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Aspergillus section Nidulantes is a speciose group of microscopic fungi whose species are important in indoor air quality, food spoilage, mycotoxin production and human pathogenicity. We assembled as many species from the section as possible with either type specimens or protologues for analysis. DNA sequences were obtained from up to four loci to conduct phylogenetic analysis of sect. Nidulantes and other species in subgenus Nidulantes. Comparisons of phenetic characters were made. Our goal was to recognize monophyletic taxa for section Nidulantes as well as the other taxa in the subgenus. Phylogenetic analysis indicated that sections Versicolores and Aenei formed subclades in the larger clade containing the type species of section Nidulantes. In order to maintain monophyly in section Nidulantes, we synonymized sects. Versicolores and Aenei with sect. Nidulantes. In place of sections, we have identified six subclades in sect. Nidulantes that also have shared phenetic character sets that allow for easier morphological identification of species. Earlier reports showed that standard β-tubulin primers can occasionally amplify the tubC gene rather than the benA gene they were designed for. We show that codon usage analysis can easily distinguish between these paralogues, and we provide primer pair options to allow benA amplifications. Two new sect. Nidulantes species are described from European caves, A. croceus (Spain) and A. askiburgiensis (Czech Republic). The analysis of exometabolites showed that both species are able to produce the mycotoxin sterigmatocystin and some additional compounds.

The tribeDrypeteae, whose traditional assignment inPhyllanthoideae ofEuphorbiaceae is now doubtful, is studied embryologically on the basis of a literature survey and examination of six additional species in two of the four constituent genera.Drypeteae are characterized by having several embryological features that are unknown in otherPhyllanthoideae, such as a two- or three-celled ovule archesporium; a thin, two cell-layered parietal layer in the nucellus; no nucellar beak or cap; an early disintegrating nucellar tissue; thick, multiplicative, inner and outer integuments; an endothelium; a few discrete vascular bundles in the outer integument; and a fibrous exotegmen (or its derived state). EmbryologicallyDrypeteae do not fit within thePhyllanthoideae and, as available nucleotide sequence data from therbcL gene suggest, are rather placed nearErythroxylaceae, Rhizophoraceae, Chrysobalanaceae, andLinaceae. Drypeteae share with those families a combination of the fibrous exotegmen, the endothelium, and the thick, multiplicative inner integument.

Species delimitation has been a major research focus in evolutionary biology. However, the genetic delimitation of recently diverged species varies depending on the markers examined. In this study, we aimed to examine genetic differentiation and delimitations between only two species of Pugionium Gaertn (Brassicaceae)—Pugionium cornutum (L.) Gaertn and Pugionium dolabratum Maxim—that occur in the desert habitats of central Asia and have parapatric distributions. We genotyped 169 individuals from 25 populations, using two chloroplast (cp) DNA fragments (trnV-trnM and trnS-trnfM), seven simple repeated sequence (SSR) loci and the nuclear ribosomal internal transcribed spacer (ITS). Four cp haplotypes were identified, three of which commonly occur in the two species, suggesting incomplete species-specific lineage sorting. Between-species cpDNA differentiation (F CT) was low, even lower than among populations of the same species. However, we found higher than average SSR F CT values, and both Bayesian clustering of SSR variables and maximum-likelihood genetic analyses divided all sampled individuals into two groups, agreeing well with morphological separation, although gene flow between species was obvious according to the SSR loci data. However, two types of ITS sequences were highly consistent with the morphological delimitation of the two species in all sampled individuals. These results together suggest that these two species shared numerous ancestral cpDNA polymorphisms and point to the importance of nuclear DNA (ITS or genetic accumulation at multiple loci) in delimiting recently diverged species.