Tuesday 19 April 2011

Syncephalastrum species

Syncephalastrum species
-A filamentous fungus classified within the order Mucorales.

Ecology;
Syncephalastrum species are saprobes commonly isolated from animal dung and soil primarily in tropical or subtropical regions.

Macroscopic;
Very rapid growth - mature within 3 days. Abundant aerial hyphae gives a wooly or cotton candy-like texture. Pale to dark grey shades on the surface with a white or pale reverse.

Syncephalastrum on Sabouraud's Dextrose Agar at 72 hrs at 30C
Microscopic;
  • Broad hyphae -septa absent or rare.
  • Sporangiophores are 10-25 µm wide, often branched, having a terminal vesicle up to 80 µm in diameter, which produce finger shaped merosporangia (4-6 µm by 9-35 µm) over the entire surface.
  • Sporangiospores (merospores) are round and formed in a linear series, between 3 to 18 in number within in the interior of the merosporangia. They are smooth in texture, pale brown, spherical to oval, ~3-7 µm in diameter.
  • Rhyzoids are usually present
Sporangiophore arising from hyphae with terminal vesicle with merosporangia radiating out from the surface. (LPCB X400)
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Mature Syncephalastrum sporangiophores (LPCB x400)
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Ditto
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Syncephalastrum sporangiophore with radiating finger-like merosorangia containing individual merospores.
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Finger-like merosporangia free of sporangiophore, each containing merospores
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Pathogenicity;
Considered to be non-pathogenic to humans although a case of cutaneous infection has been reported (Kalama & Thambiah 1980). May be found as a contaminant.