Miner Matters

< back | home

 Phyllonorycter medicaginella - will it be a new British miner?

Several miners had an excellent year in Holland last year and it was Willem Ellis who alerted us to this fact. His promptings lead to new discoveries of miners such as Cosmopterix zieglerella (Lep) in several localities in the UK.

Phyllonorycter medicaginella (Lep: Gracillariidae) also had spread rapidly in Holland in 2003 and the miner is shown opposite.

It occurs on Black Medick (Medicago lupulina), but it is much more common on Melilot, particularly White Melilot (Melilotus alba).

The plant and the miner occur on waste ground, even well into urban areas. The plants may be heavily mined, with up to ten mines on  a branch or two out of three leaflets mined.

The mines are easily spotted because the leaflets are strongly folded, pod-like, and, when the mine has fully developed there is little green tissue left.

The cremaster of this pupa of this species is distinctive - having four elongated hooks.

 Images: Willem Ellis, Holland, 2003

Lepidopterous miners of Holm Oak - a puzzle.

At the end of April Rob Edmunds discovered mines on Holm Oak (Quercus ilex) which could appear quite serpentine and caused blackening to the upper leaf surface.

Initially, they looked dipterous, which was a surprise as there are only two dipterous miners on Oak -Japanagromyza viridula on Quercus rubra from Nova Scoria and Ontario, throughout the eastern United Sates to the Gulf of Mexico and Japanagromyza quercus on Quercus glauca in Japan! Both form blotch mines . Japanagromyza is most closely related to Japagromyza salicifolia, a leaf-miner of Populus and Salix in southern Europe and extending eastwards through Israel and Turkey to Kirghizia in the former USSR.

When the mines were dissected they were found to contain lots of round shiny frass pellets and cast skins from the larval ecdyses.

The mystery was finally solved by John Langmaid who had observed these mines develop into the more characteristic blotch mines of Phyllonorycter messaniella (Lep: Gracillariidae) on this pabulum.

Images: Rob Edmunds, 27.iv.2004, Fleet, Hants, VC12
British Plant Gall Society:                                                                                                                                The programme of field meetings for this society is now available and includes visits for leaf miners also:http://www.btinternet.com/~bpgs/Meetings.html#summary      
Newsletter of leafmines.co.uk 

May 2004