Heinrich Simon Ludwig Friedrich Felix Rehm (20 October 1828, Ederheim – 1 April 1916, Munich) was a German mycologist and lichenologist. He studied at the Universities of Erlangen, Munich and Heidelberg, earning his medical doctorate in 1852. During his career, he was a practicing physician in Dietenhofen (from 1854), Sugenheim (from 1857), and Windsheim (from 1871). In 1875, he became regional medical examiner in Lohr am Main. Starting with 1869 until his death Rehm distributed exsiccata specimens in five series, one of them co-edited by Ferdinand Christian Gustav Arnold.

Publications (including published schedae of his exsiccata works)

Eponyms

In 1861, the fungal genus Rehmia was named after him by lichenologist August von Krempelhuber, it is now a synonym of Rhizocarpon. Other mycological genera that were named after him include; Rehmiella, Neorehmia now Trichosphaerella, Rehmiellopsis now Delphinella, Rehmiodothis , Discorehmia and Rehmiomycella.