A revision of the red-flowered Cyrtandra terrae-guilelmi complex (Gesneriaceae) in New Guinea, with the description of five new species.

Cyrtandra J.R.Forst. & G.Forst. (Gesneriaceae) are widespread in New Guinea, with most of the ~92 species recognised species endemic to the island. However, New Guinea Cyrtandra have not received a taxonomic revision since Schlechter in 1923, who recognised 14 sections. A taxonomic revision of the red-flowered Cyrtandra terrae-guilelmi K.Schum. species complex (within Schlechter’s Cyrtandra sect. Loxanthe) is presented here, encompassing C. terrae-guilelmi (syn. C. schumanniana Schltr.), C. gorumensis Schltr., C. wilhelmensis P.Royen and five new species that are seemingly closely related: Cyrtandra asekiensis S.Hatt & Bramley, Cyrtandra buloloensis S.Hatt & Bramley, Cyrtandra ferruginicalyx S.Hatt & Bramley, Cyrtandra huonensis S.Hatt & Bramley and Cyrtandra milneensis S.Hatt & Bramley. This work forms part of a broader taxonomic revision of New Guinea Cyrtandra.