I sent several people seedlings of D. madagascariensis last year.
These were grown from seed bank seeds. I've heard Gordon isn't too
sure about the validity of the name. They were supposedly collected from
Transvaal, S. Africa.
My plants are near maturity (1 year old) but they aren't caulescent
(forming a vertical stem) like the many photos I've seen of this
species. It resembles D. collinsiae although there are differences.
There's a hypothesis that D. collinsiae is a fertile hybrid between D.
madagascariensis and D. burkeana. Here's the differences between my D.
madagascariensis and my D. collinsiae.
D. madagascariensis D. collinsiae
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leaf | 4-5 cm. long. erect | 3-3.5 cm. long, angle
(petiole + | (90 degrees) when new, | 45 degrees on most
lamina) | 45 degrees when old | leaves. Usually a
| (usually the 2 newest | rosette of live leaves
| leaves are at 90 | flat on soil.
| degrees). Only dead leaves |
are flat on soil. |
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petiole | 1mm wide. | 1mm. wide.
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lamina | 1.3 to 2 cm. long, about 2/5 | 1 cm. long.
(glandular | of total leaf length. | About 1/3 of total leaf
part of leaf) | spatulate with widest part | length. Ovate to
| toward tip. | triangular with widest
| 1mm at base, 5mm at widest | part toward tip.
| point | 6-7mm at widest point.
| |
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flowers | 3-6 flowers, widely spaced | 8-12 flowers, closely
and peduncle | dark lavendar petals, | spaced, dark lavendar
| thin peduncle to 20 cm. with | petals.
| minute glandular hairs. | Thick peduncle about
| | 11 cm. with coarse
| | (non-glandular?) hairs.
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seeds | definitely linear or spindle- | between linear and
| shaped (like a "-") | pear-shaped
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Some qualifications:
Observations of D. madagascariensis based on 12 plants potted together
in an 8-inch pot of peat moss + perlite. Grown in full sun outdoors the
first year, brought inside and grown under flourescent lights last October.
Light levels were low when flowering.
Observations of D. collinsiae based on a few plants potted together in a
5-inch pot of peat moss + perlite. Grown under same conditions as
D. madagascariensis.