Johan Rutger Sernander (2 November 1866 – 27 October 1944) was a Swedish botanist, geologist and archaeologist.

He was one of the founders of the study of palynology which would later be developed by Lennart von Post, as well as a pioneer in the early Swedish natural conservation and ecology movements.

[2] Sernander was one of the founders of the Swedish Society for Nature Conservation in 1909, as well as its chairman during a number of the first years.

[4] He was married to Signe Lindhagen and they had one daughter, Greta Sernander-DuRietz.

(now Leptogium rivulare),[5] which he found around 1914 but the type specimen was probably collected later by his daughter.