Pleurostomophora richardsiae
Synonymy:
Phialophora richardsiae
Vijaykrishna et al. (2004) separated Pleurostomophora richardsiae from Phialophora based on molecular data. P. richardsiae is a soft rot fungus of wood and is an uncommon cause of human infection, usually through traumatic implantation causing subcutaneous phaeohyphomycosis.
RG-2 organism.
Morphological Description:
Colonies grow rapidly, and are powdery to woolly or tufted, greyish-brown with a grey-brown to olivaceous-black reverse. Two conidial types are produced: (1) hyaline conidia which are allantoid or cylindrical, 3-6 x 1.5-2.5 μm in size, formed on inconspicuous, peg-like phialides on thin-walled hyphae; and (2) brown, thick-walled conidia which are spherical to subspherical, 2.5-3.5 x 2-3 μm, formed on dark brown, slender, tapering phialides with flaring collarettes.
Key Features:
P. richardsiae is characterised microscopically by phialides with prominent flaring collarettes bearing globose, brown conidia while phialides with indistinct collarettes bear pale allantoid to cylindrical conidia.
Molecular Identification:
ITS sequencing is recommended (Vijaykrishna et al. 2004).
References:
Ellis (1971), McGinnis (1978a, 1980), Domsch et al. (1980), de Hoog et al. (2000, 2015), Vijaykrishna et al. (2004), Revankar and Sutton (2010).
Antifungal Susceptibility: Pleurostomophora richardsiae limited data (Australian National data); MIC µg/mL. |
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No | <0.03 | 0.06 | 0.125 | 0.25 | 0.5 | 1 | 2 | 4 | 8 | 16 | >32 | |
AmB | 7 | 1 | 1 | 4 | 1 | |||||||
VORI | 7 | 3 | 4 | |||||||||
POSA | 5 | 1 | 2 | 2 | ||||||||
ITRA | 7 | 2 | 3 | 2 | ||||||||
P. richardsiae data from 11 isolates (McGinnis and Pasarell 1998a); MIC µg/mL. | ||||||||||||
AmB | Range 0.125-1; Geometric mean = 0.73 | |||||||||||
VORI | Range 0.25-2; Geometric mean = 0.64 | |||||||||||
ITRA | Range 0.03-2; Geometric mean = 0.44 |