''Candelariella aurella'', the hidden goldspeck lichen or eggyolk lichen, is a yellow

crustose Crustose is a habit of some types of algae and lichens in which the organism grows tightly appressed to a substrate, forming a biological layer. ''Crustose'' adheres very closely to the substrates at all points. ''Crustose'' is found on rocks and ...

lichen A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship.Candelariaceae ''Candelariaceae'' is a family of lichen-forming fungi in the order Candelariales. It contains seven genera and about 73 species. The family was circumscribed by Finnish lichenologist Rainar Hakulinen in 1954 to contain the type genus In biolo ...

. It is commonly found on

calcareous rock Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime or being chalky. The term is used in a wide variety of scientific disciplines. In zoology ''Calcareous'' is used as an adje ...

or wood or bark exposed to sunlight and which may have calcareous dust in areas with lime soils. The

thallus Thallus (plural: 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. Many of these organisms wer ...

areolate Lichens are composite organisms made up of multiple species: a fungal partner, one or more photosynthetic partners, and sometimes a basidiomycete yeast. They are regularly grouped by their external appearance – a characteristic known as their ...

with scattered small (0.1–0.3 mm), rounded to elongated yellow areolas. It has a global distribution and occurs on

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

and calcareous

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

in the

Sonoran Desert The Sonoran Desert ( es, Desierto de Sonora) is a desert in North America and ecoregion that covers the northwestern Mexican states of Sonora, Baja California, and Baja California Sur, as well as part of the southwestern United States (in Arizona ...

Arizona Arizona ( ; nv, Hoozdo Hahoodzo ; ood, Alĭ ṣonak ) is a state in the Southwestern United States. It is the 6th largest and the 14th most populous of the 50 states. Its capital and largest city is Phoenix. Arizona is part of the Fou ...

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

, and

Baja California Baja California (; 'Lower California'), officially the Free and Sovereign State of Baja California ( es, Estado Libre y Soberano de Baja California), is a state in Mexico. It is the northernmost and westernmost of the 32 federal entities of Mex ...

. It occurs in Joshua Tree National Monument. ''

Phoma candelariellae ''Phoma candelariellae'' is a species of lichenicolous fungus, lichenicolous (lichen-eating) fungus in the family Didymellaceae. It is found in the Central Anatolia Region of Turkey and in Ukraine, where it grows parasitism, parasitically on the ...

'' is a species of lichenicolous (lichen-eating) fungus that has been documented parasitisising the apothecia of ''Candelariella aurella'' individuals in Europe. Infection by the fungus results in reduced

ascospore An ascus (; ) is the sexual spore-bearing cell produced in ascomycete fungi. Each ascus usually contains eight ascospores (or octad), produced by meiosis followed, in most species, by a mitotic cell division. However, asci in some genera or s ...

production, and eventual destruction of the

hymenium The hymenium is the tissue layer on the hymenophore of a fungal fruiting body where the cells develop into basidia or asci, which produce spores. In some species all of the cells of the hymenium develop into basidia or asci, while in others some ...

of the affected apothecia.

References

aurella Lichen species Lichens described in 1796 Lichens of Europe Lichens of North America Taxa named by Georg Franz Hoffmann {{Ascomycota-stub