Cryptocoryne minima is well known from Penang and Kedah in West Malaysia. Plants were regularly imported into Western Europe from the 60's. See for example the catalogue from Shirley Aquatics UK (Roe 1967). In 1971 De Wit described a new species as C. zewaldiae which originates probably from West Malaysia. This plant is a bit taller than - the until that time known - C. minima. He named the plant after Ike Zewald, the artist who made the drawings at the institute in Wageningen (see the botanical link to WAG). In his book there is a picture and a drawing (de Wit 1971, 1990).
Robert A.Gasser (Florida, USA), a very good Cryptocoryne grower, got plants imported from Sumatra. There was no information on the exact locality.They were shipped together with C. scurrilis from central Sumatra. This plant flowers with a distinct yellow limb of the spathe. The margins of the limb are rather denticulate (the picture above is unique for it is the only picture of the type material). This plant is described as C. gasseri (Jacobsen 1979). This plant has also very bullated leaves, as is seen in C. amicorum. Kasselmann (1995) gives a picture of C. gasseri which lacks the denticulate margin of the limb. The origin of that plant is unknown and is probably not from Sumatra.
In 1979, Wim de Wilde and Brigitta Duyfjes collected a new Cryptocoryne in the Leuser Reserve in northern Sumatra with strongly bullated leaves. Because there wasn't an inflorescence, many growers were involved to get this plant into flower. Robert A. Gasser was the first who succeed. His plant was the basis for the description by De Wit and Jacobsen (de Wit 1983) as C. amicorum, the 'Crypt of the friends'. Soon it turned out that other plants from the same collection could have a yellowish to purple limb of the spathe. A second collection in 1991 gave the same variation, however the original red striped limb is never seen again.
The Sumatra forms are very difficult to maintain in an aquarium, there prefer rather acid conditions. The Malay forms do better. But they vary very much. Small plants may have elliptical blades and are hardly to distinguish from other species. The cordate leaves from the Sumatra forms are also seen in some forms from West Malaysia, with less bullated leaves, and this may be the best character for C. minima. The inflorescence is typical (though there is some resemblance to C. scurrilis and C. nurii). The unopened limb of the spathe stands oblique in respect to the tube. Normally the tube does not exceed a length of 1 cm but it may be up to 4 cm! The pictures above give an impression of the variation of the limb of the spathe.

Updated December 1997

Literature.

• Bastmeijer, J.D. & W.Leenen, 1983. Cryptocoryne zewaldiae. Het Aquarium 53(11) : 276-279.
• Bastmeijer, J.D., 1986. Cryptocoryne amicorum De Wit et Jacobsen. Aqua Planta 2-86 : 51-54.
• Bastmeijer, J.D., 1986. Cryptocoryne amicorum De Wit et Jacobsen. DATZ 39(10) : 471-473.
• Bastmeijer, J.D. & B.E.E.Duyfjes, 1996. Zwei Cryptocorynen aus dem Gunung-Leuser-Nationalpark (Sumatra, Indonesien), 1. Teil. Cryptocoryne minima Ridley. Aqua Planta 3-96 : 136-142 (reprint in Aqua Planta 4-96 : 191-197).
• Jacobsen, N., 1979. Cryptocoryne gasseri N.Jacobsen, sp.nov. (Araceae). Bot.Not. 132 : 144 .
• Jacobsen, N., 1982. Cryptocorynen. Alfred Kernen Verlag, Stuttgart.
• Jacobsen, N. & J.Bogner, 1986. Die Cryptocorynen der Malaiischen Halbinsel (1.Teil). Aqua Planta 4-86 : 135-139.
• Kasselmann, C., 1995. Aquarienpflanzen, Ulmer, Stuttgart.
• Ridley, H.N., 1910. New or Rare Malayan Plants V. J.Str.Br.Roy.As.Soc. 54 : 61 (the original description of C.minima).
• Ridley, H.N., 1925. Cryptocoryne. Fl. Malay Pen. 5 : 86-88.
• Roe, C.D., 1967. A manual of aquarium plants. Shirley Aquatics Ltd.
• Wit, H.C.D.de, 1971. Aquarienpflanzen. Ulmer, Stuttgart.
• Wit, H.C.D.de, 1983. Aquariumplanten, 4e druk. Hollandia, Baarn.
• Wit, H.C.D.de, 1990. Aquarienpflanzen, 2. Auflage. Ulmer, Stuttgart.