ABSTRACT
DNA barcoding is a powerful method for the identification of lichenized fungi groups for which the diversity is already well-represented in nucleotide databases, and an accurate, robust taxonomy has been established. However, the effectiveness of DNA barcoding for identification is expected to be limited for understudied taxa or regions. One such region is Antarctica, where, despite the importance of lichens and lichenized fungi identification, their genetic diversity is far from characterized. The aim of this exploratory study was to survey the lichenized fungi diversity of King George Island using a fungal barcode marker as an initial identification tool. Samples were collected unrestricted to specific taxa in coastal areas near Admiralty Bay. Most samples were identified using the barcode marker and verified up to the species or genus level with a high degree of similarity. A posterior morphological evaluation focused on samples with novel barcodes allowed for the identification of unknown Austrolecia, Buellia, and Lecidea s.l. species. These results contribute to better represent the lichenized fungi diversity in understudied regions such as Antarctica by increasing the richness of the nucleotide databases. Furthermore, the approach used in this study is valuable for exploratory surveys in understudied regions to guide taxonomic efforts towards species recognition and discovery.
ABSTRACT
The ventral surfaces of translucent rocks from hot desert pavements often harbor hypolithic microbial communities, which are mostly dominated by cyanobacteria. The Namib Desert fog belt supports extensive hypolithic colonization of quartz rocks, which are also colonized by lichens on their dorsal surfaces. Here, we aim to evaluate whether lichens colonize the ventral surface of the rocks (i.e., show hypolithic lifestyle) and compare the bacterial composition of these coastal hypolithic communities with those found inland. Fungal DNA barcoding and fungal and bacterial Illumina metabarcoding were combined with electron microscopy to characterize the composition and spatial structure of hypolithic communities from two (coastal and inland) areas in the Namib Desert. We report, for the first time, the structure and composition of lichen-dominated hypolithic communities found in the coastal zone of the Namib Desert with extensive epilithic lichen cover. Lichen modified areoles with inverted morphology of the genus Stellarangia (three lineages) and Buellia (two lineages) were the main components of these hypolithic communities. Some of these lineages were also found in epilithic habitats. These lichen-dominated hypolithic communities differed in structural organization and bacterial community composition from those found in inland areas. The hypolithic lichen colonization characterized here seems not to be an extension of epilithic or biological soil crust lichen growths but the result of specific sublithic microenvironmental conditions. Moisture derived from fog and dew could be the main driver of this unique colonization.
Subject(s)
Cyanobacteria , Lichens , Cyanobacteria/genetics , Desert Climate , Ecosystem , Soil MicrobiologyABSTRACT
Several buellioid specimens were collected from South Korea during field surveys and two new species are described based on morphology, chemistry, and molecular phylogeny. Buellia boseongensis sp. nov. is similar to B. polyspora but differs in having a UV + orange thallus and cryptolecanorine apothecia. Sculptolumina coreana sp. nov., resembles S. japonica, but differs in having a smooth entire continuous thallus, which reacts K-, a narrower excipulum, thicker epihymenium, narrower subhymenium, and in containing secondary metabolites other than flavo-obscurin and myeloconone. A key to the buellioid lichens reported from Korea is also presented.
ABSTRACT
Several buellioid specimens were collected from South Korea during field surveys and two new species are described based on morphology, chemistry, and molecular phylogeny. Buellia boseongensis sp. nov. is similar to B. polyspora but differs in having a UV + orange thallus and cryptolecanorine apothecia. Sculptolumina coreana sp. nov., resembles S. japonica, but differs in having a smooth entire continuous thallus, which reacts K–, a narrower excipulum, thicker epihymenium, narrower subhymenium, and in containing secondary metabolites other than flavo-obscurin and myeloconone. A key to the buellioid lichens reported from Korea is also presented.
Subject(s)
Chemistry , Korea , Lichens , PhylogenyABSTRACT
The paper describes identification of new microlichen (Sculptolumina japonica) in South Korea. A detailed taxonomic description and comments are presented for the taxa studied. Lichen genus Sculptolumina is reported for the first time for this country.
ABSTRACT
The paper describes identification of new microlichen (Sculptolumina japonica) in South Korea. A detailed taxonomic description and comments are presented for the taxa studied. Lichen genus Sculptolumina is reported for the first time for this country.
Subject(s)
Lichens , Republic of KoreaABSTRACT
CO2 exchange and fluorescence yield of the crustose lichen Buellia frigida were measured in situ by means of a CO2 porometer and a PAM-2000, a newly developed portable fluorescence system. The pulse amplitude modulation system of the PAM-2000 allows measurements in the field under ambient light, temperature and moisture conditions without dark adaptation of the sample. CO2 exchange and fluorescence measurements were well correlated when measured under natural conditions in continental Antarctica during a drying cycle of melt-water-soaked lichen thalli. It was shown that the fluorescence parameter ΔF/Fm' is a measure of the photosynthetic activity of the lichen. It proved possible, using the PAM-2000, to differentiate the physiological performance of the thallus centre and the marginal lobes. The distribution of water in the thallus during a drying cycle was shown to be inhomogeneous. The photosynthetic rates of B. frigida calculated on an area basis are comparatively high and indicate that this lichen is well adapted to its habitat conditions in this part of continental Antarctica.
