Triadenum
| Triadenum | |
|---|---|
   | |
| Triadenum virginicum | |
| Scientific classification  | |
| Kingdom: | Plantae | 
| Clade: | Tracheophytes | 
| Clade: | Angiosperms | 
| Clade: | Eudicots | 
| Clade: | Rosids | 
| Order: | Malpighiales | 
| Family: | Hypericaceae | 
| Tribe: | Cratoxyleae | 
| Genus: | Raf.  | 
| Type species | |
| T. fraseri (Spach) Gleason   | |
| Synonyms[1] | |
 
  | |
Triadenum, known as marsh St. John's worts,[2] is a small genus of flowering plants in the family Hypericaceae. The genus is characterized by opposite, blunt-tipped leaves and pink flowers with 9 stamens. They are distributed in North America and eastern Asia.
Acceptance of this genus is varied. Kew's Plants of the World Online[3] and the Database of Vascular Plants of Canada (VASCAN)[4] treat it as a junior synonym of Hypericum and the Flora of North America[1] and Flora of China[5] treat it as separate. The situation arises from B. R. Ruhfel et al. (2011)'s genetic study describing Triadenum as subsumed under Hypericum and later genetic results disagreeing with this assessment.[6] Under Hypericum, the species are mostly treated as the section Hypericum sect. Elodea.[7]
Species
Triadenum contains the following 6 species according to Flora of North America and Flora of China:[1][5]
- Triadenum breviflorum (Wall.)
 - Triadenum fraseri (Spach) Gleason
 - Triadenum japonicum (Thunb.)
 - Triadenum tubulosum (Walter) Gleason
 - Triadenum virginicum (L.) Raf.
 - Triadenum walteri (J.F.Gmel.) Gleason
 
References
- ^ a b c "Triadenum in Flora of North America @ efloras.org". www.efloras.org. Retrieved 2021-12-15.
 - ^ NRCS. "Triadenum". PLANTS Database. United States Department of Agriculture (USDA). Retrieved 14 December 2015.
 - ^ "Triadenum Raf". Plants of the World Online.
 - ^ "Triadenum". VASCAN. Retrieved 17 June 2022.
 - ^ a b "Triadenum in Flora of China @ efloras.org". www.efloras.org.
 - ^ Robson, N. K. (2021). "Studies in the genus Hypericum L.(Hypericaceae) 9. Addenda, corrigenda, keys, lists and general discussion". Phytotaxa. 72: 1–111. doi:10.11646/phytotaxa.72.1.1.
 - ^ Robson, Norman K.B. (11 April 2016). "And then came molecular phylogenetics—Reactions to a monographic study of Hypericum (Hypericaceae)". Phytotaxa. 255 (3): 181. doi:10.11646/phytotaxa.255.3.1.
 
 

.jpg)