I had some old pictures of the polyphemus moth (Antheraea polyphemus) so I was quite pleased to find a polyphemus moth caterpillar as I went to check the mail. Because caterpillars and the moth or butterfly look so completely different,I particularly enjoy having images of both forms of an insect to post. It's absolutely fascinating to look at a caterpillar and see the similarities and differences between it and its adult form.
I also enjoy it when the first person to scientifically describe an insect is creative with the naming. This polyphemus moth caterpillar find is therefore particularly satisfying. Polyphemus, of course, is a name derived from Greek mythology. It is the name of the son of mythical Greek gods Poseidon and Thoosa. Students of the classics will recall that this was the same Polyphemus that was encountered by Odysseus (or Ulysses) in Homer's Odyssey. According to the legends Polyphemus was a cyclops, a one-eyed giant. The word cyclops is often thought o mean one eye, but it actually means round eye. Which brings us back to our moth.
In nature, eyes come in handy for two reasons: to find food or to spot predators before you become food. With many, many exceptions, those looking to spot predators have generally evolved to have very wide fields of vision so they can see predators coming from any direction. This means they often have eyes on the sides of their heads so they can see to the front and both sides all at once. Predators, on the other hand, generally have forward facing eyes that let them focus directly on their next meal.
As a predator then, if you see another animal that is staring back at you with two eyes both facing in your direction, there's a good chance that you're in for a fight. Thus, predators tend not to attack such creatures. When random spots and markings on a moth or butterfly's wings look like two big eyes staring back at an overhead attacker, overhead attackers think twice and leave those butterflies or moths alone. This means that the individuals with that sort of spot arrangement survive to reproduce and pass down their genes to offspring that look like their parents. Finally, the entire species may be descendants of those individuals whose spots just happened to look like eyes enough to fool its predators into thinking the moth or butterfly was staring right back at them with evil intent. Moth predators include toads, snakes, birds, bats and many small omnivorous mammals such as skunks and raccoons.
The polyphemus moth is likely one such species. As you can see from the pictures here and in the linked slide show of photos, It has a distinct eye-spot on both the fore-wing and hind-wing. When the wings are swept back int he normal resting position, the eye-spots are staring straight up any would-be attacker. It is from these eye-spots that the polyphemus moth gets its name. Whether the discoverer named the moth after a cyclops because it had one-eye per wing, or because he knew that the word actually meant round eye and described the circular eye-spots of Antheraea polyphemus, I don't know.
Anyway, the polyphemus caterpillar shows no signs of the eye-spots that will as it undergoes metamorphosis in its cocoon. It does however, show signs that the rows of little black feet are different from the first six near its head. These first six feet, unlike the others, are pointed and brown. It is these that will become the adult moth's legs. The rest of the caterpillar's feet will be absorbed into the polyphemus moth's body in the cocoon.
Quick facts about the polyphemus moth (Antheraea polyphemus):
Diet: The caterpillar eats the leaves of many common deciduous trees such as beech, maple, birch and a number of others. Adults of this species do not eat at all.
Range: All across the United States and most of Canada.
When is it here? The polyphemus moth is here year round, overwintering in its cocoon.
Life Cycle: Adult polyphemus moths can be found from May to July in the North according to bugguide.net, however, I photographed the one shown above in mid-August. Caterpillars can be found from May until November. After that they will be in their cocoons for the winter. Since the adults don't eat at all, they exist only to mate and lay eggs. In warmer Southern states, two broods of Antheraea polyphemus may be raised each year.
Lifespan: The Polyphemus moth has a lifespan of approximately 12-13 months in the North.
Status: Common.
NOTES: The polyphemus moth caterpillar population is generally not dense enough to do any significant damage to forests or individual trees.
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| Staring into the face of the Polyphemus monster itself Polyphemus moth caterpillar (Antheraea polyphemus) Photo by Brad Sylvester. Copyright 2011. Do not copy. |
I also enjoy it when the first person to scientifically describe an insect is creative with the naming. This polyphemus moth caterpillar find is therefore particularly satisfying. Polyphemus, of course, is a name derived from Greek mythology. It is the name of the son of mythical Greek gods Poseidon and Thoosa. Students of the classics will recall that this was the same Polyphemus that was encountered by Odysseus (or Ulysses) in Homer's Odyssey. According to the legends Polyphemus was a cyclops, a one-eyed giant. The word cyclops is often thought o mean one eye, but it actually means round eye. Which brings us back to our moth.
In nature, eyes come in handy for two reasons: to find food or to spot predators before you become food. With many, many exceptions, those looking to spot predators have generally evolved to have very wide fields of vision so they can see predators coming from any direction. This means they often have eyes on the sides of their heads so they can see to the front and both sides all at once. Predators, on the other hand, generally have forward facing eyes that let them focus directly on their next meal.
As a predator then, if you see another animal that is staring back at you with two eyes both facing in your direction, there's a good chance that you're in for a fight. Thus, predators tend not to attack such creatures. When random spots and markings on a moth or butterfly's wings look like two big eyes staring back at an overhead attacker, overhead attackers think twice and leave those butterflies or moths alone. This means that the individuals with that sort of spot arrangement survive to reproduce and pass down their genes to offspring that look like their parents. Finally, the entire species may be descendants of those individuals whose spots just happened to look like eyes enough to fool its predators into thinking the moth or butterfly was staring right back at them with evil intent. Moth predators include toads, snakes, birds, bats and many small omnivorous mammals such as skunks and raccoons.
 |
| Polyphemus moth (Antheraea polyphemus) Photo by Brad Sylvester. Copyright 2009. Do not copy. |
Anyway, the polyphemus caterpillar shows no signs of the eye-spots that will as it undergoes metamorphosis in its cocoon. It does however, show signs that the rows of little black feet are different from the first six near its head. These first six feet, unlike the others, are pointed and brown. It is these that will become the adult moth's legs. The rest of the caterpillar's feet will be absorbed into the polyphemus moth's body in the cocoon.
Quick facts about the polyphemus moth (Antheraea polyphemus):
Diet: The caterpillar eats the leaves of many common deciduous trees such as beech, maple, birch and a number of others. Adults of this species do not eat at all.
Range: All across the United States and most of Canada.
When is it here? The polyphemus moth is here year round, overwintering in its cocoon.
Life Cycle: Adult polyphemus moths can be found from May to July in the North according to bugguide.net, however, I photographed the one shown above in mid-August. Caterpillars can be found from May until November. After that they will be in their cocoons for the winter. Since the adults don't eat at all, they exist only to mate and lay eggs. In warmer Southern states, two broods of Antheraea polyphemus may be raised each year.
Lifespan: The Polyphemus moth has a lifespan of approximately 12-13 months in the North.
Status: Common.
NOTES: The polyphemus moth caterpillar population is generally not dense enough to do any significant damage to forests or individual trees.
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