The first known
lichen-forming species in Chaetothyriaceae,
Ceramothyrium ryukyuense, was described in 2024 from
Okinawa Island in southern Japan. It was found growing on a living
palm leaf in a
subtropical coastal forest. The species is characterized by minute, brown ascomata and small, predominantly one-septate . It differs from non-lichenized
Ceramothyrium species, such as
C. paiveae and
C. philodendri, in its smaller asci and simpler spore structure.
Phylogenetic analyses based on nuclear
ribosomal DNA sequences placed
C. ryukyuense as a
sister species to
C. exiguum. The species is associated with a from the
Trentepohliales, marking the first confirmed case of lichenization within the family. ==Genera==