Rapid plant movement slower "growth-movements" of plants, called tropisms. Tropisms encompass movements that lead to physical, permanent alterations of the plant while rapid plant movements are usually reversible or occur at over a shorter span of time. A variety of mechanisms are utilized by plants in order to achieve these fast movements. Extremely fast movements such as the explosive spore dispersal techniques of "Sphagnum" mosses may involve increasing internal pressure via dehydration, causing a sudden propulsion of spores up or through the rapid opening of the "flower" opening triggered by insect pollination. Fast movement can also be expressed in predatory plants, where the
Scheuchzeria species was known from, and only one where it currently occurs; it is extinct at a few other wetland sites further south in Britain, being found in pools and west hollows of ancient undisturbed Sphagnum bogs. Scheuchzeria Scheuchzeria palustris (Rannoch-rush, or pod grass), is a flowering plant in the family Scheuchzeriaceae, in which there is only one species and Scheuchzeria is the only genus. In the APG II system it is placed in the order Alismatales of the monocots. It is a herbaceous perennial plant, native to cool temperate regions of the Northern Hemisphere, where it grows in wet "Sphagnum"