Flag Footed Fly

BugEZ · Post by **BugEZ** » Sat Jan 06, 2018 5:37 pm

Some long legged fly species (dolichopodidae) have ornamentation on their feet. The males use these markers somehow in courtship to display to the females that they have the right stuff. A typical male may look like this (image from BugGuide)

https://bugguide.net/node/view/659439

I found this specimen in my "winter reserve" in the freezer. I had to give it a bath to rehydrate the eyes, but but eye rehydration was only partially successful.
The feet proved to be more interesting. What high contrast between white and black patches!

The whole body shot using my rig with LED bucket light, 29mm UKA lens on extension, ~ 200 images, Pentax K-01 mirrorless camera.

The foot shots with my 10X OLY, 300mm Pentax 55-300mm zoom as tube lens, Pentax K-01 mirrorless camera, bucket LED lighting. about 30 images each for the two foot poses.

Processed with Zerene Pmax. Zerene generated the stereos, but I passed them through Stereo Photo Maker then down sized with Photoshop to lower file size.

All images

Keith

rjlittlefield · Post by **rjlittlefield** » Sat Jan 06, 2018 8:20 pm

Lovely!

You know I'm a sucker for stereo in general, but this one of those cases where it helps a lot for understanding.

Without stereo, I have a lot of trouble deciphering the structure in the first image, because of the way the critter's left foot lines up with the middle of his right leg. But with stereo, it's pretty simple.

Then in the other two, the stereo makes clear how the spines and bristles relate to the rest of the foot.

I don't think that I've ever seen one of these flies in person, so I also appreciate the up-close introduction.

--Rik

BugEZ · Post by **BugEZ** » Sat Jan 06, 2018 9:27 pm

Thanks Rik!

Yes the stereo helps solve the tangled leg mystery of what is where.

These Dolichopus genus flies I find beside a stream near my home in July. I think they only do one generation per year as I don’t see them in other summer months. On similar long legged Tachytrechus flies that I find beside a lake 1/4 mile away, the males have black spots on the tips of the wings. The Condylostylus doli that I find in my yard all summer long don’t have such obvious flags (to us). As several different related Condylostylus species co exist on my hosta leaves at the same time, they must have a different mating authentication scheme. Doli flies have solved the species verification check many ways.

Keith.

BugEZ · Post by **BugEZ** » Thu Jan 11, 2018 8:04 am

some photos of the foot with green background .

Keith

RobertOToole · Post by **RobertOToole** » Fri Jan 19, 2018 9:51 am

Thanks for the details of the feet Keith, that is interesting!

Robert

BugEZ · Post by **BugEZ** » Fri Jan 19, 2018 12:41 pm

Robert,

You are welcome!

Dolichopodidae are a passion of mine. Today I am headed out to gather some grass stems and look for one of the genus that spends their larval state mining grass stems. They overwinter inside the stem at ground level. Most doli are carnivores, but a few are not. These herbavoirs are very spicific about the right sort of plant (in this region normally tall native grass), but are little known, so it is a like gold panning hunting for them. You never know what you will find. So far all I have found is cold fingers and toes!

K

razashaikh · Post by **razashaikh** » Sat Jan 20, 2018 1:44 am

Photos came out very nice. Thanks for the information

RobertOToole · Post by **RobertOToole** » Wed Jan 24, 2018 2:57 pm

BugEZ wrote:Robert,

You are welcome!

Dolichopodidae are a passion of mine.

K

Always enjoy chasing the blue metallic Doli-flies in when I am in Florida. They are always fun to photography handheld.

I find fly biology interesting. During a case of insomnia I decided to read up on Tabanus for an upcoming photo tour I lead each year in South Africa and I was amazed! Some Sp. enter through the mouth of elephants and exit the base of the tusk when they mature!

What are the bee parasites? Wow. What an interesting and bizarre group that is!

Robert

BugEZ · Post by **BugEZ** » Wed Jan 24, 2018 6:46 pm

RobertOToole wrote:

Always enjoy chasing the blue metallic Doli-flies in when I am in Florida.

A friend sent me some Condylostylus mundus from Orlando Florida in a vial of alcohol so I could photograph the eyes. They are the bluest doli that I have photographed. They are a spectacular fly. I hope to visit Florida soon and see some.

Male

C. mundus by Keith Short, on Flickr

C. mundus showing spectacles by Keith Short, on Flickr

Female

Female Condylostylus species by Keith Short, on Flickr

Male C ? by Keith Short, on Flickr

RobertOToole · Post by **RobertOToole** » Wed Jan 24, 2018 8:10 pm

That looks like the one I photographed.

They seem to pretty easy to find sunny on sunny perch.

Robert