Cryptocoryne edithiae de Wit

In 1978, Edith Korthaus collected an unknown Cryptocoryne in Central Kalimantan. When the plant was flowered by Friedrich Möhlmann in Germany, it turned out to be a new species. The plant disappeared very soon from cultivation due to insufficient cultivation techniques. In the past decade, three more collections of plants were made in Kalimantan by Yuji Sasaki and Hiroyuki Kishi which should be regarded as C. edithiae. The spathe of the plant is characterized by a rough brown-purple limb and a yellow throat with many fine red dots, slightly different in the four accessions. In its appearance the plant is related to C. cordata var. grabowskii, a very common Cryptocoryne in Kalimantan. Three accessions of  C. edithiae show rather defect pollen and there are no fruits known, what may indicate that C. edithiae is of hybrid origin. The fourth accession (I-SAKK1) is not in cultivation. The chromosome numbers for the plants however differ: Korthaus' plant had 2n = 68 (Arends et al 1982), the two others have 2n = 51 (Jacobsen unpublished), the fourth is unknown till now. C. edithiae can best be interpreted as a complex of hybrids where different parents may be involved, to be compared with C. ´purpurea nothovar. borneoensis. In Copenhagen DNA analysis is underway (Jacobsen priv. comm.).

Click on the picture to get the full image (ca 50 k)

Sterile plants collected in 1978 by Edith Korthaus 'four boat hours' North of Sampit. The plant grows in a 'black water' stream, with a pH of about 4.
coll. Korthaus s.n.
photo Korthaus
Spathe of C. edithiae. The purple limb is rather rough (compared for example to C. cordata). There is a more or less pronounced collar, and there are fine red dots in the throat.
coll. Korthaus s.n., cult. Möhlmann M 52
photo Möhlmann
Herbarium sheet of Möhlmann's cultivated C. edithiae. Sheet size ca. 20 x 30 cm.
coll. Korthaus s.n., cult. Möhlmann M 52
photo Jacobsen
Detail of of the herbarium sheet. Note the fine red dots in the throat.
coll. Korthaus s.n., cult. Möhlmann M 52
photo Jacobsen
       
Flowering C. edithiae near Kotawaringin, West Kalimantan. Note the slight bullate leaves. In (my) cultivation the leaves remain bullate and may become brownish with a reddish lower side.
coll. Sasaki I-KOTT
photo Sasaki
Habitat near Kotawaringin.Sasaki mentions water parameters of pH = 5.0 and a TDS of 6 ppm.
coll. Sasaki I-KOTT
photo Sasaki
The limb of the I-KOTT spathe often has one or two furrows.
coll. Sasaki I-KOTT, cult. B 960
The kettle is rather short in I-KOTT. The inside wall may be reddish but is often white with only a few red dots near the male flowers. The appendix varies from white with a few purple spots to purple.
coll. Sasaki I-KOTT, cult. B 960
       
Flowering C. edithiae near Sukamara.
coll. Kishi TB06-1
photo Kishi
The lower side of the leaves are deep purple.
coll. Kishi TB06-1
photo Kishi
In (my) cultivation the leaves are bright green with a pale green lower side. Hardly bullate leaves.
coll. Kishi TB06-1, cult. B 1156
The red spots in the throat are distinct bigger than in the I-KOTT plant.
coll. Kishi TB06-1, cult. B 1156
       
Often the spots are not uniform spread in Kishi's plant.
coll. Kishi TB06-1, cult. B 1156
Small regular distributed dots in Sasaki's I-KOTT plant.
coll. Sasaki I-KOTT, cult. B 960
Kishi's plant has a slight longer kettle with only a few red dots in the top.
coll. Kishi TB06-1, cult. B 1156
Close up of the top of the spadix.
coll. Kishi TB06-1, cult. B 1156
       
Another collection by Sasaki of what is also regarded as C. edithiae, with a more pronounced collar. Water parameters pH = 4.9 and a TDS of 4 ppm. Not in cultivation.
coll. Sasaki I-SAKK1
photo Sasaki
No doubt strong related plants:
left C. ´purpurea nothovar. borneoensis, right C. edithiae.
coll. Idei B-02 & Kishi TB06-1, cult. Jacobsen
photo Jacobsen

Habitus of C. edithiae (de Wit 1990) drawn after the Korthaus plant.
drawing Y.F. Tan

Distribution of C. edithiae in Southern Kalimantan (Indonesia). The plants grow in the peat swamp forest.
       

The South of Kalimantan is to date one of the most intriguing parts of Asia in respect to Cryptocoryne. It proves to be very difficult to set taxonomic boundaries between all new collected plants, for it seems that there is an almost continuous variation in characters in species like C. cordata var. zonata, C. cordata var. grabowskii, C. ´purpurea nothovar. borneoensis and C. edithiae.

Cultivation finally turned out to be extremely easy. One to two year old leaves of the in W. Europe common beech tree (Fagus sylvatica) are soaked in water (rain / reversed osmose) for a few weeks, cleaned and drained and soaked again for a few weeks. The plants are loosely stuck in a 3-5 cm thick layer of these more or less floating, slowly decaying leaves. Water parameters soon become around a pH of 3.5, and an EC of 50 muS/cm. Fertilizing after some months is simply done by adding some new Fagus leaves. It will take a year before the plants are firmly growing but afterwards one must take care that the container does not become overcrowded because of competition for nutriments. The same competition makes it inappropriate to have more than one species in one container. Probably only one species will survive.

Updated May 2008

Literature

Arends, J.C., Bastmeijer, J.D. & Jacobsen, N., 1982. Chromosome numbers and taxonomy in Cryptocoryne (Araceae).II. Nord.J.Bot. 2 : 453-463.
Bogner, J., 1984. Cryptocoryne edithiae De Wit. Das Aquarium 185 : 564-566.
Bogner, J., 1985. Cryptocoryne edithiae De Wit. Aqua-Planta 4-85 : 17-19.
Eggers, G., 1987. Edith Korthaus. Aqua-Planta 2-87 : 74.
Graaf, A.de, 1983. Sadilek over vindplaatsen van Cryptocorynen. Het Aquarium 53(2) : 51-53.
Jacobsen, N., 1985. The Cryptocoryne (Araceae) of Borneo. Nord.J.Bot. 5 : 31-50.
Korthaus, E., 1980. Beobachtungen an Cryptocorynen auf Borneo. Das Aquarium 133 : 342-343.
Möhlmann, F., 1978. Eine rätselhafte Cryptocoryne von Borneo. Das Aquarium 12/7 : 397-400.
Sasaki, Y.,  Minima Vol.3, 2003. Pisces Publishers Co Ltd, Japan.
Wit, H.C.D.de, 1990. Aquarienpflanzen, 2. Auflage. Ulmer, Stuttgart. ISBN 3-8001-7185-6.