Botflies and new friends

What fun it is to be alive! And what fun it is to have a pal like Brent McGregor. Every time I hear from Brent he has something to tell me I din't know, or something to show me I've never seen. This time it was another of his astonishing macro photos, asking, "What is it?"

Look at that photo! It's so sharp it looks like the fly's setae/bristles can punch into your hand like an ice pick. What a guy. Well, from my first look I put it into the botfly tribe, those blood-sucking flesh-feeders that just about cause most people to upchuck when anyone describes its life history.

To make sure I was close, I sent Brent's photo on to my old pal, Colorado Springs insect expert Eric Eaton (of Bug Guide). Eric and I have been pals ever since I met him at OMSI when he was 12 years old - and even then he was nuts about insects and spiders. Eric sent back a note saying I was in the ballpark, with a copy of a note he sent to a botfly guy back East.

This the way it played out:

From Brent - "Hi Jim. Kara found this loudly buzzing around her picture window. It's almost as big as a bumblebee. Is it in the fly family or what the devil is it? Thanks, Brent."

To Eric - "Howdy Eric. Never seen this beauty around here before. Know it? The receptacle/device behind the thorax is also intriguing. Jim."

From Eric - "Hi, Jim. Wow, great shots! This is a rodent botfly of some sort, genus Cuterebra, family Oestridae. I am including my friend Jeff Boettner in this because he is the leading authority on this genus and he is trying to get better data on distribution, hosts, etc. Can you please specify exactly where the images were taken? I'm gathering (it's) somewhere in the Pacific Northwest, but the more specific the location the better. Jeff can probably tell you what species it is once he has the geographic information (and date would be nice, too). Eric."

From Jeff Boettner - "Great fun! There are 3 all black female bots for me to sort out on this, and a tricky 3 at that! So I will try and do that soon. It would help a lot to see where you found it, i.e. location, habitat and date found, as that helps narrow the choices as well. Jeff Boettner."

From Brent to Jeff - "The location is Sisters Oregon, in the subdivision Tollgate a few miles west of town. It was captured three days ago. It is very much still alive and has laid several eggs, which stick to the glass like glue. I have other photos if needed. I found this video to be very interesting after you told me it was in the botfly family. From what I gather, the flies that use humans as hosts only live in Central / South America...NOT here?

https://vimeo.com/116518067. Thanks all for you help. I have never seen one of these here before, and wonder why it was found inside Kara's house, unless her cats had something to do with it? Brent."

From Jeff - "Hi Brent, Jim, and Eric, I would love to get the specimen! This is one of three all-black females that is quite hard to ID by photos, but your head shots were a huge help. I believe this is a female Cuterebra approximata, a western bot known mostly from British Columbia, CA, OR, ID, NV, UT, Montana and a few other states. Hosts are primarily Peromyscus maniculatus, the deer mouse.

"This would be an outstanding bot for me. I am trying to do DNA sequences of all the bots. I am putting finishing touches on a new DNA lab in our lab as we speak and hope to have it up and running in about two weeks. So great timing. I don't have a specimen of this species, but I have a lot of the other Peromyscus bots so will be fun to compare DNA from the west and east.

"Thanks for the nice series of pics as well. Great to have that of the fresh specimen. I hope to work on a better key for these guys once we get the DNA sorted out ... and this one needs a better key! So a huge help to my work to see this one. Jeff."

My gut feeling is Kara's cat carried a mouse into the house with fly on the body of the mouse. Be that as it may, now you know what I know, except for the saddle-like device on the end of the fly's thorax. I still don't know how that functions, or what it means to the fly. Stay tuned...