Fungi Key – Pisolithus




The identification of collections in the genus Pisolithus poses a problem for field mycologists. Field guides currently in print still largely use northern hemisphere names for what are now known to be Australian native species (Cleland 1934, 1935, Aberdeen 1979).

The genus Pisolithusis relatively common in Queensland, at least in coastal heaths and dry sclerophyll habitats. They seem to prefer well drained sandy or stony soils and to fruit along tracks and in other places where soils have been disturbed, for example where there has been mining activity.

Until about 1960, all collections would have been given a European name: P. tinctorius, the dyeball. Rauschert (1959) clarified the taxonomy and for the next 40 years some collections were deposited as P. arhizus, the Horse Dung Fungus. This name is used in modern field guides (Fuhrer 2005, 2009, Tait 2007).

After the publication of the Fungi of South Australia by Bougher and Syme (1998), field mycologists began to realise that there were several native Australian species in the genus. Martin (2002) demonstrated through comparisons of Australian material alongside collections from elsewhere in the world, using molecular data, that there were at least five Australian native species.

There are also many records under the unpublished name of Pisolithus boorabiensis (Priest), including a majority of the Queensland collections held at Queensland Herbarium.

There is still some debate as to whether P. tinctorius occurs in the southern hemisphere as an introduction in exotic pine plantations, this has not been confirmed by molecular data.

The key that follows was first published in Fungimap News in 2013 (Leonard & McMullan Fisher). It does not include P. tinctorius, but does include the unpublished P. boorabiensis (Priest).

Key to Pisolithus
1. Stipe height > gleba diameter 2.
1. Stipe height < gleba diameter 3.
2. Stipe clearly defined: mostly solid, golden brown (has rhizoids below).  Spores punctate Pisolithus microcarpus
2. Stipe mostly made up intertwined to merged bright orange rhizoids.  Spores reticulate Pisolithus croceorhizus
3. Peridium brown to black with or without gold mottling.  Spores 7-12 µm Pisolithus marmoratus
3. Peridium white or cream 4.
4. Peridium remaining white to pale cream, large.  Spores echinulate (spiny) 9-10 µm Pisolithus albus
4. Peridium parchment coloured when young, becoming dark buff, small to medium.  Spores verrucose (warty) 6-9 µm Pisolithus boorabiensis