Easily mis-identified as :
Oblong-leaved Sundew (Drosera intermedia) but that has oblong rather than round leaves.
Hybridizes with :
- The less common Great Sundew (Drosera anglica) to produce
Obovate Sundew, but unlike Great Sundew, it grows over a much larger area, occupying mainly the most of the mountains of Scotland.
Oblong-leaved Sundew (Drosera intermedia) to produce
Uniquely identifiable characteristics
Distinguishing Feature : The round leaves should distinguish it from two other sundews, although it does hybridize with them.
No relation to :
Purple Sundew (Disphyma crassifolium) a serpentine rock speciality in the Dewplant Family [Aizoaceae].
Grows in upland acid peat bogs and other wet upland places. It is carnivorous eating insects. See Great Sundew for how it accomplishes this.
Round-leaved Sundew has been used in folk medicines for a long time to treat colds, coughs, bronchitis and asthma. In Italy it is used in a liqueur.
Sundews are carnivorous plants which trap insects in their leaves, dissolve them and absorb the resulting nutrient soup for use by the plant itself. The leaves exhibit Thigmonasty, moving in response to touch. See Great Sundew for modus operandi.
NAPTHOQUINONES and NAPTHAZARINS
The compounds shown below are to be found in many plants of the Drosera Genus (Sundews).
Plumbagin is the major napthoquinone contained within the Drosera Genera, (Sundews) of which Round Sundew is one. Plumbagin is a toxic bright yellow dye which is also found in the blackish drupe (commonly also called a walnut) of the
Walnut tree. Round-leaved Sundew has in the past been used for dying cloth a bright yellow colour in Scotland, when it is known as 'lus-na-fearnaich'.
7-methyl Juglone has the methyl group placed on the opposite ring from that of Plumbagin.
Biramentaceone is the dimer of 7-methyljuglone, repeated again here for direct comparison.
Other napthaquinones contained within Drosera species are
Hydroxydroserone is the only napthazarin shown here. Napthazarines are napthoquinones with two para-positioned OH groups. The glycosides of both Drosereone and 7-Methyljuglone are also present in Sundews.
The Venus Flytrap (Dionaea muscipula), a member of the same Drosearaceae Family that Sundews are in, contains both Diomuscione and Muscipulone, but these compounds are not found in Sundews themselves.