Aqua Planta 35,4: 134-138
A new variety of Cryptocoryne crispatula from Guangxi province of China
By Zhou Hang (China), He Heng Wei (China), and Niels Jacobsen (Denmark)

Summary
A new variety of Cryptocoryne crispatula Engler var. planifolia H. Zhou, H. W. He & N. Jacobsen, var. nov., is described and illustrated; also ecological data are given. It mainly differs from the other varieties by broader leaf blades up to 4.5 cm wide and red-brown underneath, further by a pure white limb of spathe.

In January 2010 He Heng Wei posted a series of underwater pictures of wild Tanichthys albonubes (White Cloud) from Guangxi Privince, China, on a local aquarium fish board.There were a couple shots showing a Cryptocoryne as background which he suggested to be C. kwangsiensis. However, C. kwangsiensis is synonym of C. crispatula var. balansae and the plant in the picture had a couple characteristics that were different to this and other varieties of the crispatula group: 1. Submersed leaves were smooth and broad; 2 lower surface of submersed leaves were red-brownish in color. A closer look at the original Heng Wei’s original picture, revealed a clearer image of the pure white colored spathe, and the spirally twisted limb resembled the spathe of C. crispatula in general.

A trip was quickly arranged to Dongxing City; a city located at the river mouth of Beilun river which separates Dongxing from Vietnam’s Quang Ninh province. Back in 2005, Zhou Hang recorded C. crispatula var. flaccidifolia from feeder streams as well as the Beilun main river. Upon arrival, He Heng Wei guided the tour to the locality: a small feeder stream to a river flowing into Gulf of Tonkin. The stream is well hidden from the main road and surrounded by secondary forest. The stream is 1 to 2 m wide, shaded as it is mostly covered by vegetation along the bank; and rather flat, thus the water flow was slow. The bottom is a mixture of small stones, mud and fallen leaves at the lower part of the stream, while the upper stream consists of medium sized rocks and small stones. This Cryptocoryne habitat is unlike any other kind encountered in China; indeed it looks like a typical forested stream in South East Asia.

Large submersed plants were found in the lower stream where the water level was about 1 meter deep. The water parameters were: 20.2° C; pH 6.0; KH 1.0; Fe 0.5 mg. A bigger population was found in the upper stream where the water level was only 20 - 30 cm deep. The Cryptocoryne is growing in between the rocks and some among the roots of vegetation along the bank. Most of the plants are submersed, the leaf lamina of larger plants could reach 15 to 20 cm in length and as wide as 4.5 cm. Small sized emerged plants were also found in the upper stream, and these leaves are shorter, smooth and flat. Many plants were flowering and some with fruits. Small flies were observed in the cut open kettle. Inside color of kettle is pink-red in upper part. Some specimens were sent to The Netherlands and Denmark for further study. The conclusion was that the plants in question belonged to C. crispatula, and they furthermore proved to be different from other known varieties of C. crispatula to such a degree that it would be reasonable to consider it a new variety.

Unfortunately the description of this new variety was too late to be included in the recently published volume of the Flora of China (2010), so it is described here.

Description
Cryptocoryne crispatula Engler var. planifolia H. Zhou, H. W. He & N. Jacobsen, var. nov. Folia 20-30 cm longa, lamina 1.5-4.5 lata, pleurumque submersa, flaccida, lamina supra viridia, subtus rubro-fuscida, plana, margine paulum undulata; spathae 15-30 cm longus, albus, limbus arcte tortuosa.

Type: China, Guangxi, near Dong Xing City, alt. 25 m., 30 Jan 2010, Zhou Hang and He Heng Wei s.n. (KUN, isotypes C, L, MO).

Leaves usually submerged, rather flaccid, green, lower surface red-brownish, 20-35 cm long, lamina 15–20 × 1.5–4.5 cm, smooth to slightly undulate along the margin; midrib conspicuous, lateral veins less so, emergent leaves shorter. Spathe 15-30 cm long, limb pure white with a rather long and rather regular spiral. Chromosome number: 2n = 36? Flowers from December til April. Distribution: Rivers, streams. Guangxi.

In relation to the newly published volume of the Flora of China (2010) C. crispatula var. planifolia keys out as follows:

1a. Plants with short rather stiff upright emergent leaves (0.6–2 × 10–30 cm), 
submerged leaves short, terete, 2–10 cm. 
2a. Spathe with a short, thick limb spiral, with distant to dense 
red spots .................................................................................var. yunnanensis
2b. Spathe usually with a long, thin/narrow limb spiral, with regular to irregular shorter or longer purplish to reddish 
lines (or limb pure white) ............................................................... var. crispatula 
1b. Plants with long flaccid-lax submerged leaves (0.2–4 × 20–70 cm). 
3a. Leaves 0.2–0.4 cm wide ................................................................var. tonkinensis
3b. Leaves 0.5–4.5 cm wide. 
4a. Leaves 0.5–1.2 cm wide, smooth to undulate ............................................var. flaccidifolia
4b. Leaves 1.5–4.5 cm wide, smooth to undulate to ± bullate 
5a. Leaves 1.5-4.5 cm wide, smooth to slightly undulate along the 
margin; spathe limb white ................................................................ var. planifolia
5b. Leaves 1.5–4 cm wide, ± bullate; spathe limb with purple 
markings ................................................................................. var. balansae

The main river, which is about 15 to 20 meters wide, opened and well exposed to sunlight has C. crispatula var. flaccidifolia growing in big clusters. The straight distance from C. crispatula var. flaccidifolia to C .crispatula var. planifolia at the lower part of the stream is maybe less than 20 m.

However, their distribution line is clear. Two factors: dark vs. bright; water flow fast vs. slow, are the key points separating the two. Such difference in habitat affects not only the flora but fauna as well; Tanichthys albonubes is only found in the feeder stream; another example is Macropodus hongkongensis (Hong Kong Paradise Fish) that is found in feeder stream while M. opercularis (Paradise Fish) was found in main river. Such micro habitat differences may often be overlooked, and sure more detailed field work is needed in the surrounding areas to find more populations. So far only one locality is confirmed.

The new variety, puts the variety count of C. crispatula in China to 5 (var. crispatula; var. yunnanensis; var. balansae; var. flaccidifolia and var. planifolia). The var. tonkinensis may also occur in China but is unrecorded yet. As Cryptocoryne crispatula var. planifolia occurs in nature in cooler water of about 20° C, it is suited for aquaria with cooler water.

Acknowledgements:
Dr. J. Bogner kindly translated the text from English.

References
Flora of China, vol. 23: 20-22. 2010. http://flora.huh.harvard.edu/china/mss/volume23/Flora_of_China_Vol_23_Araceae.pdf