It has long been assumed that lichen-forming fungi have very large distribution ranges, and that endemic species are rare in this group of organisms. This is likely a consequence of the “everything small is everywhere” paradigm that has been traditionally applied to cryptogams. However, the description of numerous endemic species over the last decades, many of them in oceanic islands, is challenging this view. In this study, we provide another example, Xanthoparmelia ramosae, a species that is described here as new to science on the basis of morphological, chemical, and macroclimatic data, and three molecular markers (ITS rDNA, nuLSU rDNA, and mtSSU). The new species is endemic to the island of Gran Canaria but clusters into a clade composed exclusively of specimens collected in Eastern Africa, a disjunction that is here reported for the first time in lichen-forming fungi. Through the use of dating analysis, we have found that Xanthoparmelia ramosae diverged from its closely related African taxa in the Pliocene. This result, together with the reproductive strategy of the species, points to the Relict theory as a likely mechanism behind the disjunction, although the large gap in lichenological knowledge in Africa makes this possibility hard to explore any further.

Cyanobacteria, known for their remarkable adaptability, are a diverse group of oxygenic photoautotrophic organisms found in various habitats worldwide. While their presence in aquatic ecosystems has been extensively studied, research on terrestrial and aerophytic cyanobacteria remains relatively limited, particularly concerning their taxonomic diversity and molecular characteristics. In this study, utilizing morphological and molecular data derived from the 16S rRNA gene, we unveiled and described two new species of filamentous cyanobacteria growing epiphytically on Laurus novocanariensis in the laurel forest (laurisilva) of the Canary Islands. The first species, Brasilonema novocanariensis sp. nov., belongs to a genus of aerophytic and subaerophytic nostocalean cyanobacteria. The second, Rhizonema melkonianarum sp. nov., belongs to the genus Rhizonema. The discovery of a new species of Brasilonema from the Canary Islands related to species initially found on the opposite side of the Atlantic Ocean, and recently in Asia, Europe, and Portugal, raises questions about their dispersal mechanisms, whether through natural means or human-mediated processes, prompting the need for future studies to investigate these propagation patterns. In the case of Rhizonema melkonianarum sp. nov., the transition from adapting to a basidiolichen host to inhabiting the phyllosphere of angiosperms raises ecological and evolutionary adaptation questions regarding cyanobacterial adaptability and their ecological roles in diverse habitats. This research expands our understanding of the diversity and geographic distribution of these terrestrial phyllosphere-associated cyanobacteria.

This work presents the set of preliminary studies for the conservation and restoration of the fountain in plaza Weyler (Santa Cruz de Tenerife). The working methodology is interdisciplinary and aims to identify and characterize the construction materials, along with the products generated in the alteration processes, to determine the mechanisms and causes of deterioration. Two marbles of different origins belonging to two construction phases of the aforementioned square, a traditional mortar of limestone and sand as mortar, calcareous concretions resulting from filtrations and biological colonization by microalgae have been identified. A method of non-invasive analysis has been used to determine the extent of certain pathologies. In this way, it will be possible to define a specific proposal of action to deal with the pathologies affecting this cultural asset.

A total of 96 strains of Nostocales (Cyanobacteria) were established from the phyllosphere of the laurel forests in the Canary Islands (Spain) and the Azores (Portugal) using enrichment media lacking combined nitrogen. The strains were characterized by light microscopy and SSU rRNA gene comparisons. Morphologically, most strains belonged to two different morphotypes, termed “Nostoc-type” and “Tolypothrix-type”. Molecular phylogenetic analysis of 527 SSU rRNA gene sequences of cyanobacteria (95 sequences established during this study plus 392 sequences from Nostocales and 40 sequences from non-heterocyte-forming cyanobacteria retrieved from the databases) revealed that none of the SSU rRNA gene sequences from the phyllosphere of the laurel forests was identical to a database sequence. In addition, the genetic diversity of the isolated strains was high, with 42 different genotypes (44% of the sequences) recognized. Among the new genotypes were also terrestrial members of the genus Nodularia as well as members of the genus Brasilonema. It is concluded that heterocyte-forming cyanobacteria represent a component of the phyllosphere that is still largely undersampled in subtropical/tropical forests.

Environmental and human factors are inducing a drastic decline in many marine algae in regions with a high floristic richness as in the Canary Islands. Simultaneously, undescribed algal species continue to be discovered, suggesting a probable loss in diversity, before being properly identified and catalogued. Turf-forming Gelidiales occur in marine littoral communities from tropical to warm temperate regions and are challenging to identify correctly because of their small size and simple morphology. In the present study, we combined morphological and molecular phylogenetics methods to study a turf-forming species of the genus Pterocladiella from the Canary Islands (NE Atlantic). Both cox1 and rbcL gene analyses revealed a novel species described here, Pterocladiella canariensis sp. nov. The new species has no single unique morphological feature, but it is different by a distinctive combination of attributes, namely, minute size less than 18 mm in height, ribbon-like erect axes, small polygonal cortical cells, cystocarp circular in outline with placental tissue attached to the floor, spermatangial sori with sterile margins with spermatangia simultaneously formed on both sides of the blade, and tetrasporangia arranged in V-shaped rows. Phylogenies inferred from cox1 and concatenated genes (cox1 + rbcL) suggest a link to only two Pterocladiella species endemic to South Africa and Madagascar; nevertheless, the rbcL gene establishes P. canariensis as the earliest divergent lineage of the genus.