Cryptocoryne crispatula Engler

Rhizome up to 1 cm thick, occasionally irregularly thickened. Stolons sometimes with a metallic blue-gray colour. Root system sometimes with a few upright roots.

Leaves very variable, narrowly linear to lanceolate, green to brown, smooth to undulate to bullate, 10-70 cm long, and 0.2-4 cm wide (Figs. 7 E - K, 12, 16, 18, 29, 34); lamina in broader leaves mostly with conspicuous, lateral veins; margin entire to finely, irregularly denticulate (Fig. 28). In some forms, the leaves disappear during the monsoon period or become small, 2-4 cm long and terete (Fig. 27A, 35).

Spathe 10-40 cm long; kettle 1-2.5 cm long; tube 6-30 cm long, slightly to somewhat twisted; limb (1.5-) 3-8 cm long, more or less spirally twisted (Fig. 10), colour yellowish to grayish to greenish, with short to long, usually purple (sometimes black purple) markings (before anthesis occasionally reddish), sometimes the markings can cover the surface almost completely. The markings may be missing, just like the limb may be almost white-grounded with only a few faint markings.

Female flowers 4-6, with horizontal to vertical, round to ovate stigmas. Olfactory bodies more or less irregularly lobed. Male flowers 90-130.

Distribution: Eastern India, Thailand, Laos, Vietnam, and southern China (Fig. 6).

Habitat: The various ecological races are adapted to the varying water-bearings in the rivers in which they grow. Some are submerged all (or almost all) the year round while others are completely emerged during flowering (Dec.-Feb.).

The foliage of C. crispatula is extremely variable, but the species may be recognized by the mostly elongate, purple markings on the long, spirally twisted limb of the spathe.

Live material of C. crispatula collected at the Phu Khieo National Park showed a variation from the green, narrow-leaved form to the brown, bullate, broad-leaved form, the smallest leaves measuring 5 by 0.3 cm, and being smooth, the largest measuring 40 by 2 cm, being bullate (Fig. 18).

The spathes of the various forms have an overall morphological similarity, variation being found only in the form and density of the purple markings of the limb. The markings vary from more or less irregular lines to short, line like-dots (Fig. 10). Their density varies from almost completely covering the limb (Fig. 36) to nearly missing and the transition is continuous. In some forms the shape of the tube is slightly trumpet-like dilatated below the limb (Fig. 10 D - E), while in others it is more or less broadly to almost club-like dilatated from below the opening and into the opened spiral of the limb (Fig. 10 C).

It is important to note that the leaves can vary in size during the flowering season, and when studying herbarium material this should be kept in mind. This variability can be illustrated by the specimen NJ 77-38 from Phu Khieo, cultivated in Copenhagen. Fig. 27 A shows the specimen flowering in the beginning of November and Fig. 27 B shows the specimen in late December, a few days after the 14th spathe had withered. Thus, the actual development stage related polymorphism of a specimen under study, must be known before the limits of the variation can be outlined.

I would interpret C. crispatula as one species containing different ecological races, i.e. leaf-forms that are adapted to the water supply and the overall topography of the rivers in which they grow. In rivers with more constant water-bearings, and not too steep a fall, the more aquatic ones occur, viz. the long, narrow-leaved forms with undulate or bullate lamina. In rivers with a seasonal variation in the water-bearings, the more amphibious ones occur, characterized by having shorter, more or less smooth leaves. There are transitions between the various forms. In cultivation, all can grow emerged as well as submerged, but usually a given form grows better either submerged or emerged.

The ecological races of C. crispatula are widely used as aquarium plants. Their leaf-form is rather constant in cultivation and the races more or less suited for submerged growth. Ten years ago I was not very keen on a subspecific delimitation of C. crispatula. In later years I have been convinced of the need for recognition of some intraspecific taxa. As I then advocated, the variation within C. crispatula is very complex, with the plants known in cultivation at least half a dozen recognizable forms being at hand, some more readily distinguishable from the next than others. However, above I have tried at the varietal level to outline the most easily recognizable and most commonly cultivated ones. I know that some plants may only with some difficulty, unambiguously be referred to a definite variety. The number of varieties accepted is subjective, and in a number of years some alteration may have to be made, e.g. some more varieties recognized. This is not meant as an excuse for an insufficient treatment from my hand, but merely a recognition of the complexity of C. crispatula.

A number of plants with different leaf-shapes, especially forms with a more narrow leaf-blade, have appeared in the trade during the last 10 - 15 years, shipped via Bangkok. We do not know anything about their place of origin but judging from their shape it is likely that they come from central to northern Thailand.