Background

Russula kermisina

The distribution and abundance of New Zealand species of Russula and Lactarius is poorly known and there a number of reasons why we need to make it easier to recognise, record and understand the group better
- Russula and Lactarius form a significant group of over 60 ectomycorrhizal species associated with our native beech and tea-tree species as well as a number of introduced trees. As ectomycorrhizal symbionts they play a key role in the health of forest ecosystems.
- They are often large and colourful and noticed by non-mycologists.
- Eight species are currently listed as ‘Nationally Critical’ under the current conservation threat classification. Many more are listed as ‘Data Defficient’ due to poor historical recording. (Hitchmough, R. (compiler) 2002: New Zealand Threat System lists. Threatened Species Occasional Publication 23. New Zealand Department of Conservation).
The most recent keys to the group by Ross McNabb: Russula (1973), Lactarius (1971) are out of date. In adddition the work on Russula was published posthumously from a partial manuscript and over the years the key has proven difficult to apply reliably.
Russula and Lactarius species occur throughout the world and are relatively easy to recognise at the generic level, but it is often difficult to identify collections to known species due to variation in key characters such as colour. A multi-access electronic key is therefore an effective tool for assisting identification.