Data from: Unravelling species boundaries in the Aspergillus viridinutans complex (section Fumigati): opportunistic human and animal pathogens capable of interspecific hybridization

Although Aspergillus fumigatus is the major agent of invasive
aspergillosis, an increasing number of infections are caused by its
cryptic species, especially A. lentulus and the A. viridinutans species
complex (AVSC). Their identification is clinically relevant because of
antifungal drug resistance and refractory infections. Species boundaries
in the AVSC are unresolved since most species have uniform morphology and
produce interspecific hybrids in vitro. Clinical and environmental strains
from six continents (n = 110) were characterized by DNA se- quencing of
four to six loci. Biological compatibilities were tested within and
between major phylogenetic clades, and ascospore morphology was
characterised. Species delimitation methods based on the multispecies
coalescent model (MSC) supported recognition of ten species including one
new species. Four species are confirmed op- portunistic pathogens; A.
udagawae followed by A. felis and A. pseudoviridinutans are known from
opportunistic human infections, while A. felis followed by A. udagawae and
A. wyomingensis are agents of feline sino-orbital aspergillosis. Recently
described human-pathogenic species A. parafelis and A. pseudofelis are
synonymized with A. felis and an epitype is designated for A. udagawae.
Intraspecific mating assay showed that only minor part of the
heterothallic species can readily generate sexual morph in vitro.
Interspecific mating assay revealed that five different species
combinations were biologically compatible. Hybrid ascospores had atypical
surface ornamentation and significantly different dimensions compared to
parental species. This suggests that species limits in the AVSC are
maintained by both pre- and post-zygotic barriers and these species
display a great potential for rapid adapta- tion and modulation of its
virulence. This study highlights that a sufficient number of strains
representing genetic diversity within a species is essential for
meaningful species boundaries delimitation in cryptic species complexes.
MSC-based delimitation methods are robust and suitable tools for
evaluation of boundaries between these species.