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Remarks (public):For a complete description including images see 
Remarks (internal):Phialophora verrucosa is one of the causal agents of chromoblastomycosis, in which the fungal elements exist as muriform cells with both horizontal and longitudinal septa; these are sometimes referred to as sclerotic cells or microsclerotia. This morphology differs from that of the other species of Phialophora causing mycoses which have a hyphal form. Use of tricyclazole has proved that the pentaketide pathway is the route to cell wall melanization (23, 204). Many anti-fungal agents are effective against P. verrucosa including azole derivatives (13, 866; 26, 67), 5 fluorouracil [SFU] (18, 982), aculeacin A (19, 58), nitrosofungin (2-N-nitrosohydroxylamino-1-propanol) (19, 1114) and Amphotericin-B used synergistically with fluorocytosine (18, 2423). Local heat therapy has also been suggested as a treatment (21, 1591). Lipase may have a role in pathogenicity (25, 1986). Inoculation of an alkali-insoluble cell wall fraction induced granulomatous reaction and death in laboratory mice (21, 838). Phialophora verrucosa is also an agent causing blueing of timber and has been isolated from a variety of sources e.g. plant debris, wood and soil (8, 779; 17, 873; 21, 1607). Much literature regarding this fungus can also be found under the synonym P. americana; various physiological studies have concluded that this synonymy is justified (21, 840).
Description type:Non-original description 
Description:Phialophora verrucosa Medlar, Mycologia 7: 203, 1915.
Cadophora americana Nannf., 1934.
Phialophora americana (Nannf.) S. Hughes, 1958.
Colonies on PCA 2,5 cm diam. after 10 d, olivaceous grey, velvety, raised and dense at the centre, with a diffuse hyaline margin, reverse dark brown to black in older cultures. Conidiophores poorly differentiated, arising in the aerial mycelium as sparse lateral branches of vegetative hyphae or of torulose mycelium, light brown or olivaceous, giving rise to conidiogenous cells laterally and terminally. Conidiogenous cells discrete, mostly flask-shaped, light brown or olivaceous, 10-25 x 4-5 µm, terminating in a pronounced, dark, cup-shaped collarette, producing conidia enteroblastically, singly, and successively at the apex, partly within the collarette. Conidia hyaline, broad-ellipsoidal, 3-6 x 1,5-3 µm, aggregating in heads.
Hosts: Man, Felis, Equus.
Disease: Chromomycosis (chromoblastomycosis) subcutaneous and systemic.
Geographical distribution: Africa: Algeria, Kenya, Nigeria, South Africa; Asia: China, India, Indonesia, Japan, Malaysia, Philippines; Europe: Finland, France, Israel, Sweden, Turkey, U.K., USSR; North America: USA (widespread), Canada (Ontario); Central & South America: Argentina, Brazil, Costa Rica, Colombia, Cuba, Ecuador, Mexico, Paraguay, Uruguay, Venezuela; Australasia: Australia.
Physiologic specialization: None reported.
Transmission: Generally infection is from plant debris etc. following cutaneous trauma, the fungus generally remaining localised at the point of entry, or spread via the lymphatic system to cause systemic infection. The fungus is widespread in soils etc.

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