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differences between D. intermedia and D. capillaris

I was wondering if anyone could provide a sure fire way of distinguishing whether or not it is a D. intermedia and D. capillaris. Please keep in mind I live in Florida where we supposedly have some weird varieties of D. capillaris that resemble D. intermedia, long skinny petioles, size, etc.

Does anyone have any information on hybrids between the two as well? I visit a local bog here that has a very large population of D. intermedia and D. capillaris growing side by side. I suspect this might be causing a lot of confusion for me. Thank you for your time and input!
 
in my experience capillaris leaves takes on a much rounder spoon-like shape at the tip where intermedia are a bit more elongated with overall longer leaves. intermedia also tend to form more upright leaves whereas capillaris are ground-huggers.
 
ditto what safety shears said, but I would add that some capillaris do put out more upright leaves especially the "long arm" forms however, they do eventually hug the ground. The largest capillaris I've ever seen was probably and inch and a half in diameter and the largest intermedia was probably close to 3 inches in diameter. Also try looking through www.cpphotofinder.com there are tons of photos there for you to compare.
 
D. intermedia likes to grow in water, too. It can still be found on land, but it prefers to grow at the water's edge.
 
The biggest difference is in the flowers and seeds. These characteristics are used in the key for North America Drosera.

Refer to:

DROSERACEAE, the Sundew Family.
(C) 1952 THE NEW YORK BOTANICAL GARDEN Second printing slightly revised. 1958 From Britton & Brown Illustrated Flora Vol. 2
By Henry A. Gleason, Ph.D. Head Curator, The New York Botanical Garden, with the assistance of specialists in certain groups.


Flowers white, 7-8 mm. wide; seeds irregularly and densely covered with
long papillae, 0.7-1 mm. long. 5. D. intermedia

Flowers pink, 10 mm. wide; seeds papillose-corrugated with 14-16 ridges,
0.4-0.5 mm. long. 6. D. capillaris​

5. Drosera intermedia Hayne. Stem 1-8 cm. long, bearing leaves in a rosette or also at intervals for several centimeters along the stem. Petioles 2-5 cm. long, glabrous. Leaf-blades oblong-spatulate to obovate, 4-5 mm. wide, 8-20 mm. long, bearing long glandular hairs on the upper surface. Stipules adnate at the base for the first millimeter, then breaking into several setaceous segments 2-5 mm. long. Sepals oblong, 3-4 mm. long. Petals 4-5 mm. long. Seeds reddish brown, oblong, 0.7-1 mm. long, blunt at the ends, densely and irregularly covered with long papillae.

Northeastern N. Am.; around the Great Lakes and along the coast from Nf. to Tex. July, Aug. [D. longifolia, Gray.]

6. Drosera capillaris Poir. Petioles 0.6-4 cm long, sparsely glandular- pilose. Leaf-blades broadly spatulate, 5-10 mm. long, 3-5 mm. wide, usually shorter than the petioles. Stipules free, or adnate for the first millimeter, then breaking into numerous setaceous segments 3-5 mm. long. Scape glabrous, 4-20 cm. long, Bearing 2-20 flowers. Flowers pink, 10 mm. wide. Sepals oblong-elliptic, 3-4 mm. long, obtuse. Petals 6-7 mm. long. Capsule 4-5 mm. long, surpassing the calyx. Seeds brown, elliptic to oblong-ovate, 0.4-0.5 mm. long, asymmetric, coarsely papillose-corrugated in 14-16 ridges.

Common in the coastal area from se. Va. to Tex. May - Aug:

Learn how to "key a species out" (see the section in Times Courier font in above link) and whole new worlds open up to you. This also illustrates the role flowers and seeds play in identifying species.
 
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