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17th March 2017

The invertebrate Group Workshop Brocks Hill, Oadby

Tom Higginbottom, 5 Spennithorne Road, Skellow, Doncaster, DN6 8PF


This was a fascinating day in which a number of suggestions were made and discussed for the future development of the BPGS.


Some Musings – Chris Leach

In a Power Point presentation Chris offered a number of ideas to be considered by the BPGS. He felt that many of the existing guides and keys to galls focused primarily on the gall structure, but now the BPGS should be aiming to generate information on the gall causers and the gall communities. Margaret Redfern has plans to write keys to the organisms discovered within gall structures to aid the identification of the larvae of gall causers and other possible inquilines and parasites. It was thought that Michael Chinery’s Britain’s Plant Galls, a photographic guide could provide a model for a guide to gall causers of specific organisms or groups, and that he would co-ordinate these efforts leading to another publication. Approaching the FSC to produce another fold-out chart could also be another step forward, while Peter Shirley expressed a willingness to investigate the production of posters illustrating these organisms. To make these new initiatives a success BPGS members and fellow naturalists will need to provide photographs of gall causers and gall communities, ideally with the insects and larvae identified.


While praising the efforts made by Alan Rix in maintaining and developing the BPGS website, Chris also put forward ideas for modifying the website to appeal to younger people. His thirteen year old grandson had provided guidance on how to use Windows Movie Maker. In a single evening Chris had produced a visually appealing video about gall causers using photographs from Robin Williams and Michael Chinery, which led to spontaneous applause from the group. There was a general consensus that the society needed to embrace more fully the electronic age, but there was also an acceptance that this would be challenging and needed the participation of members to make it possible. However, there were some points raised that it was not always possible to be specific about identification from photographs and that keys to gall causers would still be important. Chris planned to have further videos available for the AGM. Things have already begun to move forward because last year Peter Shirley established a plant gall Twitter account which has about ninety members.


Images of Galls using a Veho video microscope - Peter Cooke

In a stimulating presentation Peter demonstrated how he had a modified the basic microscope making it even more flexible, which allowed him to control the magnification and illumination. He showed a whole series of perfectly focused images revealing gall larvae found in a number of different hosts, including a new record for Warwickshire of Dasineura similis on heath speedwell. This record for Hay Wood appears to be only the second for the UK.

Some of Peter’s  images.

Hand books on different Groups - Jerry Bowdrey

The new Chairman of the BPGS presented a series of thoughtful well structured proposals, based on his museum expertise, for a series of handbooks about the gall causers, beginning with gall wasps. These handbooks would provide guidance on a number of themes including: the host plant and the gall structure, how to rear and identify the gall causer, the use of the microscope, and the mounting, preservation and labelling of specimens. It was hoped these publications would stimulate further research into life cycles, distribution, parasitoids and inquilines.  To support this it was envisaged that useful guides, books, papers, websites etc. would also be included in an appendix as well as a bibliography.


Galls from the North –Tom Higginbottom

Photographs were presented of some of the more unusual galls discovered during the Dumfries and Galloway weekend. Images were also shown from the less well-recorded Vice-County 65, North West Yorkshire and galls recorded in South Yorkshire for the first time.


Cynipids on Centaurea scabiosa greater knapweed - Jerry Bowdrey


Jerry shared his initial research discoveries of the Aylacini, the herb gall wasps on Centurea scabiosa. The gall causers listed in the FSC keys are: Phanacis centaureae, Isocolus fitchi, I. scabiosae which cause indistinct swellings in the stem while I. rogenoferi swells the base of a bract or an achene. It was felt that further research is needed on these uncommon, difficult to find gall causers, because they are so well hidden in the stem or flower heads. The few records seem to be from the south of the country. Jerry would be happy to receive C. scabiosa specimens from members to support his investigations.


Nematode galls – Brian Spooner

Brian presented pictures of a currently unidentified nematode which had caused discrete gall swellings on the leaves of amphibious bistort Persicaria amphibia, found recently in Surrey a new host for such galls. The nematode belongs in genus Subanguina, of which several other species are known in Britain, but has not yet been determined to species. It is currently under study by Rebecca Lawson (FERA), who suggests it could potentially be undescribed and will be carrying out DNA sequencing. He also mentioned another nematode, Subanguina guizotiae, recently reported by David Biggs from the Isle of Wight galling leaves of niger (Guizotia abyssinica), a bird-seed alien. This is an Ethiopian species new to Europe. Other undetermined nematode leaf galls have been found reported in British literature from Hieracium, Lapsana, Leontodon and Prunella species. Further collections of such galls are desirable to identify the causers and their host ranges, and would be welcomed for study by Rebecca Lawson. Her address is: Rebecca Lawson, The Food and Environment Research Agency, Sand Hutton, York, YO41 1LZ. email: bex.lawson@fera.gsi.gov.uk


Brian also showed images and specimens of galls due to the mite Aceria heteronyx on twigs and branches of Norway maple (Acer platanoides) from Surrey, as reported recently in Cecidology. This is the original host from which the mite was described and was not previously known in Britain. It has now been found at several localities in Surrey and may be more widespread.


Argentinian galls – Jerry Clough

Jerry shared beautiful photographs of the landscape of Argentina and a series of striking images of galls on a variety of hosts.


Gall causers – Ian Farmer

Ian, like Peter Cooke, has been investigating the larvae and adult gall causers of a variety of gall structures using a Veho microscope and shared his amazing images with the group.


 Some of Ian’s  images.




To conclude the day, Chris provided a light-hearted presentation, including home-made apparatus, about his continuing investigations into Semudobia galls.  He also led thanks to Maggie Frankum for yet again organising a superb day.


Phyllocoptes populeti on aspen

Coleosporium tussilaginis

-on Senecio vulgaris

 Pontania bridgemanii

larva-in gall

Dasineura similis gall

+ larvae on Veronica officionalis