The subtleties of fly ID's - stereo pair added

[NikonUser]

A couple of warm days brought out a few overwintering flies including this small (6 mm) specimen.
A member of the House fly family (Muscidae), genus Caricea.

Final key characters for this genus:
1: 2 pairs of reclinate orbital bristles, the anterior pair situated at
about the middle of the frons and well before level of anterior ocellus.
2:frons with 2 pairs of inclinate frontal bristles.


Head shot: Nikon 4x Plan Achro objective (at 7.1x), 81 frames @ 0.01 mm, ZS PMax

[Barry]

Very nice images - with which objective was the top one shot; Micro-nikkor 105/4?

Best wishes,
Barry

[Eric F]

Absolutely fantastic fly photos NU!

Eric

[NikonUser]

Thanks, Barry and Eric.

Full lateral is with a Micro Nikon 105MF 2.8 @ f/8 on lens; 33 frames @ 0.1 mm. ZS PMax.

Both with styrofoam cup diffuser/single flash.

[Charles Krebs]

NU,

These look great! Wonderful details!

[NikonUser]

Thanks Charles. Good to see some bug life after 4 months of Winter.
Counting bristles is a bit easier than dissecting genitalia but the latter may be needed to get to the species level.

[LordV]

Wonderful stacks !
Have to admit i gave up on definitive ID's for flies when told I would have to dissect out the testicles to be certain
Brian V.

[RogelioMoreno]

Beautiful images, excellent details.

Rogelio

[NikonUser]

Thanks Brian & Rogelio.

Brian: 'Dissecting genitalia' is a bit of a misnomer. The interesting bits in males are really external but they tend to tuck them into the abdomen (modesty?).

I find the variation in the detail, between species, fascinating. Why would otherwise identical looking species, particularly in males, show such differences in external genitalia?

They also make great macro subjects.

left image: Nikon 20x microscope objective on bellows, 38 frames @ 0.005 mm; ZS PMax
right image: Nikon 10x microscope objective on bellows, 28 frames@0.01 mm; ZS PMax.

NU10-007

[booter]

Chaetotaxy made fun! Great images NU.

Scott

[rjlittlefield]

I haven't spent much time staring at fly genitals, but this one seems similar to some butterflies.

The structures are quite complex.

Any chance of getting that right side structure in stereo?

--Rik

[NikonUser]

Unlike moth genitalia which can be flattened into practically 2-dimensions, some fly genitalia are more like spheres with all sorts of bits and pieces. They probably are best seen as stereo pairs. however, I have never been able to see anything but 2 separate images when looking at stereo pairs.

[rjlittlefield]

Thanks to NU's generosity and the miracle of email, here are a couple of synthetic 3D views of this genitalia.

Rocking animations:



Stereo pair (crossed eye):



NU tells me this was a wet mount, in glycerine with no cover glass. Hairs sticking out of the surface layer of glycerine show up as very bright highlights. Those disrupt the off-axis views that we need for stereo. The rotating versions are straight out of PMax (except for levels adjustment and animation in ImageReady), but I had to do some manual cleanup in Photoshop to get the stereo pair that you see here.

This is a good test set -- interesting enough to get me excited, but troublesome enough to prompt some future mods to the software.

If I can get something that NU can see in stereo, now that'll be cool!

--Rik

[LordV]

Unlike moth genitalia which can be flattened into practically 2-dimensions, some fly genitalia are more like spheres with all sorts of bits and pieces. They probably are best seen as stereo pairs. however, I have never been able to see anything but 2 separate images when looking at stereo pairs.

NU re- 3-d cross-eye stereograms -have you tried sitting about 2 feet away from the screen and then holding a pencil or finger about 4" in front of your nose and focusing on that. If you can do that you should see a new image in the middle of the stereo pair. It's then a matter of trying to slide the finger/pencil out of the way whilst keeping the third image in view. With a bit of brain training you learn to lock this third image.
Brian V.

[NikonUser]

Brian:
Making slow progress. The pencil trick gives me 3 out of focus images images (4 counting the pencil), and a temporary head ache. As I slide the pencil away the 3rd middle bug image disappears with it.
Could be my brain is too old to train.