Cryptocoryne crispatula Engler var. decus-mekongensis T. Idei, J.D. Bastmeijer & N. Jacobsen
From 2006 to 2010, Takashige Idei investigated the Mekong river for Cryptocoryne in Thailand, Laos and Cambodia. The results are very impressive. In Aqua Planta 35(4) two new plants are presented. More articles will come in the future. The habitat is the same as for C. mekongensis, at some places they grow together, also with var. crispatula.
The name of this new variety decus-mekongensis means 'beauty of the Mekong'. And it is!
Click on the picture to get the full image (ca 50 k)
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| Low water in the Champasak province of Laos in January. photo Idei |
When the water falls, C. crispatula var. decus-mekongensis starts growing. |
Firmly attached between boulders, in cracks. coll. Idei LK5128 photo Idei |
The leaves vary from red to green, mostly fine undulated. coll. Idei LK5128 photo Idei |
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| Also the rapids have low water now. photo Idei |
In the wet season this is all covered with turbulent water. coll. Idei LK5128 photo Idei |
Patches are well hidden between the boulders. coll. Idei LK5128 photo Idei |
The plant flowers with a typical limb, sometimes bend to the ground. coll. Idei LK5128 photo Idei |
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| Pools with stagnant water. coll. Idei LK5507 photo Idei |
Scattered over the area are clusters with this Cryptocoryne. coll. Idei LK5507 photo Idei |
The water level may rise more than 1 m in the wet season. coll. Idei LK5502 photo Idei |
The roots are firmly anchored in the crack or between the boulders. coll. Idei LK5128 photo Idei |
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| In cultivation the plants maintain their seasonal character: it thrives new leaves off November. coll. Idei LK5507, cult. B1226 photo Bastmeijer |
The limb of the spathe is smooth with irregular red-brown spots. coll. Idei LK5507, cult. B1226 photo Bastmeijer |
A longitudinal section of the spathe. There is no collar. coll. Idei LK5507, cult. B1226 photo Bastmeijer |
The opened kettle with a pronounced 'roof' over the spadix. coll. Idei LK5507, cult. B1226 photo Bastmeijer |
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| Variation in spathe size and form of C. crispatula var. decus-mekongensis. coll. Idei LK5128 photo Idei |
A just opened fruit, the five parts showing the seeds. coll. Idei LK-F5128 photo Idei |
The white part was grown subterranean. In cultivation this is less pronounced. coll. Idei LK5130 photo Idei |
C. crispatula var. decus-mekongensis is up to now only found in the Champasak province of Laos. |
Cultivation of C. crispatula var. decus-mekongensis is easy in loamy sand with or without some peat litter, but it may take an extra year to flower it. In July the plant starts withering, all the leaves will go down in this resting phase and a few spike like leaves develop (in nature it will be submerged). Only in September / October it will thrive again normal leaves. Because of its seasonal character it is not suited for the aquarium.
Jan D. Bastmeijer, December 2010
Literature:
Idei, T., J.D. Bastmeijer & N. Jacobsen, 2010. Geschichten vom Mekong: Zwei neue Cryptocorynen (Araceae). Aqua-Planta 35(4): 139-146 (see the Document service, included an English translation)
Mekong River Commission (for water heights and predictions) at: http://ffw.mrcmekong.org/