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Xylophagidae, dorsal - Coenomyia ferruginea - male

Xylophagidae, dorsal - Coenomyia ferruginea - Male
Plymouth Rock, Winneshiek County, Iowa, USA
June 11, 2014
Size: 16 mm with wings
At first I thought I had collected 2 different species but after checking BG, they are the same species. This is the other individual:
Is this sexual dimorphism?
swept in a weedy ravine (where a small bulldozer did work to fix erosion from a February rain on frozen ground)

Images of this individual: tag all
Xylophagidae, dorsal - Coenomyia ferruginea - male Xylophagidae, lateral - Coenomyia ferruginea - male Xylophagidae, eyes - Coenomyia ferruginea - male Xylophagidae, ventral - Coenomyia ferruginea - male

You got it right, so you can tell everyone which gender they filmed, tee hee! FYI - So far I have never filmed them, but here are 5 ways to tell the difference in the gender. (mostly visible in your images)

1) Overall Body coloring:
Dark brown with some lighter (lateral) abdominal bands = ♂
Shiny orange with light-orange abdomen, almost white = ♀

2) Leg colors:
Hind legs darker = ♂
All legs light = ♀

3) Abdomen size:
Not gargantuan, shorter than wings = ♂
Long, extending beyond the wings = ♀

4) Abdominal tip:
Stumpy, no obvious ticklers sticking out = ♂
Two ticklers that she usually cannot hide = ♀

5) Eye-gap:
Eyes meet on top of head, with almost no eye-gap = ♂
Head with a small eye-gap visible above antennae = ♀

Thank you very much Bob,
What a delight.
Are you going to post this on the info page so it's easily found by all?

I agree that it should be on there.
However, I will leave that to the experts, for now. Someday, I might become an administrator.

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