Aspergillus series Versicolores members occur in a wide range of environments and substrates such as indoor environments, food, clinical materials, soil, caves, marine or hypersaline ecosystems. The taxonomy of the series has undergone numerous re-arrangements including a drastic reduction in the number of species and subsequent recovery to 17 species in the last decade. The identification to species level is however problematic or impossible in some isolates even using DNA sequencing or MALDI-TOF mass spectrometry indicating a problem in the definition of species boundaries. To revise the species limits, we assembled a large dataset of 518 strains. From these, a total of 213 strains were selected for the final analysis according to their calmodulin (CaM) genotype, substrate and geography. This set was used for phylogenetic analysis based on five loci (benA, CaM, RPB2, Mcm7, Tsr1). Apart from the classical phylogenetic methods, we used multispecies coalescence (MSC) model-based methods, including one multilocus method (STACEY) and five single-locus methods (GMYC, bGMYC, PTP, bPTP, ABGD). Almost all species delimitation methods suggested a broad species concept with only four species consistently supported. We also demonstrated that the currently applied concept of species is not sustainable as there are incongruences between single-gene phylogenies resulting in different species identifications when using different gene regions. Morphological and physiological data showed overall lack of good, taxonomically informative characters, which could be used for identification of such a large number of existing species. The characters expressed either low variability across species or significant intraspecific variability exceeding interspecific variability. Based on the above-mentioned results, we reduce series Versicolores to four species, namely A. versicolor, A. creber, A. sydowii and A. subversicolor, and the remaining species are synonymized with either A. versicolor or A. creber. The revised descriptions of the four accepted species are provided. They can all be identified by any of the five genes used in this study. Despite the large reduction in species number, identification based on phenotypic characters remains challenging, because the variation in phenotypic characters is high and overlapping among species, especially between A. versicolor and A. creber. Similar to the 17 narrowly defined species, the four broadly defined species do not have a specific ecology and are distributed worldwide. We expect that the application of comparable methodology with extensive sampling could lead to a similar reduction in the number of cryptic species in other extensively studied Aspergillus species complexes and other fungal genera. Citation: Sklenář F, Glässnerová K, Jurjević Ž, Houbraken J, Samson RA, Visagie CM, Yilmaz N, Gené J, Cano J, Chen AJ, Nováková A, Yaguchi T, Kolařík M, Hubka V (2022). Taxonomy of Aspergillus series Versicolores: species reduction and lessons learned about intraspecific variability. Studies in Mycology 102 : 53-93. doi: 10.3114/sim.2022.102.02.

In the course of taxonomic studies on saprobic microfungi from Spain, several slow-growing, dematiaceous hyphomycetes were isolated from soil, submerged plant material and river sediments. Sixteen of these strains were identified as members of the ascomycete order Chaetothyriales on the basis of morphology and DNA sequence analyses of the internal transcribed spacer region and partial large subunit ribosomal RNA gene. These included three novel species ( Cladophialophora pseudocarrionii , Cyphellophora chlamydospora , and Rhinocladiella amoena ) and five interesting, little-known or clinically-relevant species ( Cyphellophora suttonii , Exophiala aquamarina , E. lacus , E. radicis , and Rhinocladiella similis ) . In addition, Exophiala oligosperma , an emerging opportunistic fungus, was found for the first time in an aquatic freshwater environment (river sediments). Cladophialophora pseudocarrionii resembles C. carrionii in the branching pattern of its conidial chains, but differs from the latter species in its inability to grow at 30 °C. Cyphellophora chlamydospora differs from other species of the genus in the absence of conidiation, producing only chlamydospores in vitro. Rhinocladiella amoena shows branched conidiophores similar to those of R. anceps , R. atrovirens , R. basitona and R. similis , but differs from them in conidial shape and size. The ex-type strain of Phialophora livistonae , included in the phylogenetic study, clustered with high statistical support with members of the genus Cyphellophora and is transferred to this genus.

The circumscription of the genus Acremonium (Hypocreales) was recently reviewed on the basis of a DNA phylogenetic study. Several species were subsequently transferred to Sarocladium, but the relationships between both genera remained unresolved. Based on multilocus phylogenetic inferences combined with phenotypic data, we have revised the species concepts within Sarocladium and some genetically related species of Acremonium. As a result of these studies, six species are described as new, viz. S. bifurcatum, S. gamsii, S. hominis, S. pseudostrictum, S. subulatum and S. summerbellii. In addition, the new combinations S. implicatum and S. terricola are proposed for A. implicatum and A. terricola, respectively. Sarocladium attenuatum is confirmed as synonym of the type species of the genus, S. oryzae. An epitype and neotype are also introduced for S. oryzae and S. implicatum, respectively. Although Sarocladium species have traditionally been considered as important phytopathogens, the genus also contains opportunistic human pathogens. This study extends the spectrum of clinical species that could be diagnosed as causal agents of human infections.

The fungal genus Curvularia includes numerous plant pathogens and some emerging opportunistic pathogens of humans. In a previous study we used morphology and sequences of the nuclear ribosomal internal transcribed spacer region (ITS) and the glyceraldehyde-3-phosphate dehydrogenase (gpd) gene to identify species within a set of 99 clinical Curvularia isolates from the USA. Seventy-two isolates could be identified while the remaining 27 isolates belonged in three unclassified clades that were tentatively labelled Curvularia sp. I, II and III. In the present study, we further assess the taxonomic placement of these isolates using sequences of ITS, gpd, the large subunit rDNA, and the second largest subunit of RNA polymerase II. DNA sequence comparisons with a set of 87 isolates representing 33 Curvularia spp. and members of the closely-related genera Bipolaris and Exserohilum revealed that Curvularia sp. I, II and III represent novel lineages in Curvularia. These lineages are morphologically different from the currently accepted species. In the phylogenetic tree, Curvularia sp. I and sp. III were each split into two distinct lineages. Morphology and phylogeny supported the proposal of five new species, to be named C. americana, C. chlamydospora, C. hominis, C. muehlenbeckiae and C. pseudolunata. The concatenated 4-locus phylogeny revealed the existence of six clades in Curvularia, which are associated with particular morphological features. They were named after representative species, namely americana, eragrostidis, hominis, lunata, spicifera and trifolii.

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Numerous members of Ascomycota and Basidiomycota produce only poorly differentiated arthroconidial asexual morphs in culture. These arthroconidial fungi are grouped in genera where the asexual-sexual connections and their taxonomic circumscription are poorly known. In the present study we explored the phylogenetic relationships of two of these ascomycetous genera, Arthrographis and Arthropsis. Analysis of D1/D2 sequences of all species of both genera revealed that both are polyphyletic, with species being accommodated in different orders and classes. Because genetic variability was detected among reference strains and fresh isolates resembling the genus Arthrographis, we carried out a detailed phenotypic and phylogenetic analysis based on sequence data of the ITS region, actin and chitin synthase genes. Based on these results, four new species are recognised, namely Arthrographis chlamydospora, A. curvata, A. globosa and A. longispora. Arthrographis chlamydospora is distinguished by its cerebriform colonies, branched conidiophores, cuboid arthroconidia and terminal or intercalary globose to subglobose chlamydospores. Arthrographis curvata produced both sexual and asexual morphs, and is characterised by navicular ascospores and dimorphic conidia, namely cylindrical arthroconidia and curved, cashewnut-shaped conidia formed laterally on vegetative hyphae. Arthrographis globosa produced membranous colonies, but is mainly characterised by doliiform to globose arthroconidia. Arthrographis longispora also produces membranous colonies, but has poorly differentiated conidiophores and long arthroconidia. Morphological variants are described for A. kalrae and our results also revealed that Eremomyces langeronii and A. kalrae, traditionally considered the sexual and asexual morphs of the same species, are not conspecific.

A set of 104 isolates from human clinical samples from the United States, morphologically compatible with Bipolaris, were morphologically and molecularly identified through the sequence analysis of the internal transcribed space (ITS) region of the nuclear ribosomal DNA (rDNA). The predominant species was Bipolaris spicifera (67.3%), followed by B. hawaiiensis (18.2%), B. cynodontis (8.6%), B. micropus (2.9%), B. australiensis (2%), and B. setariae (1%). Bipolaris cynodontis, B. micropus, and B. setariae represent new records from clinical samples. The most common anatomical sites where isolates were recovered were the nasal region (30.7%), skin (19.2%), lungs (14.4%), and eyes (12.5%). The antifungal susceptibilities of 5 species of Bipolaris to 9 drugs are provided. With the exception of fluconazole and flucytosine, the antifungals tested showed good activity.

ABSTRACT Several members of the fungal genera Phialemonium and Lecythophora are occasional agents of severe human and animal infections. These species are difficult to identify, and relatively little is known about their frequency in the clinical setting. The objective of this study was to characterize morphologically and molecularly, on the basis of the analysis of large-subunit ribosomal DNA sequences, a set of 68 clinical isolates presumed to belong to these genera. A total of 59 isolates were determined to be Phialemonium species (n = 32) or a related Cephalotheca species (n = 6) or Lecythophora species (n = 20) or a related Coniochaeta species (n = 1). Nine isolates identified to be Acremonium spp. or Phaeoacremonium spp. were excluded from further study. The most common species were Phialemonium obovatum and Phialemonium curvatum, followed by Lecythophora hoffmannii, Cephalotheca foveolata, and Lecythophora mutabilis.

Some species in the polyphyletic fungal genus Acremonium are important opportunist pathogens. Determining the actual spectrum of species and their incidence in the clinical setting, however, has long been hampered because of the difficulties encountered in phenotypic species-level identification. The goal of this study was to re-identify a large number of clinical isolates morphologically and to confirm the identifications by comparing sequences of the internal transcribed spacer region of the rRNA gene of these isolates to those of type or reference strains of well-known Acremonium species. Of the 119 isolates referred to a United States reference laboratory under the name Acremonium, only 75 were identified morphologically as belonging to that genus. The remainder (44 isolates) were identified as belonging to other morphologically similar genera. The Acremonium clinical isolates were related to species of Hypocreales, Sordariales, and of an incertae sedis family of ascomycetes, Plectosphaerellaceae. A total of 50 of the 75 Acremonium isolates (67%) could be identified by molecular means, the prevalent species being Acremonium kiliense (15 isolates), A. sclerotigenum-A. egyptiacum (11 isolates), A. implicatum (7 isolates), A. persicinum (7 isolates), and A. atrogriseum (4 isolates). One of the most interesting findings of our study was that we identified several species among this large collection of clinical isolates that had not previously been reported from human infections, and we failed to confirm other Acremonium species, such as A. potronii, A. recifei, and A. strictum, that had been considered significant. The most common anatomic sites for Acremonium isolates were the respiratory tract (41.3%), nails (10.7%), and the eye (9.3%). Antifungal susceptibility testing demonstrated high MICs for all agents tested, except for terbinafine. Since numerous isolates could not be identified, we concluded that the list of opportunistic Acremonium species is far from be complete and that a considerable number of additional species will be discovered.

Research on orphan diseases has been boosted enormously over the last decade with the event of electronic communication. This has enabled the implementation of international networks providing research groups with sufficient critical mass for epidemiological studies. An example of such a success story is without doubt the knowledge on Scedosporium and its teleomorph Pseudallescheria. Although already known from human infections since the late 19th century, these fungi had long been regarded either as clinically insignificant, or as anecdotal. Today the species are listed among the major groups of filamentous opportunists.1,2 First attempts to unite researchers and clinicians were made by the Spanish Study Group on Scedosporium prolificans. In 2002, a Europe-wide group was founded under the umbrella of the European Confederation of Medical Mycology (ECMM). As similar initiatives were undertaken in Australia by the Australian Scedosporium Study Group (AUSCEDO), the two groups were internationalized under the auspices of the International Society of Human and Animal Mycology (ISHAM). Main objective of the Working Group Pseudallescheria/Scedosporium Infections was to gain insight into the epidemiology and genetic variability of these fungi and to provide data on possible sources of contamination and routes of infection. The taxonomy of the fungi had been revolutionised by the application of molecular methods, particularly through the papers of Gilgado et al.[3–5] The classical species Pseudallescheria boydii was subdivided into numerous species, several of which were indistinguishable by phenotypic characteristics that had been in use until recently. A complicating factor is the different degree of inbreeding and clonality between species, leaving doubt whether all genealogically separated entities can be referred to as species in the classical sense.6 In addition, it remains questionable whether distinction of all entities is clinically meaningful. But at least there is a wide consensus that Pseudallescheria is a species complex rather than a single species. Species have limited molecular heterogeneity and comprise limited numbers of haplotypes. A number of molecular techniques for diagnostics and detection are currently being developed using genes that have been suitable for identification of species. The widely used rDNA internal transcribed spacer (ITS) region of rDNA is suitable for the majority of clearly distinct taxa,7,8 whereas molecular siblings are separable by different loci in the β-tubulin gene.3,4 Scedosporium species are opportunists and thus understanding of their behaviour in human tissue can be reached only via knowledge of their environmental habitat. Kaltseis et al. [9] noted that Scedosporium species are positively associated with human-derived, industrial and agricultural pollution. Comparing the frequency of species from the environment with the distribution of species involved in human infection, the authors supposed significant difference in virulence between species. Virulence is concentrated in two locations in the phylogeny of Microascales with Scedosporium-like appearance, viz. in the Pseudallescheria boydii complex discussed above, and in Scedosporium prolificans.10 These fungi primarily cause subcutaneous infections in healthy individuals, or deep, occasionally disseminated infections in debilitated patients. A remarkable, newly recognised clinical syndrome is the near-drowning encephalitis, a delayed infection of the brain after aspiration of polluted water resulting in temporary coma.11,12 With improved isolation and detection techniques13–16Scedosporium species have also become recognised as common colonisers of the airways of patients with cystic fibrosis.17 The direct clinical significance of this finding is still unclear,18 but infection may be regarded as a contraindication for lung transplantation,19,20 the ultimate therapy for CF patients. Scedosporium infections are notoriously difficult to treat due to their limited susceptibility to most commonly used systemic antifungals. Species share this property with the Scopulariopsis agents of cutaneous infections, which belong to the same order, Microascales. In the filamentous ascomycetes such recalcitrance to therapy is matched only by the order Hypocreales, containing the genera Acremonium, Fusarium and Trichoderma. Scedosporium prolificans belongs to the fungi with the highest degree of resistance to antifungals known. Reasonable results have been obtained with combination therapy using voriconazole and terbinafin,21,22 but in general mortality rates in disseminated infections by this fungus rise until up to 87.5%.23 Infections caused by species of the P. boydii complex have proved less difficult to treat, with voriconazole being the drug of choice.24,25 Strains are currently identifiable with the sequence base available at http://www.scedosporium-ecmm.com. Species concepts applied in this database have been verified by multilocus analysis including several gene loci (ITS, BT2, TUB) and AFLP profiles, and taxonomy has been anchored by the inclusion of type strains. The database is divided up between clinical and environmental strains (Fig. 1) because metadata for the two categories are very different, but the identification procedure is identical. ITS and the BT2 and TUB loci of β-tubulin are sufficient for reliable identification. At the University of Sydney Westmead Hospital, a database for multilocus sequence typing applying six genetic loci for Scedosporium aurantiacum was developed and is accessible at http://mlst.mycologylab.org (A. Harun & W. Meyer, unpublished data). Clinical data are automatically transmitted to the Fungiscope database, where tools for epidemiological analysis are being installed. Deposition of live material is recommended in one of the recognised culture collections joining the project (Fig. 1), whereby the Belgian Coordinated Collection of Microorganisms at the Scientific Institute of Public Health (Brussels) serves as a prime depository for environmental strains. Strains are available to members of the Working Group if permission from the depositor is granted. A taxonomic database is available through MycoBank (http://www.mycobank.org), while a nearly complete collection of clinical papers published before 2006 is available on the ISHAM website (http://www.isham.org). Note that there is no link to GenBank, as this database is not updated according to taxonomic developments and sequences are not verified with ex-type materials. Flow diagram of data storage of clinical and environmental strains. The cooperating Working Groups have thus provided a basic infrastructure that is essential for the growth of knowledge on Pseudallescheria and Scedosporium. We offer access to a broad range of information on these emerging fungal opportunists, which should lead to appropriate and effective therapy. Clearly, the success of this endeavour depends on the ongoing activity of its supporters. Readers of this special issue are cordially invited to contribute to the network. The present special issue stems from presentations given at the PSI workshop held in Bonn, Germany, 6−8 May, 2010. The authors have no conflict of interests to declare.

In a study on soil microfungi from different countries two new hyphomycetes were found. The first one, Ramophialophora humicola, isolated from a soil sample collected in Ronda (Spain), is characterized by producing profusely branched conidiophores ending in sterile, sometimes swollen apices, and subhyaline, dacryoid conidia borne from both integrated and discrete phialides with conspicuous collaretes. ITS sequence data reveal its relationships with members of the Sordariales and its genetic differences with other fungi morphologically close, such as Cladorrhinum spp. The second species, Fibulochlamys chilensis, isolated from a soil sample collected in La Junta (Chile), is characterized by micronematous, clamped, mostly branched conidiophores producing thallic, one-celled, thick-walled conidia that exhibit strongly wrinkled surfaces in age. The analysis of partial sequences of the ITS region and 28S rRNA gene reveal that this fungus is close to members of the gilled Agaricales.

Sporothrix inflata is a saprobic member of the Ophiostoma stenoceras-Sporothrix schenckii species complex, reported mainly from soil. Ophiostoma bragantinum, an ascomycete described from Brazil, has been proposed as its possible teleomorph. Previous studies revealed that Sporothrix inflata is phenotypically and genetically variable, suggesting the existence of cryptic species. During a continued survey on the biodiversity of microfungi from different countries, seven isolates morphologically similar to S. inflata were obtained from soil samples collected in Spain and USA. In this study their phenotypic features and phylogenetic relationships were assessed. DNA sequence data of two nuclear loci revealed that these isolates correspond to two unnamed clades in S. inflata s.l., one of which also included the type strain of Humicola dimorphospora, a species that traditionally has been considered a synonym of S. inflata. These two groups are proposed herein as Sporothrix brunneoviolacea sp. nov. and Sporothrix dimorphospora comb. nov. S. brunneoviolacea is characterized phenotypically by the production of a diffusible violet-brown pigment in culture and mostly globose, pigmented, lateral blastoconidia. On the other hand S. dimorphospora lacks diffusible pigments and shows mostly subglobose to obovoid pigmented lateral blastoconidia. In contrast to the type strain of S. inflata S. brunneoviolacea and S. dimorphospora assimilate raffinose. The phylogenetic analysis suggested that the proposed anamorph-teleomorph connection between S. inflata and O. bragantinum might not be correct.

A comparative study on the experimental pathogenicity of five species of Sporothrix of clinical interest, Sporothrix albicans, Sporothrix brasiliensis, Sporothrix globosa, Sporothrix mexicana, and Sporothrix schenckii sensu stricto, was performed using an immunocompetent murine model. Two strains of each species and two levels of inoculum for each strain (2x10(7) and 2x10(4) conidia/animal) were tested by intravenous inoculation of mice (ten per group). Mortality was caused by the low inoculum of one strain of S. brasiliensis only, and the high inocula of S. brasiliensis and S. schenckii strains. Other inocula and other species tested did not kill any of the experimental animals. Tissue burden studies showed fungal spread to kidneys, lungs, spleen, brain, and testicles. S. brasiliensis was recovered extensively from all of the studied organs, and S. schenckii and S. globosa were recovered in lower amounts. Histopathological studies revealed differences in the lesions, which ranged from local inflammation with a low number of fungal cells at the injection site in mice infected with S. globosa, to massive infiltration of fungal cells in organs of those infected with S. brasiliensis. Our findings showed that S. brasiliensis and S. schenckii were the most virulent species, and suggest that lesional mechanisms could be species-specific.

ABSTRACT Several members of the order Mucorales (subphylum Mucoromycotina ) are important agents of severe human infections. The identification of these fungi by using standard mycologic methods is often difficult and time consuming. Frequently, the etiological agent in clinical cases is reported either as a Mucor sp., which is not the most frequent genus of zygomycetes, or only as a member of the Mucorales . For this reason, the actual spectrum of species of zygomycetes and their incidences in the clinical setting is not well known. The goals of this study were to compare the results of the molecular identification of an important set of clinical isolates, received in a mycological reference center from different regions of the United States, with those obtained by using the traditional morphological methods and to determine the spectrum of species involved. We tested 190 isolates morphologically identified as zygomycetes by using sequencing of the internal transcribed spacer (ITS) region of the ribosomal DNA. Molecular identification revealed that Rhizopus oryzae represented approximately half (44.7%) of these isolates. The remainder was identified as Rhizopus microsporus (22.1%), Mucor circinelloides (9.5%), Mycocladus corymbifer (formerly Absidia corymbifera ) (5.3%), Rhizomucor pusillus (3.7%), Cunninghamella bertholletiae (3.2%), Mucor indicus (2.6%), Cunninghamella echinulata (1%), and Apophysomyces elegans (0.5%). The most common anatomic sites for clinically significant zygomycetes, as determined by isolates sent to the Fungus Testing Laboratory for identification and/or susceptibility testing and included in this study, were the sinuses, lungs, and various cutaneous locations, at 25.8%, 26.8%, and 28%, respectively. These sites represented approximately 80% of the isolates evaluated. A high level of correlation (92.6%) between morphological and molecular identifications was found.

In this study we have determined the morphological, some physiological and biochemical characteristics of a fungal strain isolated from balsamic and cider vinegars. The examination of fungal contamination of 100 balsamic and cider vinegar samples showed that 90% contained more than 104 colony forming units (CFU ml−1), but in most samples (65%) values of more than 105 CFU ml−1 were obtained. The most frequent contamination was with Monascus sp. (80% of the samples examined showed 2 × 103 to 6 × 105 CFU ml−1). This mould can produce secondary metabolites such as citrinin and monacolin KL (lactone form), and monacolin KA (acid form). Using high-performance liquid chromatography (HPLC) with fluorescence detection, citrinin was found in 68% of the samples. The concentration of these mycotoxins varied between 1.6 × 10−2 µg ml−1 and 7.2 × 10−2 µg ml−1. The concentrations of citrinin were very low, and we can anticipate that this compound at these concentrations has no toxic effects on renal cells. Monacolin was not detected in any sample studied.

The identification of fungal species and determination of their significance in the clinical laboratory are complex practices that help establish or exclude a fungal cause of disease. In the past, the clinical mycologist utilized a limited array of phenotypic measurements for categorizing isolates to the species level. This scenario is shifting in favor of molecular identification strategies largely due to a combination of several factors: (i) the changing landscape of epidemiology of medically important fungi, in which novel organisms never before implicated in human infection are being reported from clinical samples (10, 41); (ii) reports of species-specific differences in antifungal susceptibilities of these newly recognized fungi (4, 10, 41); (iii) numerous studies demonstrating that morphology alone may not be a sufficiently objective method for species determination (7, 8, 10, 23, 41); and (iv) a growing scarcity of bench scientists and microbiologists trained in traditional mycology. With the increasing incidence of fungal infections and reports of invasive fungal infections in nontraditional populations, such as patients with critical illnesses, the onus is on the clinical microbiologist/mycologist to return a timely and accurate identification. Molecular methods are rapid with a turnaround time of about 24 h from the time of DNA extraction, yield results that are objective with data portable between labs, and could be more economical in the long run. Few topics are more controversial or evoke such a passionate response as the term “species” to a mycologist. Molecular studies have demonstrated that a strategy where multiple genes (or portions thereof) are sequenced and the resultant data are analyzed by phylogenetic methods is a robust strategy for fungal species recognition. This concept, known as phylogenetic species recognition (PSR) (40), has been used successfully to define species in the genera Fusarium and Aspergillus (8, 23, 29, 31, 32). The advent of PSR has greatly clarified the taxonomy of these genera and as such is a powerful tool for fungal species delimitation. However, this methodology is expensive and requires phylogenetic expertise, which may be limiting factors in clinical microbiology laboratories. In reality, once a species has been delimited by PSR using several robust loci, sequence diversity within the species is known, and on the basis of this knowledge, comparative sequence analyses from a single locus can be used for rapid species identification. “Cutoff scores,” which are dependent on genetic diversity within and between sibling species, can then be provided. Thus, it is important to clarify that our intent in this editorial is to address the practice of species “identification” as applied to a clinical setting and not species “classification” necessary for taxonomic categorization. Although the two terms can be overlapping, the purpose of an “identification” method in a clinical microbiology laboratory is the ability to provide a specific name or epithet to an organism rapidly and with precision, without the complex experimental research or detailed phylogenetic analyses vital for a taxonomic “classification” scheme. Such specific information can then be used by the physician in a decision-making algorithm that can guide patient management. The field of medical mycology has embraced molecular methods of identification, resulting in the exploration of numerous potential targets, an explosion in the number of sequences from these loci, and recognition of previously unknown fungal species adding to the already staggering fungal diversity. On the other hand, this practice may have opened up a number of possibilities, at least from the perspective of a mycologist in a routine microbiology laboratory, resulting in considerable uncertainty about the best possible molecular method to obtain a species identification. Realizing this, a consortium of international experts was assembled as an International Society for Human and Animal Mycology (ISHAM; www.isham.org) working group on fungal molecular identification. With the goal of supporting clinical laboratories in their efforts to identify fungal species from culture by using molecular methods, the ISHAM working group agreed to begin by focusing on molecular strategies available for medically important fungi of the genera Aspergillus and Fusarium and the order Mucorales (Zygomycota). The advantages and limitations of these methods are discussed, and the recommendations of this working group are presented in this editorial.