Table 1.
Provenance, GenBank accession numbers for DNA sequences and MycoBank numbers for species.
Figure 1.
Phylogeny of Talaromyces clade 2a.
Phylogenetic tree of species from part of Talaromyces based on maximum parsimony analysis of RPB2 gene sequences. Bootstrap values above 90% are shown as thick lines in the tree. T. columbinus and T. piceus form strongly supported branches; T. rugulosus, P. chrysitis and P. tardum form a strongly supported branch with T. atricola as sibling; T. scorteus and T. phialosporus form a strongly supported branch. Species on a strongly supported branch that are not well distinguished are potentially synonymous. The tree is rooted with T. proteolyticus on the basis of prior more comprehensive analysis of the genus.
Figure 2.
Genealogical analysis of T. piceus and T. columbinus.
Excised portions of phylogenetic trees based on beta tubulin (BT2), calmodulin (CF), minichromosome maintenance factor 7 (Mcm7) and RNA polymerase beta (RPB2). Bootstrap values above 90% are represented as bold lines. The BT2 tree divides T. piceus and T. columbinus isolates into four statistically supported clades while the other three loci place all T. piceus isolates on a single branch and all T. columbinus isolates on another branch. The BT2 primer set appears to be amplifying different gene fragments or the locus may have undergone rearrangements that make the analysis appear paralogous. Genealogical concordance is seen in a majority of the trees, which supports T. columbinus and T. piceus as distinct species.
Figure 3.
Genealogical concordance analysis.
Excised portions of phylogenetic trees based on beta tubulin (BT2), calmodulin (CF), minichromosome maintenance factor 7 (Mcm7) and RNA polymerase beta (RPB2). Bootstrap values above 90% are represented as bold lines. Talaromyces atricola is sibling to T. rugulosus at each locus supporting it as a distinct species. Penicillium scorteum has in the past been considered a synonym of T. rugulosus but this analysis shows that P. scorteum is conspecific with T. phialosporus.
Figure 4.
Graphical depiction of temperature dependent colony diameter for isolates of T. piceus (blue line) and T. columbinus (red line). T. piceus growth begins at 14.5°C, T. columbinus begins growth at 20°C, at the upper temperature range (44.5°C) T. columbinus colonies are ca 20 mm diam, while T. piceus isolates mostly do not grow. T. columbinus isolates tend to greater colony diameter at most temperatures but with great variation among the isolates.
Figure 5.
Panels A–D show colonies of NRRL 58811 grown 7d with the specified medium and incubation temperature. There is no growth on NaCl amended CYA medium. Cultures incubated at temperature between 30°C and 46°C produce a dark brown soluble pigment in the agar. The color of the CYA culture at 37°C is the basis of the epithet. E. Conidia mostly globose 2.5–3.5 µm diam and smooth walled with occasional much larger and ovoid individuals, bar = 10 µm. F, G. Penicillus structure with vesiculate stipe, metulae and phialides. Conidia often form conical aggregations apically on the penicillus, bar = 10 µm.
Figure 6.
Panels A–D show colonies of NRRL 1051 grown 7 d with the specified medium and incubation temperature. Incubation at 37°C on CYA does not produce the bluish-gray color seen in T. columbinus and exudate is evident on colonies grown at 35–41°C. E. Conidia, subglobose to ellipsoidal, smooth walled 2–2.5×3–3.5 µm. F–H. Penicillus structure very similar to that of T. columbinus including the conical aggregation of conidia at the apex of the penicillus. Bar = 10 µm.