The Hickory Horned Devil Caterpillar

Last summer, a friend posted an online picture of a hickory horned devil caterpillar, a monstrous beauty of an insect I had never laid eyes on. I was stunned. I thought I knew of the most remarkable insects in our neck of the woods. Mother Nature snorted rudely at my reaction, reminding me that humans are notoriously blind to a myriad of beguiling beings that run, walk, slither, fly, live, and die beneath our noses and before our eyes. 

After hatching from its egg, an infant hickory horned devil is an inconspicuously small black shape-shifting larva that feeds at night and curls in a j-shape to sleep the day away, using leaf tops as hammocks and cleverly masquerading as a bird dropping, a persona that appeals to no predators. The larva molts four times, enlarging with each molt, for about forty summer days spent devouring shredded tree- top foliage of hickory, walnut, pecan, persimmon, sumac, or sweet gum trees. Though it eats the leaves, the amount consumed does not damage the host tree and does not warrant classification as a pest. Hidden from human eyes in the lofty branches, it completes its infancy and transforms into a caterpillar worthy of its horned devil moniker in a manner reminiscent of Bruce Banner’s mutation into the Incredible Hulk. The little larva, once mistaken for bird poop, mushrooms into the largest North American caterpillar at six inches long and with the heft of a hot dog. No relish, please.

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With each molt, the caterpillar changes colors, wearing shades of yellow, brown, and bright orange before putting on a final coat of green, similar to the Hulk’s hue, that acquires a turquoise tint as the larval stage nears its end. To unnerve grub eaters, it dons a massive reddish-orange headpiece of horns tipped with black menacing spikes. Enhancing the fear factor, two long and two shorter red spikes protrude from the next two segments, and four short black spikes occur on the abdominal segments. To increase its creepy quotient, big black spots on the body mimic omniscient eyes. Gullible caterpillar-gorging chickens shy away with a cluck, but wiser birds devour the hefty snacks like Cheetos, without fear or harm. The caterpillar’s spikes neither pierce nor sting; its bright colors, often indicative of a creature’s toxicity, are just for show; and its ruse of rearing its horned head and vibrating violently to create a buzz that sounds alarmingly like a rattlesnake’s warning is but a scam. 

The faux devils who escape hungry birds eat their last meal like condemned prisoners and descend from the host tree to the ground, where they frequently become snake fodder. Those who avoid attracting ravenous snakes burrow into soft dirt and form a small earthen cavern instead of weaving a cocoon. They are transfigured into glossy brown pupae, which will spend winter entombed like mini-mummies.

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The following summer, from the tomb arises an apparition that is the adult regal moth, a.k.a. royal walnut moth, giant cousin of the silk moth and the largest moth north of Mexico. Its tragically short nocturnal life begins at dusk when it emerges and drags its heavy orange-and-yellow-striped body up a stalk of vegetation, pumps its crumpled wings with fluid, and unfurls them. When the orange veined, greenish-gray wings dotted with creamy yellow are smoothed open, they measure up to six inches across, a literal handful. Portly females spritz pheromone-spiked eau de cologne into the evening air that wafts their messages to lusty suitors seeking partners for the brief dance of life. 

With no working mouthparts or hunger for food, the moths’ raison d’être is survival of the species. They mate on the second night of their existence as moths, and the females lay eggs the following night. All the adults live, mate, and die within a week, a tiny window of opportunity to fulfill their mission. Though the wisp of life ends for the adults, the cycle of life continues for the species. 

I have watched vigilantly through summer’s days but have seen neither spiked horn nor gossamer wing in the flesh. Despite the fact that each female moth lays about 250 eggs, the numbers are decimated by antagonistic forces of nature like parasitic flies along with hungry birds and snakes. Possibly the best time to see the caterpillars is when they depart their leafy protective bowers to reach the ground, but there is little chance of being at the base of the right tree at exactly the right time. 

Although I could order horned devils online, I refuse. I want to see the devils au naturel, which isn’t too much to ask, is it? There’s always next summer, one hopes, and the elusiveness of the insect is an essential part of the enchantment of the quest.