T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Cyttaria gunnii (Beech strawberry)

Kingdom: Fungi
Division: Ascomycota
Class: Leotiomycetes
Order: Cyttariales
Family: Cyttariaceae
Genus: Cyttaria
Species: C. gunnii
Binomial name: Cyttaria gunnii
Synonym: Cyttaria purdiei
Common names: Beech strawberry, Myrtle orange, Puku tawai

Cyttaria gunnii commonly is an orange-white coloured ascomycete fungus present in New Zealand and Australia. This fungus is present throughout New Zealand and is found only on Lophozonia menziesi (Silver beech trees).

Germinatinating spores invade the tissues of new shoots and produce chemical substances which cause the proliferation of the host tissue and lead to the production of localised galls. The globose, woody, galls are perennial and produce clusters of fruiting bodies late spring and summer (November to January). As the fruiting bodies grow they cover and obscure the small gall on which they are borne.
The immature fruiting bodies are lighter in colour than the mature honeycombed fruiting bodies which are a fawn to bright yellow colour. They are up to 2.5 cm in diameter and are covered by a membrane that bursts, uncovering a network of concavities. The spore print is black and the spores measure 12 by 7–12 μm and are discharged as visible clouds. 

Diagnostic features of Cyttaria gunnii are:
1 The galls on branches are rarely more than twice the diameter of the host branch, and usually occupying about two-thirds of its circumference.
2 The galls on the stems usually form encircling bands.
3 The bark under the gall is contorted and has sharp spines.

Beech strawberry galls with a section of the outside membrane removed showing the internal honeycomb construction.

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