The spherical eggs (0.75mm in diameter) are usually deposited directly onto the cave wall.
Upon hatching, the cylindrical larva immediately begins to glow.
When they first emerge they are usually between 3 and 5 millimeters long, and will grow to between 30 and 40mm across several months.
The larva may move around on the surface of the cave or bank before selecting a site to begin producing its silk nest.
Most larvae emerge during the spring.

The larva spins a nest out of silk on the ceiling of the cave and then hangs down up to 30 silk threads along which it regularly places small sticky droplets.
Their prey largely include other small Diptera (especially midges) although glowworm living on banks may also trap spiders and other non-flying invertebrates.
When prey is entangled in a snare, the larva pulls it up by ingesting the snare and starts feeding on the prey alive.

After five larval instars, the larva will suspend itself on a long thread and pupates over up to 24 hours.
The pupal phase lasts about two weeks.
During this time, the pupa continue to glow although males eventually lose their glow.
The adults which eventually emerge are poor fliers.
Adults usually emerge during the winter and tend to live for up to 76 hours in the case of females and up to 96 hours in the case of males.
 Females usually lay over 100 eggs and eggs usually hatch after about 20 days.

Sources of mortality for glowworms include predation by cave harvestmen (including the short-legged harvestmen, Hendea myersi cavernicola, and the long-legged harvestmen, Megalopsalis tumida), parasitic fungi (Tolypocladium sp.),
and possibly cannibalism when adults become entangled in other larvae's silk threads although evidence is mixed.
The spherical eggs (0.75mm in diameter) are usually deposited directly onto the cave wall. Upon hatching, the cylindrical larva immediately begins to glow. When they first emerge they are usually between 3 and 5 millimeters long, and will grow to between 30 and 40mm across several months. The larva may move around on the surface of the cave or bank before selecting a site to begin producing its silk nest. Most larvae emerge during the spring.
The larva spins a nest out of silk on the ceiling of the cave and then hangs down up to 30 silk threads along which it regularly places small sticky droplets. Their prey largely include other small Diptera (especially midges) although glowworm living on banks may also trap spiders and other non-flying invertebrates. When prey is entangled in a snare, the larva pulls it up by ingesting the snare and starts feeding on the prey alive.
After five larval instars, the larva will suspend itself on a long thread and pupates over up to 24 hours. The pupal phase lasts about two weeks. During this time, the pupa continue to glow although males eventually lose their glow. The adults which eventually emerge are poor fliers. Adults usually emerge during the winter and tend to live for up to 76 hours in the case of females and up to 96 hours in the case of males.  Females usually lay over 100 eggs and eggs usually hatch after about 20 days.
Sources of mortality for glowworms include predation by cave harvestmen (including the short-legged harvestmen, Hendea myersi cavernicola, and the long-legged harvestmen, Megalopsalis tumida), parasitic fungi (Tolypocladium sp.), and possibly cannibalism when adults become entangled in other larvae's silk threads although evidence is mixed.
Arachnocampa luminosa