DISTRIBUTION:

Automeris hesselorum (wingspan: males: 58-64mm; females: 61-68mm // forewing length: males: 31-33mm; females: 34-38mm) flies in the lower mountainous regions of
northwestern Mexico (common) and into extreme southern Arizona where it is rare. Joel Szymczyk reports, "A. hesselorum ranges in the US only in a small part of southeast Arizona, from the Patagonia mountains west to the Pena Blanca area."

In his Hemilucinae 2002, Lemaire equates iris hesselorum with nominate iris. However, Brechlin & Meister, 2011, elevate hesselorum to full species status. Lemaire writes, "The loss of the submarginal band of the forewing, that was regarded by Ferguson (1972) as a characteristic of Automeris hesselorum, is usual in the topotypical of Automeris iris iris population from Oaxaca. "The same phenotype is apparently predominant on the western slopes of the Sierra Madre as far south as Nayarit." Male to right courtesy of Joel Szymczyk

Females are only slightly darker than males and will come in to lights. Joel Szymczyk reports a female at 15 Watt black light tube sheet on August 1. The antemedial line of the forewing is well-defined and the postmedial line is relatively straight and unbroken. Female Automeris hesselorum right, composited and transformed by Bill Oehlke.

The proximity of the hindwing ocellus to the post median, narrow black band is variable.

FLIGHT TIMES AND PREFERRED FOOD PLANTS:

Automeris hesselorum are on the wing from mid July into early August.

Larvae feed upon oaks (Quercus palustris), desert willow (Chilopsis), kidney wood (Eysenhardtia polystachya), mimosa and false acacia (Robinia pseudoacacia).

Automeris hesselorum male, Arizona,
courtesy of Eric van Schayck.

Automeris hesselorum male, Arizona,
courtesy of Eric van Schayck.

Automeris hesselorum female, Arizona,
courtesy of Eric van Schayck.

Automeris hesselorum female (more likely A. hesdimasiana), Sinaloa, Mexico,
courtesy of Jurgen Vanhoudt.

ECLOSION, SCENTING AND MATING:

Automeris iris hesselorum females begin calling after 1:00 am. Males, which are slightly smaller than females, use highly developed quadripectinate antennae to locate females at night by tracking her airbourne pheromone plume. The pair usually separates just before dawn.

EGGS, LARVAE, COCOONS, AND PUPAE:

Eggs are deposited inclusters of 6-40. "They are typical Automeris ova... slightly enlongated with a dark micropyle on top of each egg. These [are] fairly small, smaller than the ova of either io neomexicana or zephyria." Information and image courtesy of Joel Szymczyk "As the ova matured, they took on a darker gray color, and the micropyle of each became black."

Incubation takes about two weeks at a temperature of 75* to 80* F. "Upon hatching, the larvae [are] very small, and solid orange in color, very much like the early instar larvae of io neomexicana." Joel initially offered them Red Oak leaves, but found they would not accept them. The day after the larvae hatched and still had not eaten any oak, he supplied them with leaves of Desert Willow (Chilopsis linearis) and a local species of Locust (Robinia sp.). The larvae quickly accepted the locust. Information and second instar larval image courtesy of Joel Szymczyk. Larvae are gregarious, especially in the early instars, and are armed with urticating spines. There are six larval instars.

Larvae remain very gregarious into 3rd instar (above), where the base color has changed from orange to yellow-green. "In this instar the larvae's defenses have increased... Stinging spines typical of all Automeris cover their bodies in neat rows. They still like to stick together in groups of 10 to 15."

Automeris hesselorum 5th instar, courtesy of Joel Szymczyk.

Eggs are deposited in large clusters and larvae are highly gregarious. Urticating spines offer the Automeris hesselorum larvae much protection. Photo courtesy of Leroy Simon.

Automeris hesselorum first instars, Arizona, courtesy of Leroy Simon.

Automeris hesselorum second instars, Arizona, courtesy of Leroy Simon.

Automeris hesselorum fourth instars, Arizona, courtesy of Leroy Simon.

Automeris hesselorum fifth instar, Arizona, courtesy of Leroy Simon.

At best, larvae spin a very loose cocoon amongst leaf debris, but pupation is often just under surface litter. Image courtesy of Chris Conlan.

Automeris hesselorum, mature larva, Harshaw, Santa Cruz County, Arizona,
reared on oak, courtesy/copyright Franz and Julian Renner.

Hi-

Here are two photos I took a few minutes ago. They are both Automeris iris. The first is one moments after shedding into pupa. Only a few of these guys have made anything resembling a cocoon; most are just under some leaves with a bit of silk. A few, like this one, just made a loose silk mat to lie on.

The second photo is a pupa that is a few hours old, in a very loose cocoon. Something about that photo I like. I'm not too emotional about art... but God's handiwork can really be amazing.

Take care,

Hunter and Joel

http:www.zianet.com/jszymczyk/lepidoptera

In Latin or Greek, from whichever "pupa" derives, the translation is "ghost". Intersting to see the "body" shrouded in silk, resting, waiting for a glorious day of "resurrection!"

Automeris hesselorum (more likely A. hesdimasiana) cocoons and pupae, Sinaloa, Mexico,
courtesy of Jurgen Vanhoudt.

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Recent DNA barcoding results, as reported by Brechlin and Meister, 2011, indicate that Automeris iris hesselorum, which Lemaire treated as a synonym of A. iris iris, should be elevated as a distinct species, Automeris hesselorum, flying in Arizona: Santa Cruz; and northwestern Mexico: Sonora, Chihuahua, Sinaloa and Nyarit.

The DNA results, as interpreted by Brechlin and Meister, 2011, also indicate that those specimens from northeastern Mexico: Tamaulipas and probably Nueva Leon are another distinct species, Automeris tamaulipasiana. If I am translating Brechlin and Meister correctly, I think Automeris tamaulipasiana corresponds to the "iris form ferruginea" which is from Mexico City, so Automeris tamaulipasiana would have a range as far to the southeast as at least Mexico City.

These three moths, iris, hesselorum and tamaulipasiana, are also distinct from Automeris occidentalis (previously synonymized with iris), which is reported from Guerrero, in western Mexico.

Lemaire, in his Hemileucinae, 2002, treated all of the above as forms of iris, rather than distinct species, and Lemaire indicates that Jalisco, San Luis Potosi, Michoacan, Morelos and Distrito Federal are also home to what he considered to be nominate iris. Those locations are not necessarily vaild for iris, and could apply to occidentalis and/or tamaulipasiana.

Kelly Price sends an image from Hidlago, Mexico, of what I considered to be Automeris iris iris, before publication of DNA results and interpretations by Brechlin and Meister. I think it is more likely A. tamaulipasiana.

There seems some consistent differences in appearance between most of the four species, but it is not clear if any are sympatric or where exactly the range of one species ends and another begins.

The following plate and notes will hopefully prove useful.

Automeris hesselorum: extreme southern Arizona and northwestern Mexico, probably as far south as Nyarit; fw ground colour almost uniform mousey-grey-brown with little contrast. Hw postmedian band/arc thinner than iris, submarginal band/arc also relatively thin, uneven along outer edge. Size of hw ocellus and proximity to post median band quite variable. Automeris occidentalis: Guerrero, Mexico; male fw length: 35-36mm; Fw outer margin seems least oblique in this species, reported as light grey in Entomo Satsphingia, but I think this lighter, yellowish specimen is occidentalis. Hw postmedian band quite thin; submarginal band also relatively thin with uneven outer edge. Automeris tamaulipasiana: Tamaulipas, Mexico, probably most of eastern Mexico south to Mexico City; male fw length: 34-35mm; male fw apex not pointed; fw ground colour more even reddish-brown with less contrast between basal/median/postmedian areas. Hw ocellus smaller than in iris; much more red hairs along inner margin and reddish scaling along hw costa than in other species; post median/submarginal arcs thicker than in two species above Automeris iris: Oaxaca, Mexico; male fw length: 35-37mm; male fw apex is slightly produced and pointed; very strong contrast between dark brown fw basal area and much lighter off-white median/post median areas with much speckling of small grey-brown scales. Hw ocellus large; post median/submarginal black arcs relatively thick, even.