During the larval stage, the glowworms create a nest, first by making a mucous tube that measures up to 16 inches (40 centimeters) long, which is where the glowing larva resides, and then by suspending a curtain of sticky threads — some as long as 20 inches (50 cm) — from it, von Byern said.
These sticky threads catch flying insects — such as moths, mayflies and sand flies — and crawling critters, including ants and millipedes, and even small land snails, von Byern said. Once the prey is trapped in the sticky silk, the glowworm hauls up the thread with its mouthparts, chows down on the meal and tidies up its nest, keeping the fishing lines clean for future prey.
In the past, researchers assumed that glowworms used oxalic acid (a chemical often found in plants such as spinach leaves) to poison their prey, but past research proved that idea wrong, von Byern said. Rather than poison their prey, the larvae trap it.