[Odonata-l] Tattered wings

[Nick and Ailsa Donnelly]

Tattered wings are very interesting.  Needham once purposely snipped bits of
wing off a libellulid (I forget which one) to see how far he could snip it
and still have the insect fly.  He got nearly to the nodus, if I recall.  I
did the same thing once with Pachydiplax and got the same results.  Except
Needham added a twist - he put a fine line of glue along the hind edge of
the wing.  This utterly stopped them, and he posited that they could not
flex the wing between the plus and minus veins.  (He had pointed out that
odonate wings are not flat, which was an important discovery) This is an
interesting idea, but I do not think the experiment was well designed.
 
I have noticed that extremely territorial, large libellulids fight so much
that their wings become seriously reduced in size.  I have seen Libellula
comanche with little left behind the costa and radial spaces, and still
flying.
 
In Guatemala I once saw ahead of me on a forest path a  long neuropterid
flying in a very clumsy manner.  Upon netting it I found it was an
Archilestes grandis with little left of any wing beyond the nodus.  It was
still flying, but not gracefully!

  _____  

From: odonata-l-bounces at listhost.ups.edu
[mailto:odonata-l-bounces at listhost.ups.edu] On Behalf Of Bob Reimer
Sent: Sunday, April 08, 2007 12:30 PM
To: odonata-l at listhost.ups.edu
Subject: [Odonata-l] Tattered wings


I was out at one of my favourite oasis in Oman yesterday and noticed what
seemed to be an unusual number of dragonflies with very tattered wings.  I'm
assuming this indicates that they are old or they had some encounters with
other predators that were unsuccessful.  I'm attaching pictures of a male
and female Trithemis annulata which seemed to be the worst for wear.  The
female is missing the tip of each wing while the male seems to be missing
most of one hind wing.  Neither seemed overly affected in its ability to
fly.  The dragonflies were on a tree beside an aqueduct carrying water
between two oases.  If you want to check out the area on Google Earth, the
coordinates to fly to are 24.50279N 55.97897E
 
Are there any records for how little of a wing can remain before flight is
totally impaired?  Is there any strong correlation between tattered wings
and age?
 
Thanks!!
 
Bob Reimer
Al Ain
United Arab Emirates
http://www.flickr.com/photos/rwreimer
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