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1.
MycoKeys ; 105: 21-47, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38694266

RESUMEN

Four species of the genus Sticta are described as new from Bolivia, based on morphological examination and phylogenetic analysis of the fungal ITS barcoding marker. Additionally, two species are reported as new to Bolivia (their identification confirmed by molecular data) and one previously reported species is confirmed by molecular data for the first time. Detailed morphological and anatomical descriptions are provided for all new species. Two of the new species, S.isidiolobulata Ossowska, B. Moncada, Lücking & Kukwa and S.madidiensis Ossowska, B. Moncada, Lücking & Kukwa belong to clade I, as defined in previous studies. In contrast, S.montepunkuensis Ossowska, B. Moncada, Lücking & Kukwa and S.macrolobata Ossowska, B. Moncada, Lücking & Kukwa, also described here as new to science, belong to clade III. Stictaisidiolobulata has an irregular to suborbicular thallus of medium size, with isidia developing into spathulate lobules, cyanobacterial photobiont and apothecia with entire to weakly-crenate margins. The large irregular thallus of the cyanobacteria-associated S.macrolobata has broad lobes, apothecia with verrucous to tomentose margins and cyphellae with raised margins, whereas S.madidiensis has a medium-sized, palmate to irregular thallus with a stipe, but without vegetative propagules and apothecia. Stictamontepunkuensis has large and irregular thalli with green algae as photobiont, apothecia with crenate to verrucous margins and urceolate cyphellae with a wide pore and a scabrid basal membrane. Two species, S.beauvoisii Delise and S.riparia Merc.-Díaz are reported as new to Bolivia (the latter also as new to South America) and belong to clade III. Stictatomentosa (Sw.) Ach., species confirmed from Bolivia by molecular data, belongs to clade II. Stictabeauvoisii is characterised by a smooth yellowish-brown upper surface with darker apices and abundant, marginal isidia and a brown lower surface with golden-chocolate brown primary tomentum and sparse, golden-brown rhizines. Stictariparia has a strongly branched thallus, with undulate lobes and abundant, marginal, palmate, grey to dark brown phyllidia and greyish-brown lower surface with the primary tomentum absent towards the margins. Stictatomentosa has palmate, bluish thalli with white cilia and abundant, submarginal apothecia and creamy-white lower surface with a sparse, white primary tomentum.

2.
Mol Phylogenet Evol ; 186: 107830, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37247703

RESUMEN

Phylogenetic approaches to macroevolution have provided unique insight into evolutionary relationships, ancestral ranges, and diversification patterns for many taxa. Similar frameworks have also been developed to assess how environmental and/or spatial variables shape species diversity and distribution patterns at different spatial/temporal scales, but studies implementing these are still scarce for many groups, including lichens. Here, we combine phylogeny-based ancestral range reconstruction and diversification analysis with community phylogenetics to reconstruct evolutionary origins and assess patterns of taxonomic and phylogenetic relatedness between island communities of the lichenized fungal genus Sticta in the Caribbean. Sampling was carried out in the Greater Antilles (Cuba, Jamaica, Dominican Republic, and Puerto Rico) and Lesser Antilles (Dominica, Guadeloupe, and Martinique). Data for six molecular loci were obtained for 64 candidate Caribbean species and used to perform both macroevolutionary phylogenetics, which also included worldwide taxa, and phylobetadiversity analyses, which emphasized island-level communities. Our work uncovered high levels of island endemism (∼59%) in Caribbean Sticta. We estimate initial colonization of the region occurred about 19 Mya from a South American ancestor. Reverse migration events by Caribbean lineages to South America were also inferred. We found no evidence for increased diversification rates associated with range expansion into the Caribbean. Taxonomic and phylogenetic turnover between island-level communities was most strongly correlated with environmental variation rather than with geographic distance. We observed less dissimilarity among communities from the Dominican Republic and Jamaica than between these islands and the Lesser Antilles/Puerto Rico. High levels of hidden diversity and endemism in Caribbean Sticta reaffirm that islands are crucial for the maintenance of global biodiversity of lichenized fungi. Altogether, our findings suggest that strong evolutionary links exist between Caribbean and South American biotas but at regional scales, species assemblages exhibit complex taxonomic and phylogenetic relationships that are determined by local environments and shared evolutionary histories.


Asunto(s)
Ascomicetos , Evolución Biológica , Filogenia , Región del Caribe , Biodiversidad , Ascomicetos/genética
3.
Mol Phylogenet Evol ; 168: 107380, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34999241

RESUMEN

We present the first broad molecular-phylogenetic revision of the lichenized family Gomphillaceae, based on 408 newly generated sequences of the mitochondrial SSU rDNA and nuclear LSU rDNA, representing 342 OTUs. The phylogenetic analysis of 20 out of the 28 currently accepted genera resulted in 48 clades. Twelve genera were resolved as monophyletic: Actinoplaca, Arthotheliopsis, Bullatina, Caleniopsis, Corticifraga, Gomphillus, Gyalectidium, Gyalidea, Jamesiella, Rolueckia, Rubrotricha, and Taitaia. Two genera resulted paraphyletic, namely Aulaxina (including Caleniopsis) and Asterothyrium (including Linhartia). Six genera were in part highly polyphyletic: Aderkomyces, Calenia, Echinoplaca, Gyalideopsis, Psorotheciopsis, and Tricharia. While ascoma morphology and anatomy has traditionally been considered as main character complex to distinguish genera, our study supported the notion that the characteristic asexual anamorph of Gomphillaceae, the so-called hyphophores, are diagnostic for most of the newly recognized clades. As a result, we recognize 26 new genus-level clades, three of which have names available (Microxyphiomyces, Psathyromyces, Spinomyces) and 23 that will require formal description as new genera. We also tested monophyly for 53 species-level names for which two or more specimens were sequenced: 27 were supported as monophyletic and representing a single species, 13 as monophyletic but with an internal topology suggesting cryptic speciation, four as paraphyletic, and nine as polyphyletic. These data suggest that species richness in the family is higher than indicated by the number of accepted names (currently 425); they also confirm that recently refined species concepts reflect species richness better than the broad concepts applied in Santesson's monograph. A divergence time analysis revealed that foliicolous Gomphillaceae diversified after the K-Pg-boundary and largely during the Miocene, a notion supported by limited data available for other common foliicolous lineages such as Chroodiscus (Graphidaceae), Pilocarpaceae, and Porinaceae. This contradicts recent studies suggesting that only macrofoliose Lecanoromycetes exhibit increased diversification rates in the Cenozoic.


Asunto(s)
Ascomicetos , Líquenes , Ascomicetos/genética , Secuencia de Bases , ADN Ribosómico/genética , Líquenes/genética , Filogenia , Análisis de Secuencia de ADN
4.
MycoKeys ; 92: 131-160, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36761317

RESUMEN

Six species of Sticta are described as new to science on the basis of material from Bolivia and supported by phylogenetic analysis of the fungal ITS barcoding marker. The species were resolved in all three of the clades (I, II, III) widespread and common in the Neotropics, as defined in an earlier study on the genus. Comparison with material from neighbouring countries (i.e. Colombia, Ecuador, Peru) suggests that these new species may be potentially endemic to the Bolivian Yungas ecoregion. For each species, a detailed morphological and anatomical description is given. Stictaamboroensis Ossowska, Kukwa, B. Moncada & Lücking is a medium-sized green-algal species with laminal to submarginal apothecia with hirsute margins and with light to dark brown lower tomentum. Stictaaymara Ossowska, Kukwa, B. Moncada, Flakus, Rodriguez-Flakus & Lücking is a comparatively small cyanobacterial taxon with Nostoc as photobiont, laminal, richly branched, aggregate isidia and a golden to chocolate-brown lower tomentum. The medium-sized, cyanobacterial S.bicellulata Ossowska, Kukwa, B. Moncada & Lücking has cyanobacterial photobiont, bicellular ascospores, apothecia with white to golden-brown hairs on the margins, K+ violet apothecial margin (ring around disc) and epihymenium and a white to dark brown lower tomentum. In contrast, the green-algal species, S.carrascoensis Ossowska, Kukwa, B. Moncada & Lücking is characterised by its large size, apothecia with dark brown hairs on the margins and a yellow medulla. The cyanobacterial S.catharinae Ossowska, B. Moncada, Kukwa, Flakus, Rodriguez-Flakus & Lücking forms stipitate thalli with Nostoc as photobiont, abundant, laminal to submarginal apothecia and a golden-brown lower tomentum. Finally, the cyanobacterial S.pseudoimpressula Ossowska, Kukwa, B. Moncada & Lücking produces laminal apothecia with an orange-yellow line of pruina along the margins which reacts K+ carmine-red. In addition to the six new Bolivian taxa, the cyanobacterial S.narinioana B. Moncada, Ossowska & Lücking is described as new from Colombia and it represents the closely-related sister species of the Bolivian S.aymara; it differs from the latter largely in the marginal instead of laminal isidia.

5.
Mol Phylogenet Evol ; 150: 106860, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32473336

RESUMEN

Species in the fungal genus Sticta form symbiotic associations primarily with either green algae or cyanobacteria, but tripartite associations or photosymbiodemes involving both types of photobionts occur in some species. Sticta is known to associate with green algae in the genus Symbiochloris. However, previous studies have shown that algae from other genera, such as Heveochlorella, may also be suitable partners for Sticta. We examined the diversity of green algal partners in the genus Sticta and assessed the patterns of association between the host fungus and its algal symbiont. We used multi-locus sequence data from multiple individuals collected in Australia, Cuba, Madagascar, Mauritius, New Zealand, Reunion and South America to infer phylogenies for fungal and algal partners and performed tests of congruence to assess coevolution between the partners. In addition, event-based methods were implemented to examine which cophylogenetic processes have led to the observed association patterns in Sticta and its green algal symbionts. Our results show that in addition to Symbiochloris, Sticta associates with green algae from the genera Chloroidium, Coccomyxa, Elliptochloris and Heveochlorella, the latter being the most common algal symbiont associated with Sticta in this study. Geography plays a strong role in shaping fungal-algal association patterns in Sticta as mycobionts associate with different algal lineages in different geographic locations. While fungal and algal phylogenies were mostly congruent, event-based methods did not find any evidence for cospeciation between the partners. Instead, the association patterns observed in Sticta and associated algae, were largely explained by other cophylogenetic events such as host-switches, losses of symbiont and failure of the symbiont to diverge with its host. Our results also show that tripartite associations with green algae evolved multiple times in Sticta.


Asunto(s)
Ascomicetos/clasificación , Chlorophyta/clasificación , Ascomicetos/genética , Chlorophyta/genética , Tipificación de Secuencias Multilocus , Filogenia , ARN Ribosómico 18S/química , ARN Ribosómico 18S/clasificación , ARN Ribosómico 18S/genética , Simbiosis
6.
Front Microbiol ; 11: 398, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32265864

RESUMEN

The High Andean Paramo ecosystem is a unique neotropical mountain biome considered a diversity and evolutionary hotspot. Lichens, which are complex symbiotic structures that contain diverse commensal microbial communities, are prevalent in Paramos. There they play vital roles in soil formation and mineral fixation. In this study we analyzed the microbiomes of seven lichen genera in Colombian Paramos using 16S rRNA gene amplicon sequencing and provide the first description of the bacterial communities associated with Cora and Hypotrachyna lichens. Paramo lichen microbiomes varied in diversity indexes and number of OTUs, but were composed predominantly by the phyla Acidobacteria, Actinobacteria, Bacteroidetes, Cyanobacteria, Proteobacteria, and Verrucomicrobia. In the case of Cora and Cladonia, the microbiomes were distinguished based on the identity of the lichen host. While the majority of the lichen-associated microorganisms were not present in all lichens sampled, sixteen taxa shared among this diverse group of lichens suggest a core lichen microbiome that broadens our concept of these symbiotic structures. Additionally, we identified strains producing compounds active against clinically relevant microbial strains. These results indicate that lichen microbiomes from the Paramo ecosystem are diverse and host-specific but share a taxonomic core and can be a source of new bacterial taxa and antimicrobials.

7.
Sci Rep ; 9(1): 8968, 2019 06 20.
Artículo en Inglés | MEDLINE | ID: mdl-31222061

RESUMEN

In the age of next-generation sequencing, the number of loci available for phylogenetic analyses has increased by orders of magnitude. But despite this dramatic increase in the amount of data, some phylogenomic studies have revealed rampant gene-tree discordance that can be caused by many historical processes, such as rapid diversification, gene duplication, or reticulate evolution. We used a target enrichment approach to sample 400 single-copy nuclear genes and estimate the phylogenetic relationships of 13 genera in the lichen-forming family Lobariaceae to address the effect of data type (nucleotides and amino acids) and phylogenetic reconstruction method (concatenation and species tree approaches). Furthermore, we examined datasets for evidence of historical processes, such as rapid diversification and reticulate evolution. We found incongruence associated with sequence data types (nucleotide vs. amino acid sequences) and with different methods of phylogenetic reconstruction (species tree vs. concatenation). The resulting phylogenetic trees provided evidence for rapid and reticulate evolution based on extremely short branches in the backbone of the phylogenies. The observed rapid and reticulate diversifications may explain conflicts among gene trees and the challenges to resolving evolutionary relationships. Based on divergence times, the diversification at the backbone occurred near the Cretaceous-Paleogene (K-Pg) boundary (65 Mya) which is consistent with other rapid diversifications in the tree of life. Although some phylogenetic relationships within the Lobariaceae family remain with low support, even with our powerful phylogenomic dataset of up to 376 genes, our use of target-capturing data allowed for the novel exploration of the mechanisms underlying phylogenetic and systematic incongruence.


Asunto(s)
Ascomicetos/clasificación , Ascomicetos/genética , Evolución Molecular , Filogenia , Evolución Biológica , Código de Barras del ADN Taxonómico , Bases de Datos Genéticas
8.
Mol Phylogenet Evol ; 126: 58-73, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29656104

RESUMEN

A major challenge to evolutionary biologists is to understand how biodiversity is distributed through space and time and across the tree of life. Diversification of organisms is influenced by many factors that act at different times and geographic locations but it is still not clear which have a significant impact and how drivers interact. To study diversification, we chose the lichen genus Sticta, by sampling through most of the global range and producing a time tree. We estimate that Sticta originated about 30 million years ago, but biogoegraphic analysis was unclear in estimating the origin of the genus. Furthermore, we investigated the effect of dispersal ability finding that Sticta has a high dispersal rate, as collections from Hawaii showed that divergent lineages colonized the islands at least four times. Symbiont interactions were investigated using BiSSE to understand if green-algal or cyanobacterial symbiont interactions influenced diversification, only to find that the positive results were driven almost completely by Type I error. On the other hand, another BiSSE analysis found that an association with Andean tectonic activity increases the speciation rate of species.


Asunto(s)
Ascomicetos/clasificación , Biodiversidad , Filogenia , Evolución Biológica , Extinción Biológica , Líquenes/clasificación , Filogeografía , Factores de Tiempo
9.
NOVA publ. cient ; 13(23): 65-72, ene.-jun. 2015. ilus, tab
Artículo en Español | LILACS, COLNAL | ID: lil-759076

RESUMEN

Objetivo. Determinar la actividad antimicrobiana de extractos de diferentes polaridades de las especies de Everniastrum columbiense, Flavopunctelia flaventor, Parmotrema simulans, Ramalina celastri, Teloschistes exilis y Usnea sp., recolectadas en el margen occidental de la cuenca alta del Río Bogotá, a los 05° 07' 23,4"N y 73° 39' 10,5"W; frente a los microorganismos Staphylococcus aureus y Klebsiella pneumoniae. Materiales y métodos. Se utilizó el método de difusión en gel por perforación en placa. Resultados. Los extractos de Flavopunctelia flaventor, Everniastrum columbiense, Parmotrema simulans, Usnea Sp y Ramalina celastri, presentaron actividad antibacteriana frente a Staphylococcus aureus. Y los extractos de Flavopunctelia flaventor, Usnea Sp. y Ramalina celastri, presentaron actividad antibacteriana frente a Klebsiella pneumoniae.


To determine the antimicrobial activity of extracts of different polarities species Everniastrum columbiense, flaventor Flavopunctelia, Parmotrema simulans, Ramalina celastri, Teloschistes exilis and Usnea sp, collected on the western margin of the basin alta of Río Bogotá, to 05. ° 07 '23.4 "N and 73 ° 39' 10.5" W; against microorganisms Staphylococcus aureus and Klebsiella pneumoniae. Materials and methods. Diffusion method was used in gel plate by drilling. Results: Extracts of Flavopunctelia flaventor, Everniastrum columbiense, Parmotrema simulans, Usnea Sp and Ramalina celastri showed antibacterial activity against Staphylococcus aureus with antibacterial. And extracts Flavopunctelia flaventor, Usnea Sp and Ramalina celastri showed antibacterial activity against Klebsiella pneumoniae.


Asunto(s)
Humanos , Botánica , Hongos , Líquenes , Antiinfecciosos
10.
Proc Natl Acad Sci U S A ; 111(30): 11091-6, 2014 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-24982168

RESUMEN

The number of Fungi is estimated at between 1.5 and 3 million. Lichenized species are thought to make up a comparatively small portion of this figure, with unrecognized species richness hidden among little-studied, tropical microlichens. Recent findings, however, suggest that some macrolichens contain a large number of unrecognized taxa, increasing known species richness by an order of magnitude or more. Here we report the existence of at least 126 species in what until recently was believed to be a single taxon: the basidiolichen fungus Dictyonema glabratum, also known as Cora pavonia. Notably, these species are not cryptic but morphologically distinct. A predictive model suggests an even larger number, with more than 400 species. These results call into question species concepts in presumably well-known macrolichens and demonstrate the need for accurately documenting such species richness, given the importance of these lichens in endangered ecosystems such as paramos and the alarming potential for species losses throughout the tropics.


Asunto(s)
Basidiomycota/clasificación , Líquenes/clasificación
11.
Rev Biol Trop ; 62(1): 257-72, 2014 Mar.
Artículo en Español | MEDLINE | ID: mdl-24912357

RESUMEN

Colombia is a megadiverse country, but with a substantial gap in the taxonomic and ecological knowledge of fungi and lichens. Thus, the objective of the present study was an ecogeographical analysis of the Sticta species in Colombia. The data included macrodistribution (with respect to mountain ranges and life zones) and microhabitat preferences (light, substrate) and were obtained from field work and herbarium collection labels (completed by comparison with modern geographic and vegetation maps), for 103 species of Sticta currently recognized in Colombia (plus seven additional biotypes with different photobionts or reproductive mode). Using non-metric multidimensional scaling (NMS), correlations between ecogeographical variables and species were established, and ecotypes were delimited. Colombian species of Sticta showed distinct distribution patterns relative to altitude, mountain ranges, life zones, as well as light exposure and substrate, forming several distinct groups. Cyanobacterial species tend to have wider distribution ranges than green algal species. We concluded that the orogeny of the Northern Andes substantially affected speciation of the genus Sticta and its ecogeographical differentiation.


Asunto(s)
Ascomicetos/clasificación , Colombia , Ecosistema , Geografía , Filogenia
12.
Rev. biol. trop ; 62(1): 266-281, ene.-mar. 2014. tab
Artículo en Español | LILACS | ID: lil-715429

RESUMEN

Colombia is a megadiverse country, but with a substantial gap in the taxonomic and ecological knowledge of fungi and lichens. Thus, the objective of the present study was an ecogeographical analysis of the Sticta species in Colombia. The data included macrodistribution (with respect to mountain ranges and life zones) and microhabitat preferences (light, substrate) and were obtained from field work and herbarium collection labels (completed by comparison with modern geographic and vegetation maps), for 103 species of Sticta currently recognized in Colombia (plus seven additional biotypes with different photobionts or reproductive mode). Using non-metric multidimensional scaling (NMS), correlations between ecogeographical variables and species were established, and ecotypes were delimited. Colombian species of Sticta showed distinct distribution patterns relative to altitude, mountain ranges, life zones, as well as light exposure and substrate, forming several distinct groups. Cyanobacterial species tend to have wider distribution ranges than green algal species. We concluded that the orogeny of the Northern Andes substantially affected speciation of the genus Sticta and its ecogeographical differentiation.


Colombia es un país megadiverso, pero con una ausencia significativa en el conocimiento de la taxonomía y ecología de hongos y líquenes. Por lo tanto, el objetivo del presente estudio era un análisis ecogeográfico de las especies de Sticta de Colombia. Los datos incluyeron la macrodistribución (con respeto a las cordilleras y zonas de vida) y preferencias de microhabitat (luz, sustrato) y fueron obtenidos mediante trabajo de campo y en el herbario (complemetados con mapas modernos de geografía y vegetación), para 103 especies actualmente reconocidas en Colombia (más siete biotipos con diferentes fotobiontes o modo de reproducción). Se elaboró un análisis de ordenación usando la técnica de escalamiento multidimensional no métrico (NMS), para establecer correlaciones entre variables ecogeográficas y las especies y para definir ecotipos. Las especies de Sticta en Colombia presentan patrones de distribución relativos a la altitud, las zonas de vida y la ubicación en las cordilleras, tanto como luz y sustrato, formando varios grupos distintos. Las especies con ciano-bionte tienen un rango de distribución más amplio que las especies con fotobionte verde. Concluimos que la orogenia de los Andes afectó significativamente la especiación del género Sticta y su diferenciación ecogeográfica.


Asunto(s)
Ascomicetos/clasificación , Colombia , Ecosistema , Geografía , Filogenia
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