A sun pitcher plant of the genus Heliamphora. A lot of ants fall victim to the plant. Numerous smooth hairs on the internal wall all point down, making it impossible for a trapped insect to climb out again. Nevertheless some species of flies do live within the soup of water and digestive enzymes that is contained within the "pitcher".
Thanks for the extra information, Neblwald. I wonder how these flies can live. They must have evolved quite a sophisticated mechanism to protect themselves from that broth.
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