OregonFlora: Drosera vs. Drosera rotundifolia

	Drosera	Drosera rotundifolia
	sundew	roundleaf sundew
Habit	Herbs often reddish or brownish.
Leaves	adaxial surfaces and margins covered in gland-tipped hairs; long-petiolate.	spreading; round to broadly obovate-cuneate; (4)6–12 × (4)6–12 mm, abruptly narrowed at base or ± cordate; petioles 2–9 cm.
Scapes		7–25 cm.
Inflorescences	usually simple but may be forked.	1–several; (1)3–10-flowered.
Flowers	white to pink.	calyces fused at base, 4–6 mm; petals 3–6 mm, white to pink; styles bifid to base.
Seeds	usually with a loose seed coat that often forms a jointed to flattened wing at one or both ends.	1–1.5 mm, light brown; seed coats finely and regularly longitudinally striate, prolonged and distinctly flattened at each end.
2n		=20.

	Drosera	Drosera rotundifolia
Distribution	[BONAP county map]	[WildflowerSearch map] [BONAP county map]
Discussion	Nearly worldwide. ~90 species; 2 species treated in Flora. The flowers of many species, including ours, close at night and on overcast days.	Swamps, bogs, wet meadows, wet forests, especially in sphagnum. Flowering May–Sep. 0–2900 m. Casc, CR, Est, Sisk, WV. CA, ID, WA; northern North America and most states east of the Mississippi River; Asia, Europe. Native. See D. anglica discussion.
Source	Flora of Oregon, volume 1	Flora of Oregon, volume 2, page 609 Tamra Prior
Sibling taxa		D. anglica
Subordinate taxa	D. anglica, D. rotundifolia
Web links	Local floras: CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria, Turner Photog. WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria, Turner Photog. WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Drosera rotundifolia

sundew

roundleaf sundew

Habit

Herbs often reddish or brownish.

Leaves

adaxial surfaces and margins covered in gland-tipped hairs; long-petiolate.

spreading; round to broadly obovate-cuneate; (4)6–12 × (4)6–12 mm, abruptly narrowed at base or ± cordate;

petioles 2–9 cm.

Scapes

7–25 cm.

Inflorescences

usually simple but may be forked.

1–several; (1)3–10-flowered.

Flowers

white to pink.

calyces fused at base, 4–6 mm;

petals 3–6 mm, white to pink;

styles bifid to base.

Seeds

usually with a loose seed coat that often forms a jointed to flattened wing at one or both ends.

1–1.5 mm, light brown;

seed coats finely and regularly longitudinally striate, prolonged and distinctly flattened at each end.

=20.

Drosera rotundifolia

Distribution

[BONAP county map]

[WildflowerSearch map]

[BONAP county map]

Discussion

Nearly worldwide. ~90 species; 2 species treated in Flora.

The flowers of many species, including ours, close at night and on overcast days.

Swamps, bogs, wet meadows, wet forests, especially in sphagnum. Flowering May–Sep. 0–2900 m. Casc, CR, Est, Sisk, WV. CA, ID, WA; northern North America and most states east of the Mississippi River; Asia, Europe. Native.

See D. anglica discussion.

Source

Flora of Oregon, volume 1

Flora of Oregon, volume 2, page 609
Tamra Prior

Sibling taxa

D. anglica

Subordinate taxa

D. anglica, D. rotundifolia

Web links