Siegfried Reissek (11 April 1819 in Teschen – 9 November 1871 in Vienna) was an Austrian naturalist and botanist who specialized in spermatophytes.
He is known for his studies involving plant anatomy and histology.
He worked as assistant curator at the Royal Botanical Collection in Vienna between 1845 and 1867, when he was appointed head curator; and from 1848 was a member of the Vienna Academy of Sciences.
[2] He circumscribed numerous plant taxa, including the genus Stenanthemum (family Rhamnaceae).
[3] The plant genus Reissekia from Brazil (in the family Rhamnaceae) commemorates his name.