385 research outputs found
Description and DNA barcoding of three new species of Leohumicola from South Africa and the United States
Three new species of Leohumicola (anamorphic Leotiomycetes) are described using morphological characters and phylogenetic analyses of DNA barcodes. Leohumicola levissima and L. atra were isolated from soils collected after forest fires in Crater Lake National Park, United States. Leohumicola incrustata was isolated from burned fynbos from the Cape of Good Hope Nature Reserve, South Africa. The three species exhibit characteristic Leohumicola morphology but are morphologically distinct based on conidial characters. Two DNA barcode regions, the Internal Transcribed Spacer (ITS) nuclear rDNA region and the cytochrome oxidase subunit I (Cox1) mitochondrial gene, were sequenced. Single-gene parsimony, dual-gene parsimony and dual-gene Bayesian inference phylogenetic analyses support L. levissima, L. atra, L. incrustata as distinct phylogenetic species. Both ITS and Cox1 barcodes are effective for the molecular identification of Leohumicola species
Ochratoxin production and taxonomy of the yellow aspergilli (Aspergillus section Circumdati)
AbstractAspergillus section Circumdati or the Aspergillus ochraceus group, includes species with rough walled stipes, biseriate conidial heads, yellow to ochre conidia and sclerotia that do not turn black. Several species are able to produce mycotoxins including ochratoxins, penicillic acids, and xanthomegnins. Some species also produce drug lead candidates such as the notoamides. A polyphasic approach was applied using morphological characters, extrolite data and partial calmodulin, β-tubulin and ITS sequences to examine the evolutionary relationships within this section. Based on this approach the section Circumdati is revised and 27 species are accepted, introducing seven new species: A. occultus, A. pallidofulvus, A. pulvericola, A. salwaensis, A. sesamicola, A. subramanianii and A. westlandensis. In addition we correctly apply the name A. fresenii (≡ A. sulphureus (nom. illeg.)). A guide for the identification of these 27 species is provided. These new species can be distinguished from others based on morphological characters, sequence data and extrolite profiles. The previously described A. onikii and A. petrakii were found to be conspecific with A. ochraceus, whilst A. flocculosus is tentatively synonymised with A. ochraceopetaliformis, despite extrolite differences between the two species. Based on the extrolite data, 13 species of section Circumdati produce large amounts of ochratoxin A: A. affinis, A. cretensis, A. fresenii, A. muricatus, A. occultus, A. ochraceopetaliformis (A. flocculosus), A. ochraceus, A. pseudoelegans, A. pulvericola, A. roseoglobulosus, A. sclerotiorum, A. steynii and A. westerdijkiae. Seven additional species produce ochratoxin A inconsistently and/or in trace amounts: A. melleus, A. ostianus, A. persii, A. salwaensis, A. sesamicola, A. subramanianii and A. westlandensis. The most important species regarding potential ochratoxin A contamination in agricultural products are A. ochraceus, A. steynii and A. westerdijkiae
Identification and nomenclature of the genus Penicillium
AbstractPenicillium is a diverse genus occurring worldwide and its species play important roles as decomposers of organic materials and cause destructive rots in the food industry where they produce a wide range of mycotoxins. Other species are considered enzyme factories or are common indoor air allergens. Although DNA sequences are essential for robust identification of Penicillium species, there is currently no comprehensive, verified reference database for the genus. To coincide with the move to one fungus one name in the International Code of Nomenclature for algae, fungi and plants, the generic concept of Penicillium was re-defined to accommodate species from other genera, such as Chromocleista, Eladia, Eupenicillium, Torulomyces and Thysanophora, which together comprise a large monophyletic clade. As a result of this, and the many new species described in recent years, it was necessary to update the list of accepted species in Penicillium. The genus currently contains 354 accepted species, including new combinations for Aspergillus crystallinus, A. malodoratus and A. paradoxus, which belong to Penicillium section Paradoxa. To add to the taxonomic value of the list, we also provide information on each accepted species MycoBank number, living ex-type strains and provide GenBank accession numbers to ITS, β-tubulin, calmodulin and RPB2 sequences, thereby supplying a verified set of sequences for each species of the genus. In addition to the nomenclatural list, we recommend a standard working method for species descriptions and identifications to be adopted by laboratories working on this genus
A taxonomic and phylogenetic revision of Penicillium section Aspergilloides
AbstractSpecies belonging to Penicillium section Aspergilloides have a world-wide distribution with P. glabrum, P. spinulosum and P. thomii the most well-known species of this section. These species occur commonly and can be isolated from many substrates including soil, food, bark and indoor environments. The taxonomy of these species has been investigated several times using various techniques, but species delimitation remains difficult. In the present study, 349 strains belonging to section Aspergilloides were subjected to multilocus molecular phylogenetic analyses using partial β-tubulin (BenA), calmodulin (CaM) and RNA polymerase II second largest subunit (RPB2) sequences. Section Aspergilloides is subdivided into 12 clades and 51 species. Twenty-five species are described here as new and P. yezoense, a species originally described without a Latin diagnosis, is validated. Species belonging to section Aspergilloides are phenotypically similar and most have monoverticillate conidiophores and grow moderately or quickly on agar media. The most important characters to distinguish these species were colony sizes on agar media, growth at 30 °C, ornamentation and shape of conidia, sclerotium production and stipe roughness
A taxonomic and phylogenetic revision of the Penicillium sclerotiorum complex
The morphological concept of Penicillium sclerotiorum (subgenus Aspergilloides) includes strains with monoverticillate, vesiculate conidiophores, and vivid orange to red colony colours, with colourful sclerotia sometimes produced. Multigene phylogenetic analyses with the nuclear ribosomal internal transcribed spacer (ITS) region, cytochrome c oxidase subunit 1 (cox1), β-tubulin (benA), translation elongation factor 1-α (tef1-α), and calmodulin (cmd), reveal that the P. sclerotiorum morphospecies is a complex of seven phylogenetically distinct species, three of which were recently described, namely P. guanacastense, P. mallochii, and P. viticola. Three previously unidentified species are described here as P. cainii, P. jacksonii, and P. johnkrugii. The phylogenetic species are morphologically similar, but differ in combinations of colony characters, sclerotium production, conidiophore stipe roughening and branching, and conidial shape. Ecological characters and differences in geographical distribution further characterise some of the species, but increased sampling is necessary to confirm these differences. The fungal DNA barcode, the ITS, and the animal DNA barcode, cox1, have lower species resolving ability in our phylogenetic analyses, but still allow identification of all the species. Tef1-α and cmd were superior in providing fully resolved, statistically well-supported phylogenetic trees for this species complex, whereas benA resolved all species but had some issues with paraphyly. Penicillium adametzioides and P. multicolor, considered synonyms of P. sclerotiorum by some previous authors, do not belong to the P. sclerotiorum complex
Phylogeny, identification and nomenclature of the genus Aspergillus
AbstractAspergillus comprises a diverse group of species based on morphological, physiological and phylogenetic characters, which significantly impact biotechnology, food production, indoor environments and human health. Aspergillus was traditionally associated with nine teleomorph genera, but phylogenetic data suggest that together with genera such as Polypaecilum, Phialosimplex, Dichotomomyces and Cristaspora, Aspergillus forms a monophyletic clade closely related to Penicillium. Changes in the International Code of Nomenclature for algae, fungi and plants resulted in the move to one name per species, meaning that a decision had to be made whether to keep Aspergillus as one big genus or to split it into several smaller genera. The International Commission of Penicillium and Aspergillus decided to keep Aspergillus instead of using smaller genera. In this paper, we present the arguments for this decision. We introduce new combinations for accepted species presently lacking an Aspergillus name and provide an updated accepted species list for the genus, now containing 339 species. To add to the scientific value of the list, we include information about living ex-type culture collection numbers and GenBank accession numbers for available representative ITS, calmodulin, β-tubulin and RPB2 sequences. In addition, we recommend a standard working technique for Aspergillus and propose calmodulin as a secondary identification marker
Discovery of the teleomorph of the hyphomycete, Sterigmatobotrys macrocarpa, and epitypification of the genus to holomorphic status
Sterigmatobotrys macrocarpa is a conspicuous, lignicolous,
dematiaceous hyphomycete with macronematous, penicillate conidiophores with
branches or metulae arising from the apex of the stipe, terminating with
cylindrical, elongated conidiogenous cells producing conidia in a holoblastic
manner. The discovery of its teleomorph is documented here based on
perithecial ascomata associated with fertile conidiophores of S.
macrocarpa on a specimen collected in the Czech Republic; an identical
anamorph developed from ascospores isolated in axenic culture. The teleomorph
is morphologically similar to species of the genera Carpoligna and
Chaetosphaeria, especially in its nonstromatic perithecia, hyaline,
cylindrical to fusiform ascospores, unitunicate asci with a distinct apical
annulus, and tapering paraphyses. Identical perithecia were later observed on
a herbarium specimen of S. macrocarpa originating in New Zealand.
Sterigmatobotrys includes two species, S. macrocarpa, a
taxonomic synonym of the type species, S. elata, and S.
uniseptata. Because no teleomorph was described in the protologue of
Sterigmatobotrys, we apply Article 59.7 of the International Code of
Botanical Nomenclature. We epitypify (teleotypify) both Sterigmatobotrys
elata and S. macrocarpa to give the genus holomorphic status,
and the name S. macrocarpa is adopted for the holomorph. To evaluate
the ordinal and familial affinities of Sterigmatobotrys and its
relationships with the morphologically similar genera Carpoligna and
Chaetosphaeria, phylogenetic relationships were inferred based on
aligned sequences of the large subunit nuclear ribosomal DNA (ncLSU rDNA)
An overview of the taxonomy, phylogeny, and typification of nectriaceous fungi in Cosmospora, Acremonium, Fusarium, Stilbella, and Volutella
A comprehensive phylogenetic reassessment of the ascomycete genus
Cosmospora (Hypocreales, Nectriaceae) is undertaken using
fresh isolates and historical strains, sequences of two protein encoding
genes, the second largest subunit of RNA polymerase II (rpb2), and a
new phylogenetic marker, the larger subunit of ATP citrate lyase
(acl1). The result is an extensive revision of taxonomic concepts,
typification, and nomenclatural details of many anamorph- and
teleomorph-typified genera of the Nectriaceae, most notably
Cosmospora and Fusarium. The combined phylogenetic analysis
shows that the present concept of Fusarium is not monophyletic and
that the genus divides into two large groups, one basal in the family, the
other terminal, separated by a large group of species classified in genera
such as Calonectria, Neonectria, and Volutella. All accepted
genera received high statistical support in the phylogenetic analyses.
Preliminary polythetic morphological descriptions are presented for each
genus, providing details of perithecia, micro- and/or macro-conidial
synanamorphs, cultural characters, and ecological traits. Eight species are
included in our restricted concept of Cosmospora, two of which have
previously documented teleomorphs and all of which have
Acremonium-like microconidial anamorphs. A key is provided to the
three anamorphic species recognised in Atractium, which is removed
from synonymy with Fusarium and epitypified for two macroconidial
synnematous species and one sporodochial species associated with waterlogged
wood. Dialonectria is recognised as distinct from Cosmospora
and two species with teleomorph, macroconidia and microconidia are accepted,
including the new species D. ullevolea. Seven species, one with a
known teleomorph, are classified in Fusicolla, formerly considered a
synonym of Fusarium including members of the F. aquaeductuum
and F. merismoides species complex, with several former varieties
raised to species rank. Originally a section of Nectria,
Macroconia is raised to generic rank for five species, all producing
a teleomorph and macroconidial anamorph. A new species of the
Verticillium-like anamorphic genus Mariannaea is described
as M. samuelsii. Microcera is recognised as distinct from
Fusarium and a key is included for four macroconidial species, that
are usually parasites of scale insects, two of them with teleomorphs. The four
accepted species of Stylonectria each produce a teleomorph and micro-
and macroconidial synanamorphs. The Volutella species sampled fall
into three clades. Pseudonectria is accepted for a perithecial and
sporodochial species that occurs on Buxus. Volutella s. str.
also includes perithecial and/or sporodochial species and is revised to
include a synnematous species formerly included in Stilbella. The
third Volutella-like clade remains unnamed. All fungi in this paper
are named using a single name system that gives priority to the oldest generic
names and species epithets, irrespective of whether they are originally based
on anamorph or teleomorph structures. The rationale behind this is
discussed
Taxonomy, nomenclature and phylogeny of three cladosporium-like hyphomycetes, Sorocybe resinae, Seifertia azaleae and the Hormoconis anamorph of Amorphotheca resinae
Using morphological characters, cultural characters, large subunit and
internal transcribed spacer rDNA (ITS) sequences, and provisions of the
International Code of Botanical Nomenclature, this paper attempts to resolve
the taxonomic and nomenclatural confusion surrounding three species of
cladosporium-like hyphomycetes. The type specimen of Hormodendrum
resinae, the basis for the use of the epithet resinae for the
creosote fungus {either as Hormoconis resinae or Cladosporium
resinae) represents the mononematous synanamorph of the synnematous,
resinicolous fungus Sorocybe resinae. The phylogenetic relationships
of the creosote fungus, which is the anamorph of Amorphotheca
resinae, are with the family Myxotrichaceae, whereas S.
resinae is related to Capronia (Chaetothyriales,
Herpotrichiellaceae). Our data support the segregation of
Pycnostysanus azaleae, the cause of bud blast of rhododendrons, in
the recently described anamorph genus Seifertia, distinct from
Sorocybe; this species is related to the Dothideomycetes but
its exact phylogenetic placement is uncertain. To formally stabilize the name
of the anamorph of the creosote fungus, conservation of Hormodendrum
resinae with a new holotype should be considered. The paraphyly of the
family Myxotrichaceae with the Amorphothecaceae suggested by
ITS sequences should be confirmed with additional genes
A without-prejudice list of generic names of fungi for protection under the International Code of Nomenclature for algae, fungi, and plants
As a first step towards the production of a List of Protected Generic Names for Fungi, a without-prejudice list is presented here as a basis for future discussion and the production of a List for formal adoption. We include 6995 generic names out of the 17072 validly published names proposed for fungi and invite comments from all interested mycologists by 31 March 2014. The selection of names for inclusion takes note of recent major publications on different groups of fungi, and further the decisions reached so far by international working groups concerned with particular families or genera. Changes will be sought in the Code to provide for this and lists at other ranks to be protected against any competing unlisted names, and to permit the inclusion of names of lichen-forming fungi. A revised draft will be made available for further discussion at the 10th International Mycological Congress in Bangkok in August 2014. A schedule is suggested for the steps needed to produce a list for adoption by the International Botanical Congress in August 2017. This initiative provides mycologists with an opportunity to place nomenclature at the generic level on a more secure and stable base
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