Boundaries
by Jack Nisbet

Jack Nisbet is the author of The Mapmaker's Eye, Sources of the River, Purple Flat Top, Singing Grass, Burning Sage and Visible Bones. His newest, The Collector, is due out in October.

The Army of Cecrops
June 2007

For anyone who grew up in the Southeast, as I did, summer nights provided a sensual overload of lightning bugs, cicada racket, and the warm velvety wings of wild silk moths. Luna moths, Io moths, the giant Polyphemus, all these magical creatures came alive on hot sticky evenings around the well house, or could be found glued motionless to big oak trees just after dawn. From the first time I ever leaned close to stroke the plump maroon body of a female Cecropia moth and caught a whiff of its musky odor, they became my favorite. My mother, always quick with a story, spun out the myth that went with its Latin name, Hyalophora cecrops.

The Greek work Cecrops translates roughly as "face with a tail," and belonged to a legendary Greek figure who sprang from the earth with the head and trunk of a human and the lower half of a serpent or fish. He became a king of Athens long ago, teaching the mortals not only reading and writing, but also the rituals of marriage and proper burial.

Zeus appointed Cecrops as the judge of a contest to determine the patron god of the city of Athens. Poseidon wanted the post, and struck a rock on Acropolis hill with his trident to produce a magical spring that flowed with salt water. Cecrops did not recognize that the salt symbolized his city's claim to sea power, and when Athena raised an olive tree from the same rocks, providing the populace with wood, oil, and food, he chose her instead.

When I moved West, I found plenty of new magical creatures to explore, but assumed that the wild silk moths remained behind in the leafy hardwood forests. It was years before a close cousin of the Cecropia moth I had known from the Carolinas appeared before me in Pend Oreille County, and forever changed the way I look at our landscape.

Lepidopterists call our wild silk moth Hyalophora euryalus, Latin words with hints of green shimmering glass, horrifying Gorgon heads, broad-winged fliers, and delicate nymphs. Most field guides refer to them as Ceanothus moths, which doesn't make a whole lot of sense outside the ceanothus chaparral of California. Since all the Cecropia silk moths share the banded body (much larger and plumper in the females), reddish color, and beige wing edges of our local species, and since Euryalus hybridizes with all its neighbors of the Hyalophora genus, resulting in wingspreads of maroon through burgundy to dusky rose, chestnut, and sorrel, and eye spots that wink with almost every conceivable expression, I like to think of them all as the children of Cecrops, springing up fully formed from the Earth.

The Cecropia moth of the far West, H. euryalus ranges the full length of the Pacific coast, where it feeds on a variety of host plants and is found in an astonishing variety of plant communities, from deserts and dry chaparral in Baja California to moist Douglas fir forests in the Inland Northwest. They all have a dark eye spot on the top outer tip of the upper wing, interior light wavy lines about a third of the way in on all four wings, and distinct white central eye spots.

The hind wing eye of H. euryalis takes the form of a distinct comma that is often elongated into a sweeping comet. This mark breaks the interior line of the hind wing, and is further emphasized when the adult perches on a tree or picnic table and droops its wings downward; on one that I saw fanned out in Pend Oreille County, the hind wing markings looked like two white turkeys with long arching necks. From a distance this strange and very distinctive mark makes the moth look like a screaming face, and might be used to startle potential predators Ð a common defense mechanism among kinds of wild silk moths.

As with most Lepidoptera, adult Cecropia moths are short-lived. Soon after the female emerges from her cocoon she releases pheromones that advertise her presence, and in the hours just before dawn males home in to mate with her. The female lays her eggs singly or in small groups on the leaves of a wide variety of host plants; in our area the most common are snowbrush, bitterbrush, and Douglas fir. They hatch in about ten days.

The spiny caterpillars are unforgettable. They work their way through several instars, growing fearsomely larger with each molt. The middle instars are a beautiful blue-green armed with nine pairs of yellow dorsal spines, the first three of these ringed in black. Two rows of blue lateral spines are tipped with white, and other white-tipped blue spines spring up from the head, the base of the legs, and around the anal region. Several species of Hyalophora caterpillars, especially the last instars, emit a camphor odor that is quite different from the musk of adult moths.

When finally mature, the larvae spins an oval earth-colored cocoon a couple of inches in length that sometimes glows with a silvery sheen. In the south the adults emerge in springtime, but the ones I have seen locally Ð including individuals in Bonner County Idaho, Pend Oreille County, and Stevens County near Kettle Falls Ð appeared in June, often after a spell of cool rain.

The range maps on various Internet sites do not show records of these Cecropia moths in the North Columbia country, but then again, such maps did not show tiger salamanders as filling out the region until several alert readers responded to a salamander column three years ago. If a large rose-colored moth with comma-shaped white eye spots interrupts a picnic or camping trip this month, please let The Monthly know.

Illustrations: Caterpillar and adult of Hyalophora euryalus. Courtesy of Miller & Hammond 2003.

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