dipteran mating display?

[Robin Leech]

Ken,
I am not an entomologist, but....
I think it might be a bibionid, a march fly.  Some of them have some
interesting posturing.
Color black, sometimes shiny black, often with a pubescence all over.
Robin

----- Original Message -----
From: "Ken Kinman" <kinman2 at YAHOO.COM>
To: <TAXACOM at LISTSERV.NHM.KU.EDU>
Sent: Sunday, August 22, 2004 8:26 PM
Subject: dipteran mating display?


> Dear All,
>       Especially to entomologists on the list.  I know next to nothing
about mating displays in flies, but a gnat (ca. 4 mm. long) crawling on my
door window caught my eye.  It seemed to be displaying in a way that is
reminiscent of male jumping spiders trying to attract a female.  However,
the appendages being raised by this gnat seem to be the third (posterior)
pair of legs thrust upwards and arching somewhat forward towards the head.
After putting the gnat in a vial, it continued doing this, so I thought
perhaps it might be a threat posture as well.
>
>       Anyway, I'm just wondering if this is some kind of posturing that
certain male gnats usually do, and if so, to what family of gnats might it
belong?
>            ----- Thanks,
>                           Ken
>