More guest blog from Andre Jagger....and the lovely fungi.... Back again to Tai Wo Hau Road Playground (大窩口道遊樂場), where the people go to play and the fungi grow to kill! It is time to look at the motivation that led me to the find of a Violet Oysterling. I had only ever read about the boletes that were not boletes, that is, in the order Boletales there are families of fungi for which the fungus has no resemblance to the traditional bolete, they are effuse-resupinate (unrestrained lying down), they don't have a stipe. One such family is the Coniophoraceae of which the genus Gyrodontium is a member and this genus has fungi with no gills or pores. No gills (lamellae) and no pores, what? Yes, meet the little killer with teeth!
From the virginal white fluffy, almost marshmellow to cotton like, texture of the hyphal mass comes the gradient blend into a golden yellow and then to yellow-brown spines that are part of the fertile surface of the species Gyrodontium sacchari. Where there is no vertical surface for it to attach to, the fertile surface will occur pretty much anywhere. In this case rain damages the teeth so they become unusual shapes instead of longer and more cylindrical. In the case where G. sacchari can attach to a vertical surface a slight to significant bracket like cap is formed and the teeth or spines are protected from the rain and some wind. In this case the spines become longer, slightly thinner and can form a nice regular cylindrical shape but this is not always the case. In the pileate state this fungus is completely stunning in its beauty. In moist conditions you can witness the existence of rhizomorphic hyphal cords extending outwards from the edge of the hyphal mass - assiting the main fungal mycelium to find new surface to expand upon and more food, see subpicture X., in the following picture.
Gyrodontium sacchari likes to grow in the warm moist protective areas between the peeling bark of dead wood logs and branches and the wood itself and then extend outward to find protective overhead cover for the formation of the hymenium (fertile surface). In this case G. sacchari was found growing between the bark and hard wood of dead Acacia confusa logs.
The spore print is a yellow brown. One further important find is that not unlike the boletes, Gyrodontium sacchari will go blue when properly bruised under the right conditions. The action of what is most likely to be a polyphenyl oxidase (enzyme) on the yellow pigments (hydroxytetronic acids). More often the bluing is faint and the blue oxidation product(s) mix with the pale yellow pigments of some parts of the flesh to form a greenish effect that seems to persist for some time. See subpicture IX., from the previous picture. However, note that when the yellow pigment is exposed to air it does not change colour and can be trapped in tissue paper, see subpicture VIII..
It is also noted that a bluish colour is seen in a different reaction with the addition of Betadine to the transverse section of the pileus - immediately above the hymenial layer.
The scent is subtle floral or fruity and slightly powdery (like some feminine perfumes). By subtle, not like Schizophyllum commune, much weaker - an aldehyde or ester not unlike banana. The taste of the raw basidiocarp, was much like the scent initially and then like molten candle wax with a lingering fruity aftertaste (after rinse of the mouth). The texture was smooth and slightly chewy.
Gyrodontium sacchari is a tropical-subtropical species - it has been found as far south as New South Wales in Australia and in India. Gyrodontium sacchari is also a saprobic fungus.
Note : The Wikipedia entry (as of 28-11-2022) for Gyrodontium sacchari places the genus in family Boletaceae and this is not correct, further there is currently only one other species in this genus, G. arizonicum, all others are now synonyms of G. sacchari.)