Triadenum tubulosum (Walt.) Gleason
Show image without county labels
Detail
- Family
- Hypericaceae
- Botanical Name
- Triadenum tubulosum (Walt.) Gleason
- Common Name
- Lesser Marsh St. John's-wort
- Synonym(s)
- Hypericum tubulosum Walter
- Flora of Virginia Name/Status
- Triadenum tubulosum (Walt.) Gleason
- Comments
- This species can be readily distinguished from its similar congeners Triadenum virginicum and T. walteri by the lack of punctate glands on its foliage. Its sessile leaves are somewhat variable; the upper leaves of well-grown plants are often rounded to somewhat cordate at base while lower leaves and leaves of small plants are usually cuneate to a narrower base.
The proper disposition of plants in the genus Triadenum may be still unresolved, as they have been recently treated in both Hypericum and Triadenum. Based on a comprehensive phylogenetic study of Hypericum (sensu lato), Nürk et al. (2013, Molec. Phylogen. & Evol. 66: 1-16) included Triadenum in Hypericum, but the position of Triadenum as a somewhat basal clade and the inclusion of Triadenum japonicum suggests that the fairly ancient, eastern North American - east Asian vicariance had elements that were clearly similar to one another and distinct from other Hypericums long ago. The morphological distinctions of Triadenum lend further credence to its treatment as a separate genus. - Habitat
- Bottomland forests and swamps, usually in seasonally flooded sloughs and depressions. Widespread, but infrequent to rare in the southern and central parts of the inner Coastal Plain and outer Piedmont. Very rare elsewhere.
- Native Status
- Native
To save this map, right-click (control-click for Mac users) on the map and choose "Save Image As...".