Global diversity and geography of soil fungi Tedersoo, Leho; Bahram, Mohammad; Põlme, Sergei ...
Science (American Association for the Advancement of Science),
11/2014, Letnik:
346, Številka:
6213
Journal Article
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Fungi play major roles in ecosystem processes, but the determinants of fungal diversity and biogeographic patterns remain poorly understood. Using DNA metabarcoding data from hundreds of globally ...distributed soil samples, we demonstrate that fungal richness is decoupled from plant diversity. The plant-to-fungus richness ratio declines exponentially toward the poles. Climatic factors, followed by edaphic and spatial variables, constitute the best predictors of fungal richness and community composition at the global scale. Fungi show similar latitudinal diversity gradients to other organisms, with several notable exceptions. These findings advance our understanding of global fungal diversity patterns and permit integration of fungi into a general macroecological framework. Assessing fungal diversity worldwideFungi are hyperdiverse but poorly known, despite their ecological and economic impacts. Tedersoo et al. collected nearly 15,000 topsoil samples from 365 sites worldwide and sequenced their genomes (see the Perspective by Wardle and Lindahl). Overall, they found a striking decline in fungal species richness with distance from the equator. For some specialist groups though, diversity depended more on the abundance of host plants than host diversity or geography. The findings reveal a huge gap between known and described species and the actual numbers of distinct fungi in the world's soils.Science, this issue 10.1126/science.1256688; see also p. 1052
This study presents
Paxilloboletus
gen. nov., a new lamellate bolete genus represented by two tropical African species,
Paxilloboletus africanus
sp. nov. and
Paxilloboletus latisporus
sp. nov. ...Although the new taxa strongly resemble
Paxillus
(Paxillaceae), they lack clamp connections and form a separate generic clade within the Boletaceae phylogeny. The new species are lookalikes, morphologically only separable by their spore morphology. Descriptions and illustrations of the new genus and new species are given, as well as comments on ecology, distribution, and morphological differences with other gilled Boletaceae.
Our understanding of fungal diversity is far from complete. Species descriptions generally focus on morphological features, but this approach may underestimate true diversity. Using the morphological ...species concept, Hesperomyces virescens (Ascomycota, Laboulbeniales) is a single species with global distribution and wide host range. Since its description 120 years ago, this fungal parasite has been reported from 30 species of ladybird hosts on all continents except Antarctica. These host usage patterns suggest that H. virescens could be made up of many different species, each adapted to individual host species. Using sequence data from three gene regions, we found evidence for distinct clades within Hesperomyces virescens, each clade corresponding to isolates from a single host species. We propose that these lineages represent separate species, driven by adaptation to different ladybird hosts. Our combined morphometric, molecular phylogenetic and ecological data provide support for a unified species concept and an integrative taxonomy approach.
Fungal species identities are often based on morphological features, but current molecular phylogenetic and other approaches almost always lead to the discovery of multiple species in single ...morpho-species. According to the morphological species concept, the ant-parasitic fungus Rickia wasmannii (Ascomycota, Laboulbeniales) is a single species with pan-European distribution and a wide host range. Since its description, it has been reported from ten species of Myrmica (Hymenoptera, Formicidae), of which two belong to the rubra-group and the other eight to the phylogenetically distinct scabrinodis-group. We found evidence for R. wasmannii being a single phylogenetic species using sequence data from two loci. Apparently, the original morphological description (dating back to 1899) represents a single phylogenetic species. Furthermore, the biology and host-parasite interactions of R. wasmannii are not likely to be affected by genetic divergence among different populations of the fungus, implying comparability among studies conducted on members of different ant populations. We found no differences in total thallus number on workers between Myrmica species, but we did observe differences in the pattern of thallus distribution over the body. The locus of infection is the frontal side of the head in Myrmica rubra and M. sabuleti whereas in M. scabrinodis the locus of infection differs between worker ants from Hungary (gaster tergites) and the Netherlands (frontal head). Possible explanations for these observations are differences among host species and among populations of the same species in (i) how ant workers come into contact with the fungus, (ii) grooming efficacy, and (iii) cuticle surface characteristics.
In this paper we present an updated checklist of thallus-forming Laboulbeniomycetes (Ascomycota, Pezizomycotina), that is, the orders Herpomycetales and Laboulbeniales, from Belgium and the ...Netherlands. Two species are newly described based on morphology, molecular data (ITS, LSU ribosomal DNA) and ecology (host association). These are
Hesperomyces halyziae
on
Halyzia sedecimguttata
(Coleoptera, Coccinellidae) from both countries and
Laboulbenia quarantenae
on
Bembidion biguttatum
(Coleoptera, Carabidae) from Belgium. In addition, nine new country records are presented. For Belgium:
Laboulbenia aubryi
on
Amara aranea
(Coleoptera, Carabidae) and
Rhachomyces spinosus
on
Syntomus foveatus
(Coleoptera, Carabidae). For the Netherlands:
Chitonomyces melanurus
on
Laccophilus minutus
(Coleoptera, Dytiscidae),
Euphoriomyces agathidii
on
Agathidium laevigatum
(Coleoptera, Leiodidae),
Laboulbenia fasciculata
on
Omophron limbatum
(Coleoptera, Carabidae),
Laboulbenia metableti
on
Syntomus foveatus
and
S. truncatellus
(Coleoptera, Carabidae),
Laboulbenia pseudomasei
on
Pterostichus melanarius
(Coleoptera, Carabidae),
Rhachomyces canariensis
on
Trechus obtusus
(Coleoptera, Carabidae), and
Stigmatomyces hydrelliae
on
Hydrellia albilabris
(Diptera, Ephydridae). Finally, an identification key to 140 species of thallus-forming Laboulbeniomycetes in Belgium and the Netherlands is provided. Based on the combined data, we are able to identify mutual gaps that need to be filled as well as weigh the impact of chosen strategies (fieldwork, museum collections) and techniques in these neighboring countries. The aim of this work is to serve as a reference for studying Laboulbeniomycetes fungi in Europe.
This paper, based on a recent comprehensive sampling of insects, is the first report of Laboulbeniales from the New England region since the 1930s. We present 7 new records of laboulbenialean ...parasites on Staphylinidae (rove beetles) and Coccinellidae (lady beetles) from the Boston Harbor Islands National Recreation Area. These are Clonophoromyces nipponicus Terada & I.I. Tav., Hesperomyces virescens Thaxt., Ilyomyces cf. mairei F. Picard, Laboulbenia philonthi Thaxt., Peyritschiella protea Thaxt., Stichomyces conosomatis Thaxt., and Teratomyces actobii Thaxt. One of these parasite species, C. nipponicus, has not been found previously outside of its type locality in Japan. Examination of Roland Thaxter's 1891–1932 slides led to the designation of lectotypes for L. philonthi, P. protea, S. conosomatis, and T. actobii. The following synonymy is established: Teratomyces brevicaulis Thaxt. = T. actobii. In addition, we discovered new localities for H. virescens (from Canada, Cuba, Guatemala, and Japan) and L. philonthi (from Canada, Grenada, Panama, Trinidad, and Venezuela).
Laboulbeniales
(
Ascomycota
) are an order of understudied, biotrophic microfungi uniquely associated with arthropods. More than 2300 species are described but only a fraction of those have been ...sequenced. Molecular studies have shown that cryptic diversity and phenotypic plasticity are present within the
Laboulbeniales
. Thus far, all of the 146 genera described in
Laboulbeniales
have been based on morphological characteristics; features commonly used to delineate genera are the organization of receptacle cells and the number of perithecial outer wall cells. The genus
Botryandromyces
was erected to accommodate two species,
B. heteroceri
and
B. ornatus
(type), which share similar morphological characteristics and are different from other genera in their number of perithecial outer wall cells. Here, we generated sequences of multiple loci (18S, ITS, and 28S) of
B. heteroceri
and several
Laboulbenia
species. Our phylogenetic analyses retrieved
Botryandromyces
within
Laboulbenia
with high support. The two
Botryandromyces
species are similar to related
Laboulbenia
species in their upper receptacle (i.e., cells IV and V). We propose to transfer
Botryandromyces ornatus
and
B. heteroceri
to
Laboulbenia
as
L. heteroceri
and
L. mairei
nom. nov., respectively, due to a complicated taxonomic history. These results advocate the use of molecular data and the necessity of an integrative taxonomy approach in the study of
Laboulbeniales
not only to delineate species, but also to investigate relationships among species, genera, and higher taxa as well as to understand the evolution of morphology in this group of fungi.
Ectomycorrhizal fungi constitute an important component of forest ecosystems that enhances plant nutrition and resistance against stresses. Diversity of ectomycorrhizal (EcM) fungi is, however, ...affected by host plant diversity and soil heterogeneity. This study provides information about the influence of host plants and soil resources on the diversity of ectomycorrhizal fungal fruiting bodies from rainforests of the Democratic Republic of the Congo. Based on the presence of fungal fruiting bodies, significant differences in the number of ectomycorrhizal fungi species existed between forest stand types (p < 0.001). The most ectomycorrhizal species‐rich forest was the Gilbertiodendron dewevrei‐dominated forest (61 species). Of all 93 species of ectomycorrhizal fungi, 19 demonstrated a significant indicator value for particular forest stand types. Of all analysed edaphic factors, the percentage of silt particles was the most important parameter influencing EcM fungi host plant tree distribution. Both host trees and edaphic factors strongly affected the distribution and diversity of EcM fungi. EcM fungi may have developed differently their ability to successfully colonise root systems in relation to the availability of nutrients.
Résumé
Dans les forêts, les champignons ectomycorrhiziens sont impliqués dans la nutrition et la protection des plantes hôtes contre les pathogènes. Leur diversité est influencée par la composition floristique et les facteurs édaphiques. Cette étude traite de l’influence des plantes hôtes et des facteurs édaphiques sur la diversité des sporophores des champignons ectomycorrhiziens dans les forêts denses de la République Démocratique du Congo. Se basant sur la présence de leurs sporophores, on note l’existence des différences significatives entre le nombre d’espèces de champignons ectomycorrhiziens dans les différents types des forêts (P<0.001). La forêt à Gilbertiodendron dewevrei se révèle la plus riche en espèces (61 espèces). Sur un total de 93 espèces de champignons ectomycorrhiziens, 19 sont inféodées aux types particuliers de forêts. La teneur en particules limoneuses est le paramètre édaphique ayant plus d’influence sur la distribution des arbres hôtes des champignons. Le développement de la forêt à Brachystegia laurentii et les espèces des champignons ectomycorrhiziens associées étaient principalement influencé par la teneur en phosphore, alors que le développement des forêts dominées par Gilbertiodendron dewevrei, Uapaca guineensis et Julbernardia seretii était influencé par la teneur en particules sablonneuses. L’acidité aluminique, la teneur en particules limoneuses ainsi que la teneur en particules argileuses sont les paramètres ayant plus d’influence sur la présence des sporophores des champignons ectomycorrhiziens associés à Uapaca heudelotii. Les champignons ectomycorrhiziens ont probablement développé des aptitudes particulières lesquelles leur ont permis de coloniser les systèmes racinaires, en relation avec les ressources minérales disponibles.
Laboulbeniomycetes is a class of fungi that have obligate associations with arthropod hosts, either for dispersal (order Pyxidiophorales) or as biotrophic parasites (orders Herpomycetales and ...Laboulbeniales). Here, we focus on Herpomycetales and Laboulbeniales, which include fungi that form thalli, 3-dimensional, multicellular units of 1000 s of cells. Based on recently published data regarding patterns of speciation, we present the One-Host-One-Parasite model (1H1P) for haustorial thallus-forming Laboulbeniomycetes. We hypothesize that taxa with haustoria, rhizoidal structures that make contact with the host's body cavity, have very strict host specificity. For taxa without haustoria, the microhabitat-as selected by the host-governs host shifting, presence or absence of the fungus, abundance, effective host range, and geographic distribution. We make suggestions for future research including fluorescent labeling of waxy lipids and mass spectrometry. These techniques have the potential to generate the data necessary to evaluate the here proposed 1H1P hypothesis for Herpomycetales and Laboulbeniales.
Laboulbenia littoralis is described from the halobiont Cafius xantholoma (Coleoptera, Staphylinidae); it previously was misidentified and not properly documented. Morphologically the new species ...belongs to a group of carabidicolous taxa similar to Laboulbenia pedicellata and especially Laboulbenia slackensis. It is generally accepted that the specificity of Laboulbeniales is based on their need for substances from the host. In this relatively strict context, shifts between unrelated hosts are difficult to explain. We present morphological and ecological evidence supporting the hypothesis that these fungi are capable of shifting between unrelated hosts as long as they share the same habitat. Adaptation to a particular environment, combined with a reduced dependence from specific nutrients of the host, explains the proposed interfamilial host shift.
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