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Ochroconis 

Recently, the genus Ochroconis has undergone taxonomic revision, and the most relevant species, Ochroconis gallopava, was transferred to the new genus Verruconis (Samerpitak et al. 2014). Ochroconis species are mesophilic saprobes, with an optimum growth temperature between 15 and 30C and an inability to grow at 37C. Nevertheless, some species have been isolated from clinical specimens; such as Ochroconis tshawytschae, O. mirabilis, O. cordanae, O. olivacea and O. ramosa (Samerpitak et al. 2014, Seyedmousavi et al. 2014, Giraldo et al. 2014). Note: Species described in the literature from clinical cases as O. constricta or O. humicola are probably O. musae Samerpitak et al. 2014).

Giraldo et al. (2014) reported on the occurrence of Ochroconis and Verruconis species in clinical specimens from the United States. V. gallopava was the most common species (69%), followed by O. mirabilis (22%). Other species isolated were O. cordanae, O. olivacea and O. ramosa. The most common anatomical site of isolation was the lower respiratory tract (59%), followed by superficial (22%) and deep tissues (20%) (Giraldo et al. 2014).

RG-1 organisms.

Morphological Description: 
Colonies restricted, velvety to funiculose, brown to olivaceous, often with rust-brown reverse. Hyphae smooth- or somewhat rough-walled, pale olivaceous. Conidiophores slightly or conspicuously differentiated, cylindrical, often flexuose, producing conidia on scattered, cylindrical to conical denticles. After detachment an inconspicuous frill often remains both on the denticle and on the conidium base. Conidia one to four-celled, pale olivaceous brown, smooth- or rough-walled, ellipsoidal, cylindrical, clavate or cuneiform. Maximum growth temperature around 33C.

Molecular Identification: 
Giraldo et al. (2014) used sequence analyses of the 18S, ITS, D1/2, actin, and β-tubulin genes, while Seyedmousavi et al. (2014), used ITS sequence analyses to identify species.

References: 
de Hoog et al. (2015), Samerpitak et al. (2014), Seyedmousavi et al. (2014), Giraldo et al. (2014).

Antifungal Susceptibility: Ochroconis mirabilis variable data for posaconazole, caspofungin and anidulafungin from Seyedmousavi et al. (2014)1 and Giraldo et al. (2014)2; MIC µg/mL.
Antifungal Range MIC90 Antifungal  Range MIC90
AmB 1-32 32 VORI 0.06-0.25 1
0.05-32 2
-
32
ITRA 0.25-32 32 POSA 2-32 32
CAS 0.5-1 1
1-32 
-
4
ANID 0.03-0.125 1
0.015-32 2
-
4
MICA 0.06-0.50 0.25 TERB 0.015-0.125 0.02

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