Home • Guyanagaster necrorhizus MCA 3950 v1.0
Guyanagaster necrorhizus; scale bar = 1 cm.  
Image credit: Rachel A. Koch
Guyanagaster necrorhizus; scale bar = 1 cm. Image credit: Rachel A. Koch

Guyanagaster necrorhizus MCA 3950 is a gasteroid fungus with close phylogenetic affinities to pileate-stipitate species in the genus Armillaria (Physalacriaceae, Agaricales, Basidiomycota). It is thus far only known to be associated with decaying leguminous trees in the Pakaraima Mountains of Guyana. Guyanagaster necrorhizus has a sub-hypogeous habit and is usually found attached to a decaying root. Morphologically, Guyanagaster necrorhizus has a unique suite of characters compared to other sequestrate fungi in the Basidiomycota: it has a persistant black peridium with pyramidal warts, a highly reduced stipe, and a gelatinous matrix that houses the spores which varies in color from white to bright pink to red with age. Unlike other sequestrate fungi, it does not produce any discernable pheromones for animal dispersal and the gelatinous nature of its gleba precludes it from wind dispersal. Its pathogenic capabilities remain unknown but suspected based on field observations and its close relationship to Armillaria spp.

The genome of G. necrorhizus will be useful in several lines of inquiry regarding fungal evolution. The stark difference in morphology of G. necrorhizus and its closely related mushroom-forming relative can provide insight to the molecular bases underlying gasteromycetation. Additionally, the genome may shed light on the selection pressures that lead to gasteromycetation, for instance, as an adaptation to climate or a particular dispersal vector.

If you would like to use this genome in your research, you are kindly requested to please contact Dr. M. Catherine Aime and Dr. Igor Grigoriev for permission.

Henkel, T.W., M.E. Smith and M.C. Aime. 2010. Guyanagaster, a new wood-decaying sequestrate genus related to Armillaria (Physalacriaceae, Agaricales, Basidiomycota). American Journal of Botany 97 (9): 1474-1484.