The Waxy Surface in Nepenthes Pitcher Plants: Variability, Adaptive Significance and Developmental Evolution

Abstract

The Nepenthes pitcher plants are represented by at least 100 species, most of which are found in South-East Asia (Cheek and Jebb, 2001). The pitchers of these carnivorous plants are epiascidate leaves that have evolved in response to habitat nutrient stress (Juniper et al., 1989). They have developed morphological and physico-chemical adaptations for attraction, capture, retention and digestion of arthropods (Darwin, 1875; Lloyd, 1942; Juniper et al., 1989) from which they derive most of their nitrogen supplies (Schultze et al., 1997; Moran et al., 2001; Ellison et al., 2003; but see Moran et al., 2003). The morphological diversity of the pitchers has for long fascinated collectors and naturalists, as well as scientists (Danser, 1928; Clarke, 1997, 2001; Cheek and Jebb, 2001) and could provide relevant information for phylogenetic analyses (Meimberg et al., 2006). The different surfaces of the pitcher present diverse textures (Adams and Smith, 1977; Owen and Lennon, 1999), which have been shown to contribute, in complementary ways, to insect fall (Bohn and Federle, 2004) and retention (Gaume et al., 2002; Gorb et al., 2004).