Nepenthes goettingensis  Photographed at Botanischer Garten, Berlin (Germany)

Carnivory in plants is a relatively rare phenomenon. There are about 600 species, the majority of which belong to the Orders Caryophyllales and Lamiales (Ellison et al., 2009). Nepenthaceae (Caryophyllales) contains >100 species, making it the largest Family of pitcher plants. Nepenthes are the largest genus of pitcher plants, with its center of diversity in South-east Asia. The plants grow in substrates that are deficient in nitrogen and offset this deficiency by trapping animal prey, primarily arthropods. Nepenthes use combinations of wettable peristomes, wax layers and viscoelastic fluid to trap and retain prey (Moran and Clarke, 2010).
Nepenthes species target specific groups of prey animals, or are even evolving away from a strictly carnivorous mode of operation. Most Nepenthes are vines or subscandent shrubs in habit, attaching themselves to adjacent vegetation by the use of looped tendrils which develop from the tips of the leaf blades. The pitchers are in turn produced at the tips of the tendrils. The majority of species are terrestrial, but a small number of species grow epiphytically, primarily in montane habitats (Clarke, 2001; Juniper et al., 1989). In general, the fluid-filled pitchers are produced to trap and digest invertebrate prey (Kato et al., 1993; Adam, 1997).

Adam JH (1997) Prey spectra of Bornean Nepenthes species (Nepenthaceae) in relation to their habitat.Pertanika J Trop Agric Sci 20:121-134.
Clarke CM (2001) Nepenthes of Sumatra & Peninsular Malaysia. Kota Kinabalu: Natural History Publications.
Ellison AM, Gotelli NJ (2009) Energetics and the evolution of carnivorous plants-Darwin’s ‘most wonderful plants in the world’ J Exp Bot 60:19-42.
Juniper BE, Robins RJ, Joel D (1989) The Carnivorous Plants. London: Academic Press.
Kato M, Hotta M, Tamin R, Itino T (1993) Inter- and intra-specific variation in prey assemblages and inhabitant communities in Nepenthes pitchers in Sumatra. Trop Zool 6:11-25.
Moran JA, Clarke CM (2010) The carnivorous syndrome in Nepenthes pitcher plants. Plant Signal Behav 5: 644–648.