What is "physoceras"

Physoceras is a genus of flowering plants from the orchid family, Orchidaceae. It is native to Madagascar and Réunion; it was also formerly present in Mauritius but now apparently extinct there.

1. Physoceras australe Boiteau - Madagascar
2. Physoceras bellum Schltr. - Madagascar
3. Physoceras betsomangense Bosser - Madagascar
4. Physoceras bifurcum H.Perrier - Madagascar
5. Physoceras boryanum (A.Rich.) Bosser - Mauritius†, Réunion
6. Physoceras castillonii P.Bernet - Réunion
7. Physoceras epiphyticum Schltr. - Madagascar
8. Physoceras lageniferum H.Perrier - Madagascar
9. Physoceras mesophyllum (Schltr.) Schltr. - Madagascar
10. Physoceras perrieri Schltr. - Madagascar
11. Physoceras rotundifolium H.Perrier - Madagascar
12. Physoceras violaceum Schltr. - Madagascar