''Multiclavula petricola'' is a species of saxicolous (rock-dwelling) basidiolichen in the family

Hygrophoraceae The Hygrophoraceae are a family of fungi in the order Agaricales. Originally conceived as containing white-spored, thick-gilled agarics (gilled mushrooms), including ''Hygrophorus'' and ''Hygrocybe'' species (the waxcaps or waxy caps), DNA evide ...

. Found in Japan, it was formally described as a new species in 2020 by Hiroshi Masumoto and Yousuke Degawa. The type specimen was collected from Katashina ( Gunma Prefecture) at an altitude of ; here, in a shady coniferous forest, it was found growing on wet volcanic rock. The lichen makes tiny white fruitbodies and has a globular thallus. It is only known from the type locality. The photobiont partner of the lichen is the

green algae The green algae (singular: green alga) are a group consisting of the Prasinodermophyta and its unnamed sister which contains the Chlorophyta and Charophyta/Streptophyta. The land plants (Embryophytes) have emerged deep in the Charophyte alga as ...

that lives on the rock surface. The Latin species epithet ''petricola'' means "dweller on rocks". The Japanese name ''Iwa-no-shira-tsuno'' combines the Japanese words ''iwa-no'' ("on rocks") with ''shira'' ("white") and ''tsuno'' ("horns").

References

Hygrophoraceae Lichen species Basidiolichens Lichens described in 2020 Lichens of Japan {{Agaricomycetes-stub