The insect-trapping rim of Nepenthes pitchers: surface structure and function

Plant Signal Behav. 2009 Nov;4(11):1019-23. doi: 10.4161/psb.4.11.9664. Epub 2009 Nov 25.


Carnivorous pitcher plants of the genus Nepenthes capture prey with a pitfall trap that relies on a micro-structured, slippery surface. The upper pitcher rim (peristome) is fully wettable and causes insects to slip by aquaplaning on a thin water film. The high wettability of the peristome is probably achieved by a combination of hydrophilic surface chemistry, surface roughness and the presence of hygroscopic nectar. Insect foot attachment could be prevented by the delayed drainage of the thin water film between the adhesive pad and the surface. Drainage should be faster for insects with a hairy adhesive system; however, they slip equally on the wet peristome. Therefore the stability of the water film against dewetting appears to be the key factor for aquaplaning. New experimental techniques may help to clarify the detailed function of the pitcher plant peristome and to explore its potential for biomimetic applications.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Insecta
  • Magnoliopsida / anatomy & histology*
  • Magnoliopsida / physiology
  • Plant Nectar
  • Plant Physiological Phenomena*
  • Plant Structures*
  • Water


  • Plant Nectar
  • Water