Battarrea phalloides - Sandy Stiltball

Taxonomy

Phylum: Basidiomycota

Class: Agaricomycetes

Order: Agaricales

Although cacti can survive in desert conditions by storing water within their succulent structures, Battarrea phalloides takes an exactly opposite approach: it looks like a dead, dried plant even when it is fresh and newly emerged from its underground 'egg'. In Britain this is a rare find, although it may be more common than records suggest: despite its large size (specimens 25cm tall are not unusual) its 'dry stick' appearance does little to attract attention.

The specimens shown here were photographed by Doug Collins, with whose kind permission they are shown here and in Pat O'Reilly's new book Fascinated by Fungi, published by First Nature in September 2011.

Identification guide

Cap	The conical to hemispherical cap is covered initially by the upper part of the universal veil, beneath which there is a spore sac attached to the stem. When the dried out upper part of the universal veil blows away, the rusty-brown upper surface of the spore-bearing layer is open to wind and rain, and in this way the spores are dispersed; the underside of the cap is buff. Cap diameter ranges from 1 to 4cm.
Stem	Typically 10 to 25cm tall (exceptionally to 40cm) with a diameter 4 to 15 mm; scaly or fibrilose; rufous brown; base volva-like.
Spore print	Rusty-brown, finely and densely warted, diameter of 5 to 6.5µm.
Odour/taste	Not distinctive.
Habitat	In dry sandy areas such as hedge banks or beneath deciduous trees, particularly on raised sandy banks..
Season	September to November.
Occurrence	Rare.
Similar species	This is the type species of the Battarrea genus and the only species in this genus known to occur in Britain. Other stiltballs, such as Tulostoma brumale, are much smaller and do not produce rusty-brown spore dust.