<prompt> Black Piedra is caused by:Pityrosporum orbiculareExophialaTrichosporon beigeliiPiedraia hoae  <response>: Black piedra Caused by Piedraia hoae Gross-Discrete black, gritty, hard nodules on the hair of the scalp Dx- 10 KOH mount of the crushed nodule reveals dark septate hyphae with club shaped asci, each containing 2-8 ascospores 