Thermal dimorphism in P. marneffei. A) The mould phase of P. marneffei depicting phialides bearing typical conidia (slide culture incubated at 25°C). B) Thin, multiply branched hyphae developing from conidia (arrows) incubated in SDB for 24 hours at 25°C. C) Short, broad hyphae generated from conidia (arrows) incubated in SDB for 24 hours at 37°C. D) Yeast cells of P. marneffei produced from conidia incubated in SDB for 96 hours at 37°C. The size bar in frame A, representing 20 μm, is applicable to each individual photomicrograph.