glow worm larvae

Description:

Larvae # Larva Have pale spots at the rear edge of each segment # Are not very bright, and usually only glow for a few seconds at a time from two small points on the rear underside of their tail segments # Often move around slowly in search of prey, using their tail segments to help themselves along a bit like a caterpillar. # Can sometimes be seen on paths in daylight, particularly in spring Adults Glowing spots # Glow brightly and continuously from large areas on the final two segments with smaller spots on the final segment (only females glow – see picture at right). Insect rarely seen by day # The adult female has a completely matte black back with just a thin paler line down its center # Usually remain in one spot either on the ground or clinging to a stem, curled so as to turn the glow upwards. Often move their tail segments from side to side. # The adult male has black wings.

Habitat:

Glow worms are found inhabiting dense woodland and caves around the world

Notes:

The family Phengodidae are uncommonly encountered beetles that have bioluminescent females that appear to be larvaiform (or larger versions of the immature stage.) These adult females are able to produce light from paired photic organs located on each body segment (one glowing spot on each side) and sometimes also from luminous bands that extend across the dorsal surface of the body between each body segment. Females appear to be more commonly encountered than larvae. Because these glowing spots along the females body resemble the windows of train cars internally illuminated in the night, they are often referred to as "railroad-worms."