Cryptocoryne x willisii is a group name comprising many different varieties of Cryptocoryne which are presumably hybrids of Cryptocoryne parva and related species (C. walkeri, C. beckettii) occuring in nature. They are distributed in the area around Kandy city in the central highlands of Sri Lanka, where they grow on river banks. Their leaves are oblong-ovate to narrow-lanceolate, with an even, unpatterned medium green colour, which resemble those of Cryptocoryne parva but grow bigger (emersed to 25, submersed to 20 cm in height). The blade of the spathe (the pseudopetal) is rough to tuberculate and is quite variably coloured, often dark purple or reddish brown.
The plant described as Cryptocoryne lucens by H.C.D. De Wit in 1962 is one variety from the C. x willisii hybrid complex that is quite commonly found in the hobby. It has long been known as robust, relatively small-staying aquarium plant. The submersed form of this Cryptocoryne has very narrow, lanceolate leaf blades and differs thus from the plant a long time erroneously known as "Cryptocoryne nevillii" with its oblong, ovate to lanceolate leaves. Please see Cryptocoryne x willisii “nevillii”.
The leaf margin of C. x willisii "lucens" may show a brownish colour and a slight undulation.
Cryptocoryne x willisii "lucens" reproduces - like other Cryptocorynes - by underground runners as well as by offshoots growing directly on the rosette, which can simply be cut off. The plant is as easy in cultivation as Cryptocoryne wendtii or C. beckettii. Compared with these relatively broad-leaved plants, often of a brownish colour, this Cryptocoryne is more similar to C. parva, the smallest Cryptocoryne, however, it grows significantly larger and a lot faster.
C. x willisii "lucens" lends itself to creating narrow-leaved, dense, medium green bushes in the fore- and middleground of aquascapes. In tanks of sufficient height, C. x willisii "lucens" can even be used as grass-like ground cover. It is a slower-growing alternative to some Helanthium species, whose runners are often too invasive.
In dense, high-grown tufts of C. x willisii "lucens" the rhizomes have been known to grow upright; then they should be trimmed back considerably.
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[widget=aquaticplants/cryptocoryne-willisii-lucens]Cryptocoryne × willisii "lucens"[/widget]