Posted by John Showers on 24-09-2015 16:53
#1
On 6.vi.2015 I noticed a number of gallery leaf mines on the upper surface of the lower leaves of a Helleborus lividus in my garden in Rothwell, Northamptonshire, UK. It appears to be dipteran in origin as the gallery contains lines of frass alternating on either side of the mine. The only European fly that is known to mine Helleborus is
Phytomyza hellebori but that species is reported to produce a black blotch mine on the underside of the leaf. Theses mines were on the upper side. I have photographed the mine and attempted to raise an adult of the causer. However the leaves shriveled and died and no adult was found. I have photographed the dead laves which show a puparium or larva under the leaf cuticle with two breathing tubes projecting. I have retained these samples. If anyone knows what this might be or wishes to examine the specimen, please let me know.
Posted by Tony Irwin on 24-09-2015 21:45
#3
I think this is one of those cases of
Phytomyza hellebori, where the larva has decided to pupate in the upper surface rather than lower (apparently happens occasionally). I did consider whether it might be one of the polyphagous agromyzids, but the frass pattern is wrong for
Chromatomyia species, and I believe
Liriomyza do not pupate in the mine.
As far as I can recall,
Helleborus lividus may be a new host record for Britain.
Edited by Tony Irwin on 24-09-2015 21:49
Posted by John Showers on 24-09-2015 22:21
#4
Thanks Tony. I think you are right about this being a new host. I have been unable to find any references to it.
Regards,
John