Mention should probably be made of Hemileuca minette, a very obscure species or variant form that was found and named near Mexico City/ Nobody has much to say about Minette. Someone probably thought the moth was pretty and named it after a friend or relative, not even thinking that, hello, the thing was a Hemileuca. The curtain of charity seems to have been drawn.
Then there's mojavensis, now usually considered a subspecies of electra.
Hemileuca dukinfieldi was found in Brazil and described as an aberrant Hemileuca. Very aberrant. Naturalists soon concluded that it wasn't even a silk moth and apparently still disagree about what kind of moth it is, but nobody thinks it's a Hemileuca.
Photo of Hemileuca neumoegeni by U_Phantasticus.
This brings us to H. neumoegeni, which was named by Henry Edwards in 1881. By that time the ancient goddesses' names were taken, so Edwards named this "'remarkable" and "charming" moth in honor of Berthold Neumoegen, 1845-1885. His name can be written either with the "oe" or with an umlaut over the "o" in the middle syllable. Some pretty butterflies were named after Neumoegen, as well as Neumoegen's Buck Moth. When not chasing butterflies he was lucky on the stock market; he created several jobs, including jobs for field research assistants. Edwards' description of the moth refers to "Doll," which was the family name of an illustrator Neumoegen made famous. Edwards seems to have been hoping that Neumoegen would make him famous, too...and H. neumoegeni did.
Unlike the really giant-sized silk moths, the Hemileucas seldom hold their wings spread out like butterflies. They like to fold their wings as smaller moths do. Here Robynslater induces one to hold its wings mostly out to the sides, as the Geometrids do. Often they fold their wings like Noctuids.
Unlike most Hemileucas, neumoegeni usually fly at night and are often attracted to light. Sometimes they bed down for the day near street and house lights, in which case they may be run over by cars during the day. They fly between August and October. Because moths are guided by instinct rather than reason, neumoegeni are not active at the same time of day when burnsi is--and this is probably enough to keep these very similar-looking moths from hybridizing. They never meet.
H. neumoegeni is found in California, Arizona, Colorado, and sometimes Utah and Nevada.
Among the plants the caterpillars can eat is sumac. It can eat pinon and juniper needles and other desert "scrub," and although they seem unlikely to be part of its natural diet this caterpillar also loves fruit and nut trees. It can be quite a serious nuisance. If legal permission to spray insecticides on "organically grown" food crops is not withdrawn, these large, venomous caterpillars have the potential to become a real plague. For, as all farmers should know by now, the more "pesticides" you spray this year, the more pests you will have next year.
Only one species of sumac oozes urushiol enough that it's usually considered "poison," though people can be allergic to the others. Some sumac bushes are even edible; sumac berries have a pleasant sweet-sour taste like rose hips or lemon rind and are used as a spice. The species that most attracts H. neumoegeni is Rhus trilobata, the kind with "three leaflets on each leaf," just like poison ivy. It releases an odor some call a "fragrance," and some compare to a skunk, when crushed. Despite the odor and the ominous look, into the early twentieth century people ate the berries, chewed the resin, made baskets from the twigs and dyes from the plants, and some indigenous people smoked the dried leaves. It was sometimes called squawbush, skunkbush, or oakbush.
The larger silk moths, including Cecropias, Citheronias, Cynthias, and Lunas, are found in Californa and may also eat sumac. They can be almost twice the size of Hemileuca neumoegeni. Fortunately, although these caterpillars can be bristly at some stages of their lives, and can certainly chomp, they are not venomous. At least two species in the genus Saturnia, which are smaller than the giants and bigger than the Hemileucas, will also eat sumac. Of the two, S. walterorum caterpillars are also venomous, and none of the online science pages ventures to say whether S.. mendocino caterpillars are or are not.
In California neumoegeni are known to eat two native plants, a species of sumac and the "desert almond." They may find cherry, plum, almond, and rose leaves acceptable alternatives. They are not the most common nuisance species of Hemileuca in California, but nature has prepared all the Hemileucas to be a considerable nuisance wherever they go.
H. neumoegeni looks very similar to H. burnsi, and shares enough DNA with it that some would argue that they are variations within one species. Adult moths are distinguished by body color (burnsi has mostly black fur on the body, rather than red and white) and the spots on the fore wings (burnsi has round dots, neumoegeni has crescents). Photos for comparison are shown at
Photo by Tiwane, who notes that he thought the moth was decapitated. It's typical for a Hemileuca to have a small flat head out of proportion to the big furry thorax. They hardly have faces--no nose, no mouth, small eyes that are often well hidden, and females' antennae aren't very showy either--but they do have heads; small, well-hidden ones.
Photo by Hoboannie, showing what H. neumoegeni has in the way of a face.
When Tiwane touched the moth he photographed, he said, she lay on her side, curled up, as if dead, in that regressive and counterproductive defense move the whole genus seem to share. Curling up with their bristles out protects them, and causes pain to innocent people on whom they happen to land, while they are caterpillars. Once they're moths it only makes them easier for birds or mice to eat. Anyway, the moth revived and laid eggs.
Photo by ERand. H. neumoegeni usually lay 15 to 30 eggs in a clump, then rest and lay more eggs somewhere else. The size of Hemileuca egg clusters correlates with the size of the food plant; tree-feeding moths instinctively lay more eggs in one place than moths who lay eggs on smaller plants.
Photo by ERand. As in other Hemileuca species, eggs are laid in clusters and, for about the first half of their caterpillar lives, the caterpillars try to stay in clusters. Each one's bristles protect it from its siblings' bristles so they seem to enjoy feeling surrounded by their siblings in a big mass of bristles no large predator would want to bite into.
In 1984 Paul Tuskes wrote the first description of the caterpillars of this species, or type, of Hemileuca. Basically, hatchlngs are black with stiff unbranched black hairs. The second and third caterpillar skins are black with black branched spines. In the fourth instar a pale wavy line extends along either side. In the fifth instar they can be described as basically gray with elaborate camouflage patterns; spines are black with white branches, and some grow in rosette shapes on the back. Tuskes thought there might be some variation in the venomousness of different species, but did not experiment. Basically rosette-shaped bristles deliver more venom if touched, but the long branching spines on the Hemileucas reduce the chance of their being touched relative to species like Automeris io, which have short venomous spines, in rosettes or single spikes, all over.
According to Evra at Insectnet, at this early age the caterpillars don't have venom; they become real stingingworms only in their third caterpillar skin. They will curl up and drop down if the branch on which they are feeding is jiggled, though. Any kind of short hairs can raise a rash if they get down the back of your neck on a hot day. That's why barbers tape capes around people's necks.
Photo by Cakwildlife. Hemileuca caterpillars are very variable but Paul Tuskes found some consistent patterns. For Hemileucas generally, branching bristles are the family's distinguishing feature. For H. neumoegeni the smaller bristles on the lower sides are brown, and the prolegs, the little fat stumpy legs that will disappear when the caterpillar becomes a moth, are red. If the bristles on the back form rosette shapes, the lower part of each bristle in each rosette is brown.
Caterpillars hatch in April to May and usually pupate in June. When pupating they make some attempt to surround themselves with a single layer of silk to keep the sand off, but for silk moths the Hemileucas produce remarkably little silk, and the gesture toward a cocoon collapses at a touch. Where these caterpillars live, they don't need much protection from the weather, and trust a very little cover to protect them from predators.
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