PHIL CAMPBELL — Susie Crowell does not like to be alone in the canyon after dark, not even at its mouth or inside the cozy Country Store gift shop.

After dark, the imaginative can hear the whispers of long-dead bandits who hid in the canyon’s caves or the tears of the Chickasaw Indians held captive within its natural boundaries.

Crowell, who manages the store and sells tickets to visitors wanting to tour Dismals Canyon, prefers the company of others at night, when her husband Royce arrives to take the brave into the canyon to see something, perhaps, more rare than the canyon’s ghosts.

By the glow of flashlights, visitors descend along wooden steps into the canyon. Crossing a swinging bridge, they enter a dark, cave-like area where outlaws once hid and turn off the lights.

Soon, the crevice is illuminated by another light, the glow of dozens of miniscule creatures that live on the boulder walls.

Although the creatures known locally as Dismalites are “close cousins” of rare glowworms found in Australia and New Zealand, they are actually fly larvae, said Auburn University entomologist Gary Mullen, who has studied the insects.

“It’s a very unusual group of flies, very closely related to fungus gnats,” Mullen said. Fungus gnats are found near mold and the glowing insects are thought to be so plentiful in Dismals Canyon because of the abundance of moisture and dark areas.

“The steep, well-shaded rock faces and very humid cave-like setting with a lot of algae offers a place where they can concentrate their numbers,” he said. “It’s an extraordinarily large concentration of flies.”

Although the insects were initially believed to be the only ones in North America, Mullen said since classifying them (they are classified as Orfelia Fultoni; family name, Keroplatidae), he has seen a few others in southern states, just not typically in large groups.

What makes the Dismals population so unusual is the large number of them, he said. On nights when conditions are right the steep rock face looks like a star-filled sky. Best viewing times are May through September, Crowell says, although they are seen in smaller numbers year ’round.

The light comes from a chemical reaction in two pairs of light-producing structures, one in the thorax and one near the tail end, Mullen said.

“The light is produced biologically, similar in principal to what fireflies produce,” he said. “They produce a chemical reaction, mixing compounds to create a steady glowing light or a flash. Most are a steady glow.”

The insects use the light to attract tiny flying insects into a web-like substance.

“They trap them in a sticky substance, strands of mucilage,” Mullen said. “Not really silk but the same idea, like a spider’s web.”

Mullen, whose students raised the larvae to adulthood to determine how to classify them, said it’s unlikely people would see the larvae outside of Dismals Canyon.

“You’d have to look for them very carefully. There’d only be one or a few,” he said. “They go almost completely unnoticed in the wet areas along streams. Unless you’re out there in dead of night, you wouldn’t see them.”

Dismalite tours are conducted Friday and Saturday nights, with times depending on when night falls. Call (205) 993-4559 or visit www.dismalscanyon.com for information.