''Multiclavula petricola'' is a species of

saxicolous This glossary of mycology is a list of definitions of terms and concepts relevant to mycology, the study of fungi. Terms in common with other fields, if repeated here, generally focus on their mycology-specific meaning. Related terms can be found ...

(rock-dwelling)

basidiolichen Basidiolichens are lichenized members of the Division (taxonomy), division Basidiomycota within the subkingdom Dikarya of the Kingdom (biology), kingdom Fungus, Fungi. They form a diverse yet much smaller group of lichens than the far more commo ...

in the family

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

. Found in Japan, it was

formally described A species description is a formal scientific description of a newly encountered species, typically articulated through a scientific publication. Its purpose is to provide a clear description of a new species of organism and explain how it differ ...

as a new species in 2020 by Hiroshi Masumoto and Yousuke Degawa. The

type specimen In biology, a type is a particular wikt:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally associated. In other words, a type is an example that serves to ancho ...

was collected from Katashina (

Gunma Prefecture is a landlocked Prefectures of Japan, prefecture of Japan located in the Kantō region of Honshu. Gunma Prefecture has a population of 1,937,626 (1 October 2019) and has a geographic area of . Gunma Prefecture borders Niigata Prefecture and Fuk ...

) at an altitude of ; here, in a shady

coniferous forest Conifers () are a group of cone-bearing seed plants, a subset of gymnosperms. Scientifically, they make up the division Pinophyta (), also known as Coniferophyta () or Coniferae. The division contains a single extant class, Pinopsida. All e ...

, it was found growing on wet

volcanic rock Volcanic rocks (often shortened to volcanics in scientific contexts) are rocks formed from lava erupted from a volcano. Like all rock types, the concept of volcanic rock is artificial, and in nature volcanic rocks grade into hypabyssal and me ...

. The lichen makes tiny white fruitbodies and has a globular

thallus Thallus (: thalli), from Latinized Greek (), meaning "a green shoot" or "twig", is the vegetative tissue of some organisms in diverse groups such as algae, fungi, some liverworts, lichens, and the Myxogastria. A thallus usually names the entir ...

. It is only known from the type locality. The

photobiont A lichen ( , ) is a hybrid colony of algae or cyanobacteria living symbiotically among filaments of multiple fungus species, along with yeasts and bacteria embedded in the cortex or "skin", in a mutualistic relationship.

partner of the lichen is the

green algae The green algae (: green alga) are a group of chlorophyll-containing autotrophic eukaryotes consisting of the phylum Prasinodermophyta and its unnamed sister group that contains the Chlorophyta and Charophyta/ Streptophyta. The land plants ...

that lives on the rock surface. The

Latin Latin ( or ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken by the Latins (Italic tribe), Latins in Latium (now known as Lazio), the lower Tiber area aroun ...

species epithet Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In Taxonomy (biology), taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany) ...

''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