Oxygen–fauna relationships in the pitcher plant Sarracenia purpurea L. with reference to the chironomid Metriocnemus knabi Coq.

The aquatic habitat contained within the leaf of the pitcher plant Sarracenia purpurea has a dissolved oxygen concentration consistently in excess of 77% saturation in spite of a high community respiration rate. The oxygen concentration is maintained primarily by diffusion through the wall of the sarcophagus and is not affected by plant photosynthesis. Because of the consistently high oxygen concentrations, the inquiline Metriocnemus knabi is not tolerant of lowered oxygen concentrations as it is adapted to a habitat with a consistently high oxygen concentration.