat similar to the mounted image of Myiotabanus muscoideus pictured on Sciency Thoughts, and that species is found from Mexico and Guatemala according to the site. We have not been able to locate anything definite regarding the identification of your distinctly large Horse Fly, but perhaps one of our readers will have better luck.
Update: January 21, 2014
Thanks to a comment from James, we now know that this is a Giant Wood Fly or Timber Fly in the family Pantophthalmidae, genus Pantophthalmus. We located a matching photo on P-Base and on Panama Silvestre.