A scanning electron microscopical study of hydrated and desiccated submerged leaves of the aquatic resurrection plant Chamaegigas intrepidus

Summary This paper presents a scanning electron microscopical study of the contractible submerged leaves of the resurrection plant Chamaegigas intrepidus . The submerged leaves contain xylem elements with thin longitudinal cell walls but broad spiral strengthenings. The transverse walls of these elements have very small lumina. Water transport does not seem to be their primary function. During their desiccation, submerged leaves of the poikilohydric plant Chamaegigas shrink by 75–80%, whereas leaves of homoiohydric plants shrink by 15–20% only. The shrinking process in the leaves of Chamaegigas is mainly due to contractible xylem elements which are shown to contract like an accordion. Maximum shrinkage is restricted to living leaves