Pradeep Kumar Divakar

Molecular studies have repeatedly demonstrated that morphology-based species circumscriptions often underestimate the diversity of lichenized fungi by masking distinct evolutionary lineages under a single species name. In Parmelina, a lichen-forming ascomycete genus whose extant diversity originated during the Miocene and Pliocene, several cryptic species have recently been recognized. Here, we evaluated the performance of the fungal DNA barcode marker, the internal transcribed spacer (ITS) region, in discriminating species that diverged at different evolutionary times. ITS reliably discriminated all the species that originated during the Miocene, for which intra- and inter-lineage distances form a clean, non-overlapping barcode gap (0.0137–0.0162 substitutions/site), but it failed to resolve the two species complexes that radiated during the Pliocene. Barcode-gap analyses based on genetic-distance thresholds previously established for parmelioid lichens produced congruent results, confirming species discrimination among Miocene lineages while highlighting inconsistencies in the current circumscription of two Pliocene species complexes. We also provide a curated ITS DNA barcode reference library comprising 749 accurately identified specimens sampled across the geographic range of Parmelina. Expanded taxon sampling further revealed new country records for P. clandestina in Greece, Hungary, India, Norway, Slovakia, and Switzerland, and for P. mediterranea in France, Greece, Morocco, Turkey, and Switzerland. Our results demonstrate that the discriminatory power of the fungal ITS barcode depends on the evolutionary age of species divergence, successfully identifying older lineages while revealing limitations for more recently diverged taxa. Automated, distance-based delimitation with ABGD and ASAP independently recovered every Miocene lineage, split P. atricha into two entities and assigned the whole P. tiliacea aggregate to a single partition, corroborating this conclusion.

Etayo, J., Divakar, P. K. & Hawksworth, D. L. 2026. Neue und interessante flechtenbewohnende Pilze aus Südafrika. – Herzogia 39: 134 –150. Als Ergebnis einer Sammelreise in die Kapprovinzen im Jahr 2005 wurden in Südafrika siebzehn Arten von flechtenbewohnenden Pilzen registriert. Vier davon erwiesen sich als neue Arten: Cercidospora capensis auf Caloplaca s. lat., Endococcus bicinctus auf Parmotrema, Feltgeniomyces combeae auf Combea mollusca und Trematosphaeropsis xanthomaculinae auf Xanthoparmelia hottentotta. Für einige der anderen Arten konnten die bekannten Verbreitungsgebiete erheblich erweitert werden. Die Anzahl der bekannten flechtenbewohnenden Mykobiota Südafrikas steigt damit auf 34 Taxa, von denen einige noch keinen spezifischen Namen haben.

The genus Canoparmelia Elix & Hale contains c. 40 species, predominantly occurring in tropical and subtropical regions. The genus is characterized by having relatively narrow, subirregular lobes with rotund or subrotund eciliate margins, a pored epicortex, the presence of isolichenan in the cell walls, bifusiform conidia, and simple rhizines (Elix 1993; Crespo et al. 2010 b ). Phylogenetically, it belongs to the Parmotrema clade of parmelioid lichens (Crespo et al. 2010b). Since its original circumscription (Elix et al. 1986), species have been transferred to other genera, including Austroparmelina A. Crespo et al . (Crespo et al. 2010 a ), Crespoa (D. Hawksw.) Lendemer & B. P. Hodk. and Parmotrema A. Massal. (Crespo et al. 2010 b ; Hawksworth 2011; Lendemer & Hodkinson 2012; Kirika et al. 2016). In addition, some species of the genus Crespoa are morphologically similar to certain Canoparmelia species, which leaves uncertainty regarding the identification of the samples.

Antarctic terrestrial photosynthetic biota is dominated by cryptogamic communities, which are largely restricted to scarce ice-free areas. Among these, nunataks constitute habitats of remarkable biogeographical interest, as they may harbor distinctive biotic assemblages worthy of investigation. This work presents a comprehensive assessment of lichen diversity on Antarctic nunataks. The lichen flora of four nunataks on the Hurd Peninsula (Livingston Island, maritime Antarctica) was investigated. Specimens were identified using an integrative approach combining morphological assessment and DNA barcoding. This survey revealed a high and potentially underestimated species richness, with 39 confidently identified and several additional taxa requiring further taxonomic resolution. A review of published records of lichen occurrence in nunatak and non-nunatak environments throughout Antarctica was used to evaluate patterns in taxonomic, biogeographical, and morphotype composition. This synthesis showed that nunataks support lower species richness than other ice-free environments. Most of their taxa occur in non-nunatak areas, consistent with patterns observed locally on the Hurd Peninsula. Floristic overlap seems greater in continental Antarctica, suggesting a stronger influence of nunatak-associated environmental constraints in the maritime region. These results underscore the ecological significance of nunataks as environmentally filtered habitats and highlight their relevance for understanding biodiversity patterns and community assembly in Antarctica’s terrestrial ecosystems.

High‐quality reference genome assemblies have become essential for deepening our understanding of biodiversity, yet obtaining them for many species remains surprisingly challenging. Drawing on experiences from the European Reference Genome Atlas (ERGA) community, we focus on permit and sample‐handling procedures leading up to nucleic acid sequencing, covering tasks such as ensuring ethical and legal compliance, verifying accurate species identification, maintaining sample integrity during transport, and isolating high‐quality DNA or nuclei. While many of the challenges and solutions we discuss are broadly relevant, our regulatory and logistical examples are primarily from Europe. By synthesising practical guidance, we highlight the crucial importance of taxonomic expertise, proper vouchering and biobanking, rigorous cold‐chain management or alternative preservation methods, and emphasise adherence to packaging and shipping requirements for biological materials. We showcase examples spanning diverse regions, taxa and source materials, which underscore the importance of context‐specific strategies and internationally harmonised protocols, particularly for metadata reporting. Our recommendations aim to support both small‐scale projects and large initiatives, directing collective efforts to facilitate efficient sampling, vouchering and sample processing for future genomic studies.

The increasing demand for novel drug leads requires bioprospecting non-model taxa. Comparative genomics and correlative omics are a fast and efficient method for linking bioactive but genetically orphan natural products to their biosynthetic gene clusters (BGCs) and identifying potentially novel drug leads. Here we implement these approaches for the first systematic comparison of the BGC diversity in lichen-forming fungi (LFF) (comprising 20% of known fungi), prolific but underutilized producers of bioactive natural products. We first identified BGCs from all publicly available LFF genomes (111), encompassing 71 fungal genera and 23 families, and generated BGC similarity networks of each class. We recovered 5,541 BGCs grouped into 4,464 gene cluster families. We used mass spectrometry (MS) and correlative metabolomics to link five MS-identified metabolites – alectoronic acid, alpha-collatolic acid, evernic acid, stenosporic acid and perlatolic acid – to their putative BGCs. We subsequently used MS on an additional 80 species to explore the taxonomic breadth of common lichen compounds, uncovering a strong pattern between specific families and secondary metabolites. We found that (1) ~98% of the BGCs in LFF are putatively novel (uncharacterized to date), (2) lichen metabolic profiles contain a plethora of unidentified metabolites and (3) ribosomal peptide-related BGCs constitute about 20% of the LFF BGC landscape. Our study provides comprehensive insights into the BGC landscape of LFFs, highlighting unique, widespread and previously uncharacterized BGCs. We anticipate that the approach we describe will serve as a baseline for leveraging biosynthetic research in non-model organisms, inspiring further investigations into microbial dark matter.

Red Listing lichenized fungi: best practices and future prospects – ERRATUM - Volume 57 Issue 2

Dominican amber (15–20 Ma) and Mexican amber (15–23 Ma) are valuable sources of fossil epiphytic bryophytes, ferns, and lichens. Both ambers derive from resins of Hymenaea, a genus in the Fabaceae family still occurring in Mexico, Central America, and the Caribbean today. The amber inclusions provide rare glimpses into Miocene neotropical epiphyte communities in life-like preservation. In this study, we extend the fossil record of these communities and describe Frullania chiapasensis and Thysananthus patrickmuelleri, two new fossil species of leafy liverworts from Mexican amber. Frullania chiapasensis is the fourth representative of this genus from tropical amber. The genus Thysananthus is rather diverse in Dominican amber, and it is here newly recorded from Mexican amber. Additionally, we treat five new fossils at genus level, including one leafy liverwort (Lejeunea sp.) as well as three lichens from Dominican amber and one lichen from Mexican amber, all belonging to the extant genus Parmotrema. All four cryptogamic genera are common extant elements of tropical and subtropical forests. The new fossil evidence substantiates that Miocene neotropical cryptogamic communities were very similar to extant ones at generic level.

According to International Union for the Conservation of Nature (IUCN) guidelines, all species must be assessed against all criteria during the Red Listing process. For organismal groups that are diverse and understudied, assessors face considerable challenges in assembling evidence due to difficulty in applying definitions of key terms used in the guidelines. Challenges also arise because of uncertainty in population sizes (Criteria A, C, D) and distributions (Criteria A2/3/4c, B). Lichens, which are often small, difficult to identify, or overlooked during biodiversity inventories, are one such group for which specific difficulties arise in applying Red List criteria. Here, we offer approaches and examples that address challenges in completing Red List assessments for lichens in a rapidly changing arena of data availability and analysis strategies. While assessors still contend with far from perfect information about individual species, we propose practical solutions for completing robust assessments given the currently available knowledge of individual lichen life-histories.

The genus Xanthoparmelia includes several subcrustose, squamulose, small foliose, and small subfruticose species, primarily in the Southern Hemisphere. Here, we report on the first small foliose species lacking usnic acid in the genus occurring in the Holarctic. The species has been previously known as Lecanora olivascens Nyl., but subsequent studies of the morphology, secondary chemistry, and molecular data of the nuITS rDNA indicate that this species instead belongs to Xanthoparmelia. Consequently, the new combination Xanthoparmelia olivascens (Nyl.) V.J. Rico and G. Amo is proposed, and an epitype is designated here. We discuss the unique presence of a subcrustose Xanthoparmelia species lacking cortical usnic acid in the Northern Hemisphere. This species fits phylogenetically into a clade that was previously only known from the Southern Hemisphere, and hence represents another example of N-S disjunction in lichenized fungi.