Hi Andy

The 'notch/indent' is in fact where the blue colour (pruinescence) has been
rubbed off during mating. The marks become more extensive and darker the
more the dragonfly mates. In this position these marks are diagnostic for
Scarce Chasers.

Black-tailed Skimmer is probably found in the Adur valley. It is normally
found where there are bare/muddy edges to the water. It has a habit of
landing on the ground at the waters edge. This may be a useful pointer
towards ID as Ive not seen Chasers doing this. Better still, is the fact
that Chasers have dark bases to the wings and Skimmers do not.

As an aside to this 90 Scarce Chasers were recorded on a transect at the
Ouse Washes RSPB Reserve recently.

Also does anybody know if Scarce Chasers are on the River Arun?

Justin Atkinson

-----Original Message-----
From: Andy Horton [Mailto:Glaucus@hotmail.com]
Sent: 03 July 2002 12:59
To: INTERNET:dragonflies-uk@yahoogroups.com; UK Wildlife
Subject: [dragonflies-uk] Unidentified Dragonfly (Scarce Chaser)
 

Message text written by INTERNET:dragonflies-uk@yahoogroups.com
>I seemed to have got into a muddle over the identification of the two
dragonflies:

Scarce Chaser Dragonfly, Libellula fulva
Broad bodied Chaser, Libellula depressa

If it is the Scarce Chaser it may actually be the commoner of the two
species in the Adur area. I would like to see a photograph of a female to
be sure. I hope not because this could mean every time I identified a
Broad-bodied Chaser it could have been a Scarce Chaser.

The photograph by Allen Pollard is at:
http://www.ukthenandnow.co.uk/nature//bugs3.asp<

Hello,

I am now happy that the Broad bodied Chaser, Libellula depressa, is the
dragonfly at this time of year in the lower Adur Valley (where I live) and
that it is the Scarce Chaser Dragonfly, Libellula fulva, in the upper Adur
valley.

It is only the first species that I have seen regularly in flight. The
second one from the photographs only. The blue in the male Broad-bodied
Chasers from the lower Adur is very much paler than all of the photographs
I have seen. Exactly the same blue as the photograph above. However, the
female is really unmistakeable, even for a novice like me. the pairs of
orange spots are very clear.

Is the notch/indent in the abdomen important in the Scarce Chaser?  This,
however, does not seem to be clear or even present in most photographs of
the Scarce Chaser.

I do NOT know if the Black-tailed Skimmer, Orthetrum cancellatum, is
present from the Adur valley.This would make it very confusing. It does not
help that the common names are used for different species and do not always
match the ones in the books (not that vague reports are all that much use,
but scientific names always help).

There is at least one record of Emperor Dragonflies eating other
dragonflies.

There are missing records on my list for the Adur so if anybody has seen
species in this geographical region, I would be interested to hear about
them.

dragonfly.htm

Cheers

Andy Horton
Glaucus@hotmail.com
Adur Valley Nature Notes
Adur2002.htm
Adur2001.htm
Adur-6.htm  (Adur Nature Notes 2000)
Adur-5.htm  (Adur Nature Notes 1999)

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The photograph is very clearly a male scarce chaser.  It has too much black
at the tip of the adomen for broad-bodied chaser and not enough for
black-tailed skimmer.  Segments 9 and 10 are black (the two nearest the tip)
but only the inner area of segment 8 is black, this exactly matches the
pattern on scarce.  Black-tailed has segments 8 , 9 and 10 completely black.
Despite Jack's comments it does seem to have dark marks at the base of the
wings they are just not very clear due to the angle that the wings are held
at.   The eyes are grey/blue ruling out broad-bodied.  The lack of greenish
stripes and the thinner body also rule out broad-bodied.  Both black-tailed
skimmer and broad-bodied chaser have obvious yellow markings on the side of
the abdomen scarce and this photograph do not.

From: "Steve Babbs" <steve.babbs@ntlworld.com>