Filogeografía y biología de líquenes Antártidos

Los líquenes son los organismos macroscópicos dominantes en los ecosistemas terrestres de la Antártida. Con casi dos siglos de historia, el estudio de la biota liquénica antártica ha sufrido un nuevo impulso con la irrupción de las técnicas basadas en el ADN, lo que ha permitido incrementar las estimas de hongos liquenizados en la Antártida por encima de las 500 especies (Øvstedal y Lewis Smith 2011). Pese a su abundancia, poco se sabe aún sobre su origen. Alrededor de un 40% de las especies muestra un patrón de distribución bipolar o anfitropical, mientras que un 30% son endemismos antárticos (Øvstedal y Lewis Smith 2001). Durante el siglo XX, la mayoría de autores aceptaron un origen temporal dual, por el que las especies endémicas tendrían un origen relicto, anterior al Pleistoceno, y las especies bipolares (y cosmopolitas) habrían colonizado la Antártida en tiempos más recientes (p. ej. Lamb 1948, 1970; Dodge 1964; Seppelt 1995). Objetivos: La presente tesis doctoral tiene como objetivo principal contribuir al conocimiento de la diversidad liquénica en la Antártida y a dilucidar su origen, enfocándose en estudios filogeográficos de especies endémicas y de especies con distribución bipolar..

Checklist of epiphytic lichens on "Quercus ilex" subsp. "rotundifolia" from Vall d’Albaida (Valencia, Spain)

Se presenta un catálogo de 55 líquenes epífitos y 2 hongos liquenícolas que crecen en la corteza de Quercus ilex subsp. rotundifolia en unode los enclaves más orientales del Sistema Bético peninsular en donde el aprovechamiento agrícola del territorio ha sido y es muy intensivo.A catalogue of 55 lichens growing on bark of holm-oak (Quercus ilex subsp. rotundifolia) and 2 lichenicolous fungi is compiled from oneof the most eastern areas of Betic Range. The area is characterized by an intensive agriculture since long

Inocybe ochrogaleata sp. nov., un nouvel Inocybe récolté dans la péninsule Ibérique

The authors describe Inocybe ochrogaleata, a new Inocybe collected under Quercus ilex and Pinus halepensis accompanied by Cistus (among others Cistus albidus) in the Huétor Santillán natural park, the Sierras Tejeda, Almijara and Alhama (Andalusia) and Quatretonda in the Valencia region (Spain). A discussion on genetically and morphologically similar taxa is proposed

The effect of agriculture management and fire on epiphytic lichens on holm oak trees in the eastern Iberian Peninsula

Abstract: For a long time, agriculture and recurrent fires have been the main factors promoting diversity changes in Mediterranean areas. We examined the effect of irrigated and non-irrigated crops and fires on the epiphytic lichen diversity of holm oak trees in the Vall d'Albaida region (Valencia, Spain). Lichen diversity was studied by calculating the LDV (Lichen Diversity Value) and the proportion of functional groups. No significant differences were observed between areas located near irrigated or non-irrigated crops. Fire-affected areas tended to harbour lower LDV and species richness than those influenced by agriculture. By using lichen functional groups, it has been shown that eutrophication tolerance, substratum pH affinity and, to some extent, thallus growth form are the main factors driving epiphytic lichen diversity in this rural area

Phylogeography of Ramalina farinacea (Lichenized Fungi, Ascomycota) in the Mediterranean Basin, Europe, and Macaronesia

Ramalina farinacea is an epiphytic lichen-forming fungus with a broad geographic distribution, especially in the Northern Hemisphere. In the eighties of the last century, it was hypothesized that R. farinacea had originated in the Macaronesian–Mediterranean region, with the Canary Islands as its probable southernmost limit, and thereafter it would have increased its distribution area. In order to explore the phylogeography of this emblematic lichen, we analyzed 120 thalli of R. farinacea collected in 38 localities distributed in temperate and boreal Europe, the Western Mediterranean Basin, and several Macaronesian archipelagos in the Atlantic Ocean. Data from two nuclear markers (nrITS and uid70) of the mycobiont were obtained to calculate genetic diversity indices to infer the phylogenies and haplotype networks and to investigate population structure. In addition, dating analysis was conducted to provide a valuable hypothesis of the timing of the origin and diversification of R. farinacea and its close allies. Our results highlight that phylogenetic species circumscription in the “Ramalina farinacea group” is complex and suggests that incomplete lineage sorting is at the base of conflicting phylogenetic signals. The existence of a high number of haplotypes restricted to the Macaronesian region, together with the diversification of R. farinacea in the Pleistocene, suggests that this species and its closest relatives originated during relatively recent geological times and then expanded its range to higher latitudes. However, our data cannot rule out whether the species originated from the Macaronesian archipelagos exclusively or also from the Mediterranean Basin. In conclusion, the present work provides a valuable biogeographical hypothesis for disentangling the evolution of this epiphytic lichen in space and time

Are recently deglaciated areas at both poles colonised by the same bacteria?

Polar glacier forefields offer an unprecedented framework for studying community assembly processes in regions that are geographically and climatically isolated. Through amplicon sequence variant (ASV) inference, we compared the composition and structure of soil bacterial communities from glacier forefields in Iceland and Antarctica to assess overlap between communities and the impact of established cryptogamic covers on the uniqueness of their taxa. These pioneer microbial communities were found to share only 8% of ASVs and each taxonomic group's contribution to the shared ASV data subset was heterogeneous and independent of their relative abundance. Although the presence of ASVs specific to one glacier forefield and/or different cryptogam cover values confirms the existence of habitat specialist bacteria, our data show that the influence of cryptogams on the edaphic bacterial community structure also varied also depending on the taxonomic group. Hence, the establishment of distinct cryptogamic covers is probably not the only factor driving the uniqueness of bacterial communities at both poles. The structure of bacterial communities colonising deglaciated areas seems also conditioned by lineage-specific limitations in their dispersal capacity and/or their establishment and persistence in these isolated and hostile regions

Novel lichen-dominated hypolithic communities in the Namib Desert

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.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. DC acknowledges the financial support of the University of Pretoria and the National Research Foundation of South Africa. AV was supported by the project “CLU-2019–05 – IRNASA/CSIC Unit of Excellence,” funded by the Junta de Castilla y León and co-financed by the European Union (ERDF “Europe drives our growth”). This work was supported by grants CTM2015-64728-C2- 2-R (MINECO/FEDER, EU) and PID2019-105469RB-C22 (MICINN).http://link.springer.com/journal/248am2022BiochemistryGeneticsMicrobiology and Plant Patholog

Puccinia antirrhini Dietel & Holway, un hongo pucciniomiceto parásito de Antirrhinum barrelieri Boreau subsp. barrelieri

Fecha de impresión: 2014[CA] Se cita per primera vegada al territori valencià Puccinia antirrhini Dietel & Holway, un fong pucciniomicet paràsit d’Antirrhinum barrelieri Boreau subsp. barrelieri. S’hi al·ludeix a les publicacions més rellevants referides a aquest grup de fongs paràsits al territori valencià.[ES] Se cita por primera vez para el territorio valenciano Puccinia antirrhini Dietel & Holway, un hongo pucciniomiceto parásito de Antirrhinum barrelieri Boreau subsp. barrelieri. Se hace alusión a las publicaciones más relevantes referentes a este grupo de hongos parásitos en el territorio valenciano.[EN] A compendium of the most important papers dealing with these parasitic fungi in this region is also included.Peer reviewe