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Aspergillus candidus is a species frequently isolated from stored grain, food, indoor environments, soil and occasionally also from clinical material. Recent bioprospecting studies highlighted the potential of using A. candidus and its relatives in various industrial sectors as a result of their significant production of enzymes and bioactive compounds. A high genetic variability was observed among A. candidus isolates originating from various European countries and the USA, that were mostly isolated from indoor environments, caves and clinical material. The A. candidus sensu lato isolates were characterized by DNA sequencing of four genetic loci, and agreement between molecular species delimitation results, morphological characters and exometabolite spectra were studied. Classical phylogenetic methods (maximum likelihood, Bayesian inference) and species delimitation methods based on the multispecies coalescent model supported recognition of up to three species in A. candidus sensu lato. After evaluation of phenotypic data, a broader species concept was adopted, and only one new species, Aspergillus dobrogensis, was proposed. This species is represented by 22 strains originating from seven countries (ex-type strain CCF 4651 T =NRRL 62821 T =IBT 32697 T =CBS 143370 T ) and its differentiation from A. candidus is relevant for bioprospecting studies because these species have different exometabolite profiles. Evaluation of the antifungal susceptibility of section Candidi members to six antifungals using the reference EUCAST method showed that all species have low minimum inhibitory concentrations for all tested antifungals. These results suggest applicability of a wide spectrum of antifungal agents for treatment of infections caused by species from section Candidi.

Talaromyces strains isolated from maize seeds and the built environment were examined taxonomically because they could not be identified as previously described species. Using phenotypic analysis, DNA sequencing, and phylogenetic and concordance analyses, the authors discovered and described 10 new species in sect. Islandici and 1 new species in sect. Subinflati. Taxonomic novelties in sect. Islandici are Talaromyces delawarensis, T. herodensis, T. juglandicola, T. kilbournensis, T. novojersensis, T. ricevillensis, T. rogersiae, T. siglerae, T. subtropicalis, and T. tiftonensis, and the species from sect. Subinflata is T. tzapotlensis. The isolate of T. siglerae is unusual in Talaromyces because it produced a Sagenomella-like anamorph, but phylogenetic analysis placed it in Talaromyces. Talaromyces rotundus is known from a few isolates, but searches with internal transcribed spacer (ITS) sequences in GenBank revealed that it is commonly endolichenous with Lasallia hispanica. Talaromyces wortmannii also has a role as an endophyte of the aquatic plant Persicaria amphibia, based on ITS sequence records from GenBank.

During mould surveys a number of Aspergillus strains were isolated from environmental air which did not fit any known species of the genus. They showed phenotypic as well as molecular genetic similarity with A. arenarius, A. arenarioides and A. peyronelii, three species without clear phylogenetic position. Multi-gene phylogenetic analysis comprising taxa across the subgenus Circumdati showed that these species cluster into a well-supported clade sister to sect. Candidi. We propose the status of a new section for this clade, sect. Petersonii sect. nov. The phenotypic descriptions after 14 days on 8 various agar media were provided for members of sect. Petersonii which, together with maximum growth temperature and molecular genetic data from four loci (ITS rDNA, β-tubulin, calmodulin and RPB2) supported the recognition of four species. Two species are newly described here as A. asclerogenus sp. nov. and A. petersonii sp. nov. Aspergillus arenarius is reduced to synonymy with A. peyronelii, a species revived and typified in this study. A dichotomous key based on the combination of morphology and physiology is provided for all recognized species of sect. Petersonii. In addition, other species from subg. Circumdati with ambiguous phylogenetic position based on previous studies were also included in our analysis resulting in the proposal of sections Robusti and Tanneri. All newly proposed sections also have strong phenotypic support. [ABSTRACT FROM AUTHOR]