Posted by blowave on 30-01-2012 22:03
#13
Tony Irwin wrote:
Janet - subalpina has a dark anterior spiracle, and a less-infuscated lower calyptra - the pale spiracle and infuscated calyptra on your specimen would exclude this species. As for the convexity of the occiput, I can't really see any difference between your specimen and those vicina in the gallery (allowing for different angles of view). The size of the specimen is well within the range of vicina - all carrion-feeding species are able to produce small individuals if conditions require it. If you want to make this into anything other than vicina, you will have to collect the specimen!
Are you certain that
subalpina always has a dark anterior spiracle Tony? I know that
uralensis can have a pale one which is mentioned in the keys by Rognes, there's no mention of colour for
subalpina but that may have been covered earlier in the keys.
The keys also state the lower calypter can occasionally be slightly infuscated.
Collecting a specimen is all very well, if I could ascertain the fly was suspect, and if I could catch it before it buzzed off, and if I was willing. I sometimes see Calliphora photos on the forum which can be identified so I'm trying. :D
Unfortunaltely I can't find any photos of mine of a female
vicina showing the occiput from that angle. I might be looking at it wrong, but there looks to be a ridge which I have marked with arrows, it doesn't look to be concave rather more convex.