DESCRIPTIONS OF MEDICAL FUNGI

136
Descriptions of Medical Fungi
Myrmecridium schulzeri (Sacc.) Arzanlou et al.
Synonymy: Ramichloridium schulzeri Stahel ex de Hoog.
Ramichloridium schulzeri was placed in a new genus, Myrmecridium by Arzanlou et al.
(2007). M. schulzeri is an uncommon soil saprophyte of worldwide distribution. It has
also been isolated from plant detritus and as a contaminant of bronchoscopy fluid. It
is the causative agent of “Golden Tongue” syndrome reported by Rippon et al. (1985).
RG-1 organism.
Morphological Description: Colonies growing moderately rapidly, consisting of a
rather compact, flat, submerged mycelium, pale orange, locally with some powdery,
brownish aerial mycelium; reverse pink to orange. Conidiophores are erect, straight,
unbranched, thick-walled, reddish-brown, up to 250 µm high, gradually becoming paler
towards the apex, of variable length, elongating sympodially during conidiogenesis, with
scattered, pimple-shaped conidium bearing denticles which have unpigmented scars.
Conidia are subhyaline, smooth-walled or slightly rough-walled, ellipsoidal, obovoidal
or fusiform, 6.5-10 x 3-4 µm, usually with an acuminate base and unpigmented scars.
Molecular Identification: ITS and D1/D2 sequencing may be used for accurate
species identification (Halliday et al. 2015).
Note: Myrmecridium species can be distinguished from other Ramichloridium-like fungi
by having entirely hyaline vegetative hyphae, and widely scattered, pimple-shaped
denticles on the long hyaline rachis. The conidial sheath is also visible in lactic acid
mounts with bright field microscopy Arzanlou et al. (2007).
References: de Hoog (1977), Rippon et al. (1985), de Hoog et al. (2000, 2015),
Arzanlou et al. (2007).
10 µm
20 µm
Myrmecridium schulzeri conidiophores showing sympodial development of conidia.