552 MEDICAL MYCOLOGY 



Arthrosporia Grrigorakis, Ann. Sci. Nat. Bot. X, 7: 414, 1925. 



Type species: Achorion Schoenleini (Lebert) Remak. 



Chlamydospores and aleurospores usually present, sometimes also clos- 

 terospores, liyphal tips often swollen forming favic candelabra; giant colonies 

 rarely powdery, usually cottony or even moist ; lesions usually with typical 

 favic scutula, hair dull grayish, splitting longitudinally, rarely inflammatory 

 on normal host, usually so on occasional hosts. 



As in Microsporum, we have a degeneration series in this genus. In the 

 first subgenus, which we may call Lophophyton, there are a wide range of hosts, 

 more inflammatory lesions, and greater diversity of spore forms in the life 

 cycle. In the subgenus Euachorion there is greater host specialization, little or 

 no inflammatory processes, usually only chlamydospores and arthrospores 

 present. 



The recent classifications based on morphology of spores have attempted 

 to distribute the section Lophophyton between Microsporum and Ectotrichophy- 

 ton and have either recognized Euachorion (often under another name) as a 

 separate genus, or transferred it to Favotrichophyton. 



Key to Species 



Closterospores and aleurospores present, attacking a variety of domestic animals as well as 

 man and producing typical scutula on several, or if scutula are not produced, lesions 

 are inflammatory. lophophyton. 



Colony powdery, cafe-au-lait in color, margin white. 



Margin of lanceolate rays, cottony j eccentric oval furrow; center a small button, 

 pleomorphic mycelium white; nodular organs present. 



A. gypse/wm. 

 Margin without rays, no oval furrow, center irregularly elevated, reverse golden 

 yellow; pleomorphic colony tinted color of wine lees. 



A. Serisei. 

 Colony violaceous; center elevated, margin a rosette of compact hyphae. 



A. violacemn. 

 Colony varying from white at room temperature to rose color at 30° C, in some cultures 

 even raspberry; pigment diffusing into the medium; on conservation medium 

 with 3-4 fine concentric folds about a slight central depression. 



A. gulUnae. 

 Colony pure white with sliort marginal fringe, rough with more or less concentric furrows 

 with some irregular hills and channels about the margin; reverse yellowish white 

 at room temperature, deep violet at 35° C. A. muris. 



Colony dirty white, becoming yellowish, waxy, center elevated, surrounded by a flat waxy 

 zone and margin of submersed rays suggesting cypress leaves, reverse bright 

 yellow. A. anpressiforme. 



Closterospores absent, usually also aleurospores, usually attacking only one domestic animal 

 or man and rarely producing typical scutula on more than one host, although 

 sometimes inoculable into several hosts, usually lesions not inflammatory; colony 

 usually moist, irregularly folded. euachorion. 



Colony bright yellow becoming brownish; favic scutula grayish white; nodular organs 

 present; inoculable to guinea pig not mouse, ape, or hen. 



A. formosev/in. 

 Colony yellowish white; favic scutula bright yellow; no nodular organs; inoculable to 

 guinea pig, rat, mouse, cat, and rabbit. A. Schoenleini. 



