What is "hormidium"

Within the Orchidaceae, Hormidium was originally a subgenus of the genus Epidendrum, but was later raised to a full genus. It is now considered not to be distinct from the genus Prosthechea, of which it is a synonym. Most of the species of Hormidium have been transferred to Prosthechea, although others are now classified in Encyclia, Epidendrum, Homalopetalum, and Lepanthes.

Hormidium can refer to:

• A group of orchids whose various species have been transferred to Encyclia, Epidendrum, Homalopetalum, Lepanthes, and Prosthechea.
• A genus of algae, an illegitimate name whose application caused confusion, now included in the Prasiolaceae, but the nomenclature is not resolved. Species formerly placed in Hormidium may be listed in different references under the following genera:
  • Chlorhormidium B.Fott, in Ulotrichaceae, an illegitimate name, some species of which have not been resolved
  • Hormococcus Chodat
  • Klebsormidium P.C.Silva, K.Mattox & W.Blackwell, in Klebsormidiaceae
  • Pseudoulothrix Pascher