A new genus,Zhurbenkoa, and a novel nutritional mode revealed in the family Malmideaceae (Lecanoromycetes, Ascomycota)

Abstract

Lichen-inhabiting fungi are highly specialized mycoparasites, commensals or rarely saprotrophs, that are common components of almost every ecosystem, where they develop obligate associations with lichens. Their relevance, however, contrasts with the relatively small number of these fungi described so far. Recent estimates and ongoing studies indicate that a significant fraction of their diversity remains undiscovered and may be expected in tropical regions, in particular in hyperdiverse fog-exposed montane forests. Here, we introduce the new genus Zhurbenkoa, from South America and Europe, for three lichenicolous fungi growing on thalli of the widespread lichen genus Cladonia (Lecanorales). Phylogenetic analyses based on combined sequence data of mt and nuc rDNA obtained from Andean populations (Bolivia) placed Zhurbenkoa as a member of Malmideaceae, a recently introduced family of lichen-forming fungi in the class Lecanoromycetes. Zhurbenkoa is closely related to the genera Savoronala and Sprucidea. The new genus is characterized by the development of grayish brown to almost black apothecia lacking an evident margin, an epihymenium interspersed with crystals (often seen as pruina), a strongly conglutinated hymenium made of noncapitate and sparsely branched paraphyses, a colorless exciple composed of radially arranged hyphae, a Lecanora/Micarea-like ascus type, and aseptate or 1-septate ellipsoidal colorless ascospores. Zhurbenkoa includes two Neotropical (Z. cladoniarum, Z. latispora) and one widespread (Z. epicladonia) species. The lichenicolous trophic mode is documented for the first time in the Malmideaceae, which until now included only lichen-forming associations between fungi and green algae.

Microbiome in Cladonia squamosa Is Vertically Stratified According to Microclimatic Conditions

“…EukCL4 belonging to the class Arthoniomycetes was mostly found at the apical and middle parts of thalli and closely related with E. trypethelii. E. trypethelii is known as a lichenicolous fungus that grows on several corticolous lichens with crustose thalli, such as Graphidaceae, Pertusaria, and Lecanora, in subtropical and tropical regions without causing them any visible damage (Flakus and Kukwa, 2012;Ertz et al, 2014). The species was not observed in the previous study on LAF from several lichens on King George Island, Antarctica (Park et al, 2015).…”

Australidea (Malmideaceae, Lecanorales), a new genus of lecideoid lichens, with notes on the genus Malcolmiella

“…BLAST searches and preliminary analyses suggested that Australidea canorufescens is a member of the Malmideaceae. To further assess the phylogenetic position of this species within the family, sequences from representatives of all genera known to belong to Malmideaceae were downloaded from GenBank: Cheiromycina (Muggia et al 2017) (Flakus et al 2019). For all these genera, mitochondrial SSU was available in GenBank; we also included LSU when that was available (see Table 1).…”

Three overlooked species of Bacidia from insular Laurimacaronesia

“…Based on the well developed and strongly gelatinized proper exciple with radiating hyphae, lack of constrictions at the ascospore septa and the abundance of crystals in the hymenium, we suggest that B. deludens is a member of the Malmideaceae. Among the genera currently classified in the Malmideaceae (Spribille et al 2020, Wijayawardene et al 2020), Malmidea , Sprucidea and Zhurbenkoa possess mainly non‐septate ascospores and a brown hypothecium, Malmidea also having halonate ascospores, Sprucidea producing sporodochia and Zhurbenkoa having a parasitic life‐style on other lichens (Kalb et al 2011, Cáceres et al 2017, Flakus et al 2019). Puttea includes species with non‐septate ascospores, minute apothecia with a poorly developed proper exciple, and (when pigmented) brown pigment caps on the terminal cells of the excipular hyphae (Dillman et al 2012).…”

“…The circumscription and generic classification of the Malmideaceae is poorly known and it has been suggested that several additional taxa may belong in that family, e.g. the genus Porpidinia as well as couple of species formerly referred to Phyllopsora in the Ramalinaceae or the large and distantly related Lecidea , the type of which belongs in the Lecideaceae (Breuss and Lücking 2015, Kistenich et al 2018, 2019, Palice et al 2018, Flakus et al 2019). At the moment, we see three options to classify our new species: 1) a new genus in the Malmideaceae could have been erected.…”