british leafminers      
  home | mines| species | plants| mine-keys | search | updates | newsletters | contributing | books
miner matters - september 2005
< newsletters
The Summer generation of Emmetia (Coptotriche) marginea

Rob Edmunds and John Langmaid found examples of Emmetia type mines on Bramble (Rubus fruticosus) at several sites in shady sitautions in both Hampshire and Surrey in the Summer (2005).

They differed from the typical autumn generation mines of E.marginea as they formed large, flat mines, which could extend from the mid region of the leaf to the edge. The Summer generation mines in sunny sites were the typical compact E.marginea type.

Some mines were at the edge of the leaf and caused it to curl over.

An example of one of the broad flat mines is illustrated opposite.

The mines were transparent when held up to the light and there was only limited evidence of a silken portion in the centre of the mine.

Some larvae were pale in colour and had a pale colouration to the head capsule. This is in contrast to the autumn generation of E.marginea, which is a darker green colour and has more pronounced capsule pigmentation (see comparison).

 

 

 

Images © Rob Edmunds

Mines from different localities were bred out by John and Rob and all proved to be Emmetia marginea. It would seem that E.marginea can form these large flat mines in shady situations in the summer, presumably due to it being easier for the larvae to mine the softer tissues in the freshly formed leaves.

Rob Edmunds & John Langmaid

 
Phyllonorycter issikii (Kumata, 1963)

 

This leaf miner was introduced into Eastern Europe in the 1970s from East Asia and is spreading to the West of Europe, being found as far as Germany in 2002. It is considered a pest species and is a miner of various Tilia (Lime) species preferring trees growing in forest stands and lower branches of trees in areas such as parks, avenues, churchyards etc. It has two generations a year.

It has also spread to the Baltic States and the photos below are from Vilnius, Lithuania. The mines are on Tilia cordata

Images © Paulius Ceponas

www.leafmines.co.uk