The leaves of Heliamphora are reportedly not very efficient at catching insects, judging from the quantity of insects found at the bottom of the tubular leaves ("pitchers"). The leaves of H. heterodoxa, shown here, show several distinct regions. The small hood-like "spoon" at the tip of a leaf has nectar glands on its lower surface. The reddish color of the spoon may attract insects, and the hood-like shape might prevent nectar from being washed away by rain--these are only guesses. The funnel-like zone of the leaf below the spoon tends to be reddish and therefore an insect might follow that color cue. The lower neck-like part of the funnel has downwardly-pointing hairs that insure that an insect will continue to walk downward, since walking upward against these tiny spikes would be difficult. The lower part of the leaf, a little wider than the base of the funnel, contains water with a digestive enzyme, a pool from which an insect, once caught, rarely escapes. The leaf seems like a well-designed trap. If the number of insects caught is fewer than in leaves of Darlingtonia and Sarracenia, perhaps that reflects a relatively low insect density in the relatively high elevations of the tepuis.
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