Territorial behavior of Heleomyzid fly - Suillia

Wing Bristles

Those big bristles are common to all flies. Strictly speaking, hairs are extensions of a single cell. Bristles are complete organs, usually mechanosensory. There's a sort of ball-and-socket joint at the base of the bristle, and a neuron projects across the joint, sensing relative movement between the two parts.

Some of the bristles on the leading edge of the wing are hollow to the tip and have chemosensory neurons as well as mechanosensory. In this photo, the bristles that are sticking up are probably chemosensory, while the mechanosensory bristles are flatter against the leading wing vein.

Here's a drawing to show what these look like on Drosophila melanogaster.

… Stephen Hart, 22 October, 2008 - 1:27pm

thanks for correction

Thanks for correction on that. I was trying to emphasize that, as far as I can tell, prominent bristles on the leading edge of the wing are obvious in that genus. If you look at the diagram here:

That shows the bristles (spines?) as being prominent in Suillia, but maybe I was over-interpreting.
British Insects: the Families of Diptera--Heleomyzidae does mention spines along the costa as being a characteristic of this family. I guess that is where I was getting the idea, but thanks for calling me on thinking that was a character of the genus in particular.

… Cotinis, 22 October, 2008 - 2:54pm

No over-interpretation implied

I didn't mean to correct you, just to add some information. I haven't made any assessment of bristles on flies in general. That's a cool old figure, btw.

… Stephen Hart, 22 October, 2008 - 5:06pm

neat

I didn't know Suillia did that. acalyptrate flies have many weird and interesting behaviors but finding them is difficult. Many flies do have short appressed setae along the edge of the wing. Those long widely spaced setae (~spines) along the costal margin are useful for diagnosing some heleomyzids.

… Keith Bayless, 22 October, 2008 - 4:56pm