Candelariella is a genus of bright yellow, ocher, or greenish yellow crustose or squamulose lichens in the family Candelariaceae. Members of the genus are commonly called eggyolk lichens, goldspeck lichens, or yolk lichens.
Taxonomy
The genus was circumscribed in 1894 by Swiss lichenologist Johannes Müller Argoviensis, with Candelariella vitellina assigned as the type species.
In recent years, taxonomic research (aided by molecular data) has led to a surge in newly described Candelariella species. Since the 2000s, over a dozen species have been added to the genus, reflecting renewed interest and improved methods in lichen systematics. For instance, C. blastidiata (2017) and C. flavosorediata (2021) were discovered in Asia and Africa, respectively, followed by C. ruzgarii from Antarctica (2023) and C. ahtii from Asia (2024). This flurry of recent additions brings the total number of Candelariella species to around 40 as of 2025.
The 2025 analysis also resolved some nomenclature issues. It merged Candelariella makarevichiae (described 2018 from Korea) and C. subsquamulosa (2019, S. Korea) into synonymy with C. xanthostigmoides, since genetic data showed they belong to the same species. Several other sorediate species remain poorly known – for example, C. sorediosa (from the Himalayas), C. flavosorediata (Réunion), and C. magellanica (southern South America) – and lack molecular data. Ongoing research is needed to determine how these relate to the core Candelariella lineage.
