Species of the Month Jan/Feb 2020


Trioza centranthi


Trioza centranthi is a species of True Bug (Homoptera) which are difficult to identify as adults. Fortunately the nymphs form distinctive galls on the leaves of Red Valerian (Centranthus ruber), making it relatively easy to find and record this small species. The galls create red curled edges to the leaves as shown in the photo above.

Trioza centranthi is a historically rare and scattered species that has been increasing in recent years, primarily on the south coast of England. It was first recorded in Wales in 2018, and has since been found in a few spots along the coast and also as far inland as Llandrindod Wells. It would be very interesting to discover if the species is more widespread in Wales than the current distribution map (shown on Aderyn here) would indicate. We have just 18 records for the species at SEWBReC (not all have made it to Aderyn yet). More information and photos are available from British Bugs.

You may want to use the Aderyn distribution map of Red Valerian as a guide when looking for galls - please also record this host plant if your hunt is successful. You can find photos and information for Red Valerian on Naturespot.

If you spot Trioza centranthi galls during January, February (or at any other time of year), please send us the record, ideally via our Species of the Month form on SEWBReCORD (nb. you will need to be signed into SEWBReCORD to use this link). Instructions on how to submit records are available here.