DESCRIPTIONS OF MEDICAL FUNGI

146
Descriptions of Medical Fungi
Paecilomyces marquandii (Massee) Hughes
Paecilomyces marquandii is a soil fungus of worldwide distribution from temperate to
tropical regions.
RG-1 organism.
Morphological Description: Colonies are fast growing, suede-like to floccose, pale
vinaceous to violet-coloured, with a yellow to orange yellow reverse. Conidiophores are
erect, arising from submerged hyphae, 50-300 µm in length, bearing loose whorls of
branches and phialides. Conidiophore stipes are 2.5-3.0 µm wide, hyaline and smoothwalled.
Phialides are swollen at their bases, tapering into a thin, distinct neck. Conidia
are ellipsoidal to fusiform, smooth-walled to slightly roughened, hyaline to purple in
mass, 2.5-3.0 x 2-2.2 µm. Spherical to ellipsoidal chlamydospores, 3-5 µm diameter
are present. No growth at 37 O C.
Key Features: Colony pigmentation with yellow reverse pigment, phialides with swollen
bases, smooth conidiophore stipes, presence of chlamydospores, and no growth at
37 O C. Note: Purpureocillium lilacinum has no yellow reverse pigment, rough-walled
conidiophore stipes, absence of chlamydospores and growth at 37 O C.
References: Samson (1974), Domsch et al. (1980, 2007), de Hoog et al. (2000, 2015).
20 µm
Paecilomyces marquandii conidiophores, phialides and conidia.
Antifungal Susceptibility: P. marquandii (Australian National data); MIC µg/mL.
No. 64
AmB 7 1 1 1 1 3
VORI 4 1 2 1
POSA 2 1 1
ITRA 7 1 2 2 1 1