DISTRIBUTION:

The Achemon Sphinx, Eumorpha achemon (Wing span: 3 5/16 - 3 3/4 inches (8.7 - 9.6 cm)), flies from Maine west to North Dakota (into Manitoba) and southern Oregon; south to south Florida, southern California and Mexico wherever larval hosts can be found.

Those who first published descriptions and assigned scientific names to many insects, simply chose names of biblical or mythological origin without any real descriptive qualities. Their purpose was simply to set a standard for purposes of identification by assigned name. On some occasions, names, mostly of Latin or Greek origin, were chosen to signify a particular character of the genus or of an individual species.

The genus name "Eumorpha" means well-formed.

In Greek mythology, Achemon and his brother Basalas were two Cercopes who were constantly arguing. One day they insulted Hercules, who tied them by their feet to his club and marched off with them like a brace of hares.

The pronunciation of scientific names is troublesome for many. The "suggestion" at the top of the page is merely a suggestion. It is based on commonly accepted English pronunciation of Greek names and/or some fairly well accepted "rules" for latinized scientific names.

The suggested pronunciations, on this page and on other pages, are primarily put forward to assist those who hear with internal ears as they read.

There are many collectors from different countries whose intonations and accents would be different.

FLIGHT TIMES AND PREFERRED FOOD PLANTS:

Eumorpha achemon adults are on the wing from June-August in the north as a single brood. There are two flights, from May-August, in the south. The larva below, courtesy of David Bygott, was found in April on a grape vine in Tucson, Arizona. The adult moth eclosed in the same month. I suspect there are flights as early as late February-early March in the more southerly states, with the possibility of multiple broods.

Adults nectar from flowers of Japanese honeysuckle (Lonicera japonica), petunia (Petunia hybrida), mock orange (Philadelphus coronarius), and phlox (Phlox).

Eumorpha achemon larvae feed upon Grape (Vitis), Virginia Creeper (Parthenocissus quinquefolia) and other vines and ivies (Ampelopsis).

Larvae get quite large and occur in both a light (green) form and a darker (tan/brown) form. The dark form, courtesy of Chris Conlan is depicted below.

ECLOSION, SCENTING AND MATING:

Pupae wiggle to surface just prior to eclosion. Females call at night, and males fly into the wind to pick up and track the pheromone plume.

Eumorpha achemon female, Louisiana, courtesy of Vernon A. Brou.

EGGS, LARVAE AND PUPAE:

Females oviposit on upper surfaces of older leaves during their ovipositing flights at night.

Eggs hatch in six to nine days, depending upon temperature and humidity.

Eumorpha achemon, third or fourth instar larva, June 25, 2005
Lake Elsinore in Riverside County, courtesy of Peter Sidoruk.

When the Eumorpha achemon caterpillars first hatch from almost globular dark green eggs (yellow somewhat just before hatching), the anal horn is dark and as long as the body, ending in two setae. At its base is a red brown patch extending part way onto the anal shield.

Egg incubation can be as few as six days, and eggs are deposited singly. The hatchling larvae have large pale green heads and yellow green bodies, feet and legs.

Larvae can shed skins and move into an identical looking second instar, except the heads are now in better proportion to the body (i.e., don't seem so large) and yellowish-white subdorsal lines and tiny dots are present.

In warm conditions larvae can molt again in as few as three or four days. The six-eight irregular (almost segmented) oblique lines, diagnostic of E. achemon, appear in the third instar.

The anal horn now angles away from the head instead of over the back.

Immature larvae have the characteristic horn-like tail which drops off (i.e., does not develop) after the fourth instar. Feeding lasts for three to four weeks and full grown larvae leave the host to pupate in undeground burrows. Image courtesy of Chris Conlan. During the second generation, larvae frequently become quite numerous and do considerable damage to grapevines.

Larval Food Plants

Listed below are primary food plant(s) and alternate food plants. It is hoped that this alphabetical listing followed by the common name of the foodplant will prove useful. The list is not exhaustive. Experimenting with closely related foodplants is worthwhile.

Parthenocissus quinquefolia..... Vitis Ampelopsis

Virginia creeper Grape Vines and Ivies

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