DESCRIPTIONS OF MEDICAL FUNGI
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Descriptions of Medical Fungi 131<br />
Mucor Micheli ex Staint-Amans<br />
The genus Mucor contains about 50 recognised taxa, many of which have widespread<br />
occurrence and are of considerable economic importance (Zycha et al. 1969, Schipper<br />
1978, Domsch et al. 1980). However, only a few thermotolerant species are of medical<br />
importance and human infections are only rarely reported. Most infections reported<br />
list M. circinelloides and similar species such as M. indicus, M. ramosissimus, M.<br />
irregularis and M. amphibiorum as the causative agents. However, M. hiemalis and<br />
M. racemosus have also been reported as infectious agents, although their inability to<br />
grow at temperatures above 32 O C raises doubt as to their validity as human pathogens<br />
and their pathogenic role may be limited to cutaneous infections (Scholer et al. 1983,<br />
Goodman and Rinaldi 1991, Kwon-Chung and Bennett 1992, de Hoog et al. 2000,<br />
2015).<br />
Maximum temperature for growth of the reported pathogenic species of Mucor.<br />
Species Max temp. ( O C) Pathogenicity<br />
M. amphibiorum 36 Animals, principally amphibians<br />
M. circinelloides 37 Animals, occasionally humans<br />
M. hiemalis 30 Questionable cutaneous infections only<br />
M. indicus 42 Humans and animals<br />
M. irregularis 38 Humans<br />
M. racemosus 32 Questionable<br />
M. ramosissimus 36 Humans and animals<br />
Morphological Description: Colonies are very fast growing, cottony to fluffy, white to<br />
yellow, becoming dark-grey, with the development of sporangia. Sporangiophores are<br />
erect, simple or branched, forming large (60-300 µm in diameter), terminal, globose<br />
to spherical, multispored sporangia, without apophyses and with well-developed<br />
subtending columellae. A conspicuous collarette (remnants of the sporangial<br />
wall) is usually visible at the base of the columella after sporangiospore dispersal.<br />
Sporangiospores are hyaline, grey or brownish, globose to ellipsoidal, and smoothwalled<br />
or finely ornamented. Chlamydospores and zygospores may also be present.<br />
Key Features: Mucorales, large, spherical, non-apophysate sporangia with<br />
pronounced columellae and conspicuous collarette at the base of the columella<br />
following sporangiospore dispersal.<br />
Molecular Identification: ITS sequencing recommended (Walther et al. 2012).<br />
References: Schipper (1978), Domsch et al. (1980), McGinnis (1980), Onions et al.<br />
(1981), Scholer et al. (1983), Rippon (1988), Goodman and Rinaldi (1991), Samson<br />
et al. (1995), de Hoog et al. (2000, 2015), Schipper and Stalpers (2003), Ellis (2005b).