Fungalpedia – Note 2691, Rhymbocarpus

 

Rhymbocarpus Zopf.

Citation when using this data: Meng QF et al. – Fungalpedia.  

Index Fungorum, Faceoffungi, MycoBank, GenBank

Classification: Cordieritidaceae, Helotiales, Leotiomycetes, Pezizomycotina, Ascomycota, Fungi.

Rhymbocarpus was first mentioned by Zopf (1896) with the description of R. punctiformis, later designated as the type species of the genus. This type species is characterized by very small, sunken black apothecia. The epithecium is olive-green, while the hypothecium is colorless. The asci are eight-spored, and the spores are colorless, single-celled, ellipsoid to oblong or bean-shaped, measuring 10.7–12.5 × 3.6–5.4 µm.

Phylogenetic analysis based on three loci by Suija et al. (2015b) placed Rhymbocarpus within the subfamily Encoelioideae of Helotiaceae (Helotiales). However, Pärtel et al. (2017), through a phylogenetic analysis using five gene loci, proposed that the genus belongs to Cordieritidaceae, a view subsequently accepted by Wijayawardene et al. (2018) and Hyde et al. (2024). 

Since the introduction of the first species in the 19th century, 15 species have been introduced or transferred from other genera. For example, Rhymbocarpus geographici was transferred from Nesolechia geographici J. Steiner by Vouaux (1913a), and later to Phacopsis geographici by Keissler (1930). This species is excluded from the accepted list as it was not recorded in Index Fungorum (2025) or MycoBank (2025). There are 15 species recognized within this genus, with only one species having sequence data available. 

Type species: Rhymbocarpus punctiformis Zopf.

Other accepted species: Species Fungorum – search Rhymbocarpus.

 

References

Hyde KD, Noorabadi M, Thiyagaraja V, He M et al. 2024 – The 2024 Outline of Fungi and fungus-like taxa. mycosphere 15, 5146–6239.

Keissler KV 1930 – Rabenhorst’s Kryptogamen-Flora, Pilze – Die Flechtenparasiten. 8, 1–712.

Pärtel K, Baral H-O, Tamm H, Põldmaa K. 2017 – Evidence for the polyphyly of Encoelia and Encoelioideae with reconsideration of respective families in Leotiomycetes. Fungal Diversity 82, 183–219.

Suija A, Ertz D, Lawrey JD, Diederich P. 2015b – Multiple origin of the lichenicolous life habit in Helotiales, based on nuclear ribosomal sequences. Fungal Diversity 70 (1), 55–72.

Vouaux L. 1913a – Synopsis des champignons, parasites des lichens. Bulletin de la Société Mycologique de France 29 (1), 399–446.

Wijayawardene NN, Hyde KD, Lumbsch HT, Liu JK et al. 2018 – Outline of Ascomycota: 2017. Fungal Diversity 88 (1), 167–263.

Zopf WF. 1896 – Übersicht der auf Flechten schmarotzenden Pilze. Hedwigia 35, 312–366.

 

Entry by

Meng QF, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai, 57100, Thailand and School of Public Health, Zunyi Medical University, Guizhou 563000, China.

 

Published online 8 July 2026

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