Species of the Month January 2022

Taxomyia taxi

 

Taxomyia taxi is a small fly which causes a gall to appear on Yew (Taxus baccata). The adult fly is difficult to identify, but fortunately the galls are distinctive. Similar to the  'Artichoke Gall' encountered on Oak, this gall comprises of 60 - 80 terminal leaves that become clustered to form a single gall whose outer leaves are dark green and the inner ones almost white. The galls eventually turn brown and can stay on the plant right through to the next year.

You can find more images and information about Taxomyia taxi galls on NatureSpot and Plant Parasites of Europe.

The first step to finding this gall is of course to identify a Yew tree. This species can often be found in old churchyards and is sometimes used for hedges. You can find identification information from the Woodland Trust and view the Welsh distribution of Yew on Aderyn.

We only hold 21 records for Taxomyia taxi at SEWBReC (view the Welsh distribution map on Aderyn). However, it is likely to be under recorded and we are very interested to receive additional records to more accurately show its distribution.

If you spot Taxomyia taxi (or Yew) during January (or at any other time of year), please send us the record, ideally via SEWBReCORD or the LERC Wales App. Instructions on how to submit records are available here.