Fungalpedia – Note 2659, Raesaenenia
Raesaenenia D. Hawksw., Boluda & H. Lindgr.
Citation when using this data: Meng QF et al. – Fungalpedia.
Index Fungorum, Faceoffungi, MycoBank, GenBank, Fig 1.
Classification: Parmeliaceae, Lecanorales, Lecanoromycetidae, Lecanoromycetes, Pezizomycotina, Ascomycota, Fungi.
Raesaenenia was intrudoced by Divakar et al. (2015) based on phylogenetic analysis using six-locus data set (ITS, LSU, mtSSU, RPB1, Mcm7 and Tsr1) to accommodate the type species Phacopsis huuskonenii Räsänen, which parasitizes Alectoria implexa. In their phylogenetic tree, Phacopsis huuskonenii was found to be sister to Protousnea within the Anzioid clade of Parmeliaceae, but it was clearly distinct from the type species Phacopsis vulpina due to significant differences in ascospore morphology. Divakar et al. (2017) synonymized Raesaenenia with Protousnea, reclassifying Raesaenenia huuskonenii as Protousnea huuskonenii. However, this change was not accepted by some authors (Diederich et al. 2018a, Lücking 2019). Later, phylogenetic analysis by Etayo et al. (2023) indicated that Phacopsis usneae is more closely related to Raesaenenia huuskonenii than to Protousnea vulpina. Thus, a second species, Phacopsis usneae, was transferred to Raesaenenia usneae, and the genus name Raesaenenia was kept in Wijayawardene et al. (2020).
Raesaenenia is characterized by Phacopsis-like structures but distinguished by its subcylindrical ascospores with thickened caps of wall tissue at each end. The Phacopsis-like features include subimmersed, shiny brown to black apothecia; a colorless to blackish-brown excipulum and hypothecium; septate, unbranched paraphyses with dark-brown pigmented caps; broadly clavate, eight-spored, Lecanora-type asci; and colorless, nonseptate ascospores that can be ellipsoid, ovoid, fusiform, lemon-shaped, or falciform (Hawksworth 1978, Hafellner 1987b, Triebel et al. 1988, 1995).
Type species: Raesaenenia huuskonenii (Räsänen) D. Hawksw., C. Boluda & H. Lindgren.
= Phacopsis huuskonenii Räsänen.
Other accepted species: Species Fungorum – search Raesaenenia.
Figure 1 – Raesaenenia huuskonenii redrawn from Triebel et al. (1995). a Ascus apices. b Ascospore. Scale bars: a, b = 10 μm.
References
Hawksworth DL. 1978 – Notes on British lichenicolous fungi. II. Notes from the Royal Botanic Garden Edinburgh 36, 181–197.
Wijayawardene NN, Hyde K, Al-Ani L, Tedersoo L et al. 2020 – Outline of Fungi and fungus-like taxa. Mycosphere 11 (1), 1060–1456.
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 1 July 2026