Hemileuca latifascia was quickly recognized as the same animal as H. nevadensis and/or artemis (though not by everyone--see below). H. limae was soon recognized as the same as H. burnsi. H. lintneri was soon recognized as the same as H. maia. H. lucina is similar enough to maia that some experts think they should be counted as one species, but there are slight consistent differences. Maia, the Eastern Buck Moth, is found in New England too--and on into Maine and Canada--but lucina, the New England Buck Moth, is more of a northeastern specialty, infrequently found in New York, New Jersey, Pennsylvania, or even Virginia. (Some dispute that lucina is ever found in any State other than Maine, Massachusetts, or New Hampshire.) Lucina is native to southeastern Canada, too, where some people now think it's a threatened species that they claim to believe might even be missed.
This photo by Tom Murray, taken in Boston in September, shows lucina as generally lighter in color than maia--more than "half white/" Not all individuals show as much white as this one. They are basically grey moths with the the typical Hemileuca shading across the wings. On average their wings are smaller, paler, and more transparent than maia's, but the ranges of size, color, and scale loss overlap enough that they can't really be identified by looking at them.
Photo by Fynkynd, taken in Maine in September, showing how transparent the wings of H. lucina often are. Moths' wings get their color from tiny scales. In some species, especially Hemileuca, these scales flake off easily. Note how you can see the moth's body through both layers of wing and can see the edge of the hind wing covered by the fore wing.
The wingspan is about two inches (females usually larger than males, etc.) but the Hemileucas reduce their visual size even further by folding their wings as smaller moths do. They seem generally to be going for a bird-dropping camouflage effect, though the spots on the forewings may at some angles suggest some sort of animal's eye watching a potential predator, too.
Photo by Ina82, Halifax (Massachusetts), September, showing a melanistic individual. Yes, even as Hemileucas go, lucina have extra-heavy fur capes on the thorax and over the wing joints. All the Hemileucas look furry and cuddly to some people, and yes, it's safe at least for a human to hold a moth loosely in the hands, as long as the moth isn't struggling frantically to escape. While awake these moths have a short time to do a lot of things more important to them than being fondled by humans.
Does it matter to people in Pennsylvania or Virginia whether our orchards are infested, at fruit-picking time, with maia or lucina? Only in a "Trivial Pursuit" sort of way. DNA studies suggest that the difference between maia and lucina may not qualify as a real species difference. Though science is the pursuit of objective facts that transcend differences of opinion, scientists have not reached agreement on all of those facts--for example, when they consider the baffling variety of Hemileucas, how different animals have to be to be counted as different species.A horse and a donkey belong to different species within one genus. They can share a pasture and become friends, and, if the female comes into her short breeding season without being aware of males of her own species in the neighborhood, they are likely to produce a foal together. This crossbreed foal will show different traits depending on which species each parent belonged to: the classic mule, produced by a female horse and male donkey, is generally preferred to the offspring of a female donkey and male horse. Either way, the crossbreed's distinctive traits include sterility. Though crossbreeds, such as mules, may look like a whole new species, most of them are sterile. In honor of this well-known example, biologists call all sterile crossbreeds "mules."
Hemileucas, it turns out, are not infrequently attracted to what appear to be Hemileucas of different species. What their offspring look like depends on what they eat. Sometimes crossbreeds don't know what to eat, and don't eat, and don't grow up--caterpillars are pretty dumb animals. If they do eat, they may resemble the parent who ate whatever they eat. If able to eat something different from either parent, they may resemble a whole different species, or type, of Hemileuca found in a different place. Genetic differences seem to determine their food choices; maia and lucina caterpillars can eat each other's food plants, and will usually survive, but each type seems healthier when maias eat oak leaves and lucinas eat meadowsweet. But food choices may determine the development of field marks in caterpillars and moths.
Meadowsweet grows as far south as North Carolina...but if a stingingworm eats meadowsweet in North Carolina, is it "really" H. lucina?
Well...humans. though not as variable as dogs or Hemileucas, do show a wide variety of traits. Unfortunately visible features aren't reliable predictors of whether any two humans can produce viable offspring. Some people, like Abraham and Sarah in the Bible, seem unable to have children together, although Abraham was able to have children with other women. When humans are unable to have children together, in fact, likely causes include their having a lethal gene in common--being too much alike. So obviously we don't call couples who end up adopting children members of different species, or even subspecies. They are Homo sapiens sapiens and they may have inherited the problem gene from a common ancestor.
So why do we call Hemileuca lucina and Hemileuca maia different species? Because that's the way we learned about them in grade five? Is the business of science to correct misunderstandings we all absorbed in grade five? Etc., etc., etc. Long story short: maia and lucina have very few genetic differences. Variable as maia is, it might make sense to count lucina as one of maia's more common variations. We may continue to count lucina as a separate species for a long time. We will be doing that mostly because we learned to do it that way in grade five. We learned to do it that way because Professor Reiff in 1910 argued that having different habits, and not crossbreeding, qualified animals that can look identical to be counted as distinct species.
Lucina and maia have been perceived as distinct species long enough to have been named after different goddesses. Lucina was worshipped in the city of Rome. Her full name was Juno Lucina, the Spirit of Bringing to Light. Europeans have described giving birth as "bringing a baby into the light" for a long time. However, with that name the spirit to whom prospective parents and grandparents prayed was also seen as having something to do with the moon, and if you think I think I've read enough about the history of those cults to try to explain them, you are mistaken. Suffice it to say that later Romans weren't sure whether to classify Lucina as an aspect of Juno or of Diana. These perplexing animals get their name from a myth that was, if not perplexing to those who believed it, at least told differently at different times.
"Lucina" can also be interpreted as "showing light, translucent/" All of the Hemileucas tend to lose wing scales and have translucent wings; lucina is said to be among the species that lose their wing scales most easily.
Both species, or types, are very variable. Females tend to be bigger than males, and individuals found further south tend to be bigger than those found further north, but there is enough overlap and variability to make generalizations almost useless. While feeding on meadowsweet lucina hatchlings have been described as having a shiny, polished-looking black color rather than the softer gray-black color of maia hatchlings. Monographs have been written about the differences among maia, lucina, slosseri, nevadensis, and if it comes to that some of the Southwestern species too, but even the moths themselves don't seem positive about the differences. Usually they can choose a mate of their own species, but not always. Christian Schmidt, studying Canadian Hemileucas (including latifascia), found that lucina usually seem to avoid crossbreeding with maia and presumably never meet H. artemis, but they have crossbred successfully with latifascia. This may be because lucina and latifascia are more closely related to each other than either is to other species in the general group of gray-colored Hemileucas. Peigler and Williams found that lucina would crossbreed with nevadensis but that crossbreeding these US populations produced sterile offspring.
Hemileuca lutea, sometimes classified as yet another species in this group, is now classified as a subspecies of lucina. Lutea means yellowish and these moths have buttercream-colored instead of white, straw-gray instead of blackish gray, bands on their wings. Whether this difference is due to a gene, a difference in diet, or a gene that impels the caterpillars to choose a different diet, remains unexplored.
H. lucina obsoleta is also found, obsoleta being a variant form in which the white band across gray wings is missing, gready narrowed, or reduced to a wedge shape. Why Professor Reiff thought this type looked "obsolete" he did not explain.
Evolutionary biologists have professed bewilderment over why these very similar moths live in the same place. Why do maia and lucina live in the same places? I don't know but, while reading about them and menyanthevora , I noted the thought, "The Creator was having a good time, creating these moths." In the Seventh-Day Adventist worldview, there's no reason to doubt that a loving Creator had fun with the Hemileucas, no doubt originally giving them stiff, sharp bristles, but only after sin entered the world allowing the Evil Principle to fill their bristles with venom. The "giant" silkmoths--Hyalophora cecropia, Eacles imperialis, Citheronia regalis--have caterpillars that are bristly and can chomp, but are not venomous, or dangerous to humans unless some idiot tried to eat them. Why should the ugly little Hemileucas be so much more dangerous than the large, alarming Hickory Horned Devil? It is at least convenient to be able to answer these questions with "Because Adam sinned."
Seventh-Day Adventists I have known did not, but some older Christians did, believe (seriously!) that the wonders of Creation were designed as object lessons for us. At least, we can learn object lessons by thinking about them. Maia, lucina, menyanthevora, and also nevadensis and slosseri, all look very much alike and as if they could eat the same food. They may even try nibbling on each other's natural food; if they eat much of it, it will stunt their growth. They have genetically programmed appetites for different food. For optimal health each one must eat its own food. Like humans who have inherited different food tolerances, they have to ignore any social influence that might come from seeing what the others eat, and eat only their proper food.
Conditions of their early lives affect the way the caterpillars grow in many ways. Because the caterpillars are relatively large, sedentary, and easy to find, researchers did a formal study of how being pestered by predators affects their growth. They found that even when predators aren't able to kill or parasitize stingingworms, they can literally scare the animals out of a few days' growth...by chivying individual caterpillars to hide in the shade, leaving the cluster ahead of schedule, and eat mature leaves while the cluster swarm out into the sunshine and eat new leaves. This stunts the caterpillars' growth and reduces their future fertility. Whatever ideas this study suggests to normal minds, in some parts of New England, Maine, and Canada people are actually trying to protect lucina population levels.
"PubMed? I thought they were about human health?" They are but NIH stores lots of insect studies, on the grounds that insects may affect human health. And in fact the secondary effects of predators on lucina may turn out measurably to parallel the secondary effects of lucina on human health: Teenagers who avoid orchards, meadows, and other wholesome outdoor places because they want to avoid stingingworms spend the more pleasant half of the summer vegetating indoors, after which they are more likely to be out of condition and undermotivated to go outdoors when the weather is alternating between sultry and stormy. This may promote excessive weight gain, flabbiness, laziness, early appearance of cardiovascular disease, greater exposure to television and correspondingly slower acquisition of general knowledge, and the whole complex of denaturatus conditions that make even minimally damaged, otherwise attractive young people repulsive to peers who were less intimidated by stingingworms. I'm not aware of anyone ever having quantified this specific correlation, but there has to be one.
From New Jersey comes a list of native plants that thrive in damp acidic soil, including black cherry trees if you want to attract lucina and several alternatives if you don't.
However, newly hatched maia caterpillars eat oak tree leaves, while newly hatched lucina caterpillars eat meadowsweet. In both species the hatchlings are black and live as much as possible in a clump. Apparently they feel ,most secure with their bristles against each other. Each caterpillar's own bristles keep it from feeling the sting of a sibling's bristles, maintaining healthy breathing space within the cluster of little stingingworms. As they grow bigger, lucinas strip their original host and wander about individually, often eating blackberry, cherry, and other fruit plant and tree leaves just at fruit harvest season. They can eat birch and willow leaves as well as blueberry leaves.
Meadowsweet grows in relatively damp places and weather, making lucina one of the most damp-tolerant members of the group that includes Hemileuca maia, slosseri, and nevadensis. Lucina positively thrives on damp weather. If not as keen on marshy environments as H. menyanthevora, it's certainly different from the desert-dwelling majority of Hemileucas.
\Even for Hemileucas, lucina tend to eclose, fly, and mate early in the morning. In September to early October, on sunny mornings when temperatures permit, females start expanding their wings and abdominal sections, scent-calling males with every breath and stretch, around 10 a.m. Couples spend some time cuddling, usually one to two hours, although they're unlikely to spend time together again. If both of a couple survive long enough to mate again, as in other Hemileuca species, each will try to find a younger mate since both male and female are most fertile the first time they mate.
Photo by Bhillman, White Mountain Park, September. Hemileucas often find ways to mate face to face and may even intentionally enfold each other's wings between their own. (Moths that fly longer often seem motivated to minimize contact during mating, to protect their wings.)
Females flit off, find a potential food plant on which to lay eggs, and continue laying eggs for several hours. Unlike more southern species that lay eggs on smaller plants, lucina lay more than 100 eggs in one place. As in all insect species, most eggs don't hatch and most hatchlings don't live to maturity.
Eggs are dormant in winter and hatch in May.
Photo by Thecaterpillarlab. The moth didn't lay the average of 140 eggs in each cluster all at once; she rested in between several hours of egg-laying.
Caterpillars molt through six skins; in the first three instars siblings usually stick together, in the fourth and fifth instar they gradually wander off on their own, and in the sixth instar they seem solitary. They are more actively obnoxious than most of the Hemileucas seem usually to be. Probably they don't realize that their venomous bristles as obnoxious enough. They can raise their head and tail ends up over their backs, as the Datana genus do, and they do it for the same purpose of hurling particles of partly digested food at a possible attacker. They also bite. Their jaws are not especially sharp, but like other large caterpillars they can chomp with determination.
Photo by Jef, snapped in May near Needham, Massachusette. Hatchlings travel around their host plant as a cluster. Stragglers who aren't touching any siblings' bristles probably feel at risk and, if tachnid flies are nearby, they really are.
Photo by Jackthropod, documenting that some older caterpillars just stay black and gray.
Photo by Arianwen Jones, documenting that some grow brown or yellow bristles. Both of these individuals were photographed in New Hampshire in May.
A diet of cherry leaves seems to produce a black-and-brown skin color pattern in each of the major pests on a cherry tree--tent caterpillars, gyps (spongeys), and stingingworms in succession. The tree has evolved to survive being stripped by tent caterpillars every ten or fifteen years without much effect even on the cherry crop. If it is then stripped by gyps, however, the tree may be really damaged, and there may not be cherries for the stingingworms to discourage people picking. If you live in a place where this sequence of attacks happens, it's worth the trouble to pick out tent caterpillar nests before they eat very many leaves. All Eastern Tent Caterpillars share a surprisingly attractive color pattern: black skins with a silvery white dorsal stripe and some pattern of silvery white and clear cyanide blue on the sides, sparsely covered in soft ginger fur. Gyps are black with wisps of white hair and the distinctive pattern of red and blue dorsal warts when they're most active, but females who spend their extra instar in a cherry tree can have black skin and ginger hair in their final instar, too. H. lucina and cherry-leaf-eating maias can have black or brown skins with black, gray, or brown bristles. Sometimes lucina even have a dorsal stripe. They are more likely to have a thin white ventral stripe between their little black feet than maia are, though maia can have that pattern too. It is not possible for anyone who has observed Malacosoma americana, Lymantria dispar, and Hemileuca (maia or lucina) to confuse these species at any stage of their lives, but people who have only just read a short description are always misidentifying them.
Polistes fuscatus and their sassy little European competitors, P. dominula, are intrepid hunters and have been reported to kill Hemileuca lucina larvae. They attacked single caterpillars, not clusters. "Worker" individuals in both species have their own venomous stings (sexually active adults don't), but they pack far less venom than these caterpillars do. Nevertheless, determined paper wasps have been reported to chew up Hemileuca caterpillars they have killed and tuck bits of caterpillar into nests for wasp larvae to eat. An author who sounds as if he'll believe it when he sees it observes that the precise method they use for killing Hemileucas remains undescribed. I've not seen one of my wasps kill a Hemileuca but I've seen them kill other animals that looked beyond their reach. While a caterpillar is making a fool of itself, trying to work itself up to vomit, a paper wasp is capable of coolly burying her stinger in its head and hauling it in. The size of things paper wasps can carry while flying, relative to their own size, does boggle the mind.
Stinkbugs, which even admirers of wasps find hard to love, have also been known to attack stingingworms, but both the rate of success of such attacks and the number of stinkbugs who are active while stingingworms are active are low.
Some spiders are known to attract the moths to their webs, apparently with scents that smell enough like a young female moth to interest male moths.
The most efficient natural predator on H. lucina, however, is the techinid fly that also parasitizes other large, songbird-daunting caterpillars like tomato hornworms. Tachinid flies harass one caterpillar in a cluster until it drops off the branch where its litter mates remain. This puts the target caterpillar at a disadvantage and the fly is able to lay eggs in its back end. The caterpillar will continue eating even after the baby tachinids chew their way out through its skin and pupate in between its bristles, but will then die before or during pupation. One study found that aboutt one-third of the stingingworms in the area studies (H. lucina) were destroyed by tachinid flies. This valuable ally looks different from a housefly if you take a long close look, but since most people don't care to look closely at flies it's easier to say that tachinid flies resemble houseflies that leave people alone. They're not attracted to our food or our sweat. They keep to themselves, spending most of the time in the fields and woods where their preferred food is crawling about. All we need to do to encourage tachinid flies is make sure we don't spray poisons to kill flying insects generally.
They can be parasitized by braconids, too, and are occasionally killed by mice and birds. No bird regularly eats the caterpillars but some eat the moths.
Then there are caterpillar diseases, like the fungal infection described here. Generally disease pathogens affect either warm-blooded or cold-blooded animals, not both. Plagues can be unleashed on caterpillars without affecting people, or most of their pets or livestock...but of course these plagues rage beyond their intended boundaries and kill many non-target species. In 2003 a writer about the plagues affecting New England's caterpillars wrote wistfully that, in the Blue Ridge Mountains, the big native silk moths were still abundant, from the giant Hyalophora cecropia to H. maia. No more. That fungus infection that reduces a caterpillar's insides to a dark liquid has wiped out our big silk moths and, while I miss Eacles and Anisota and Actias luna, I don't miss our Hemileucas at all.
The writer didn't seem to know that the plague was being spread for the purpose of controlling Lymantria dispar.
Healthy caterpillars in all of these species often grow more than two inches long, typically about two and a half inches. Lucina caterpillars' bristles often form rosettes in the late stages of their caterpillar lives, with a central spike in each rosette, sllowing maximum release of venorm into attackers who grab the caterpillar, relatively less vernom for thosew ho only brush against it. The rosettes, if formed, seem to be brownish or yellowish with the central spikes black; the branching bristles are black or gray. But lucina is almost as variable as maia.
Photo by Slamonde, New Hampshire, doucmenting the yellow rosettes pattern. (In other photos, individuals had fewer pairs of rosettes, or less vividly colored ones.)
They may burrow into the ground or just hide under leaf litter to pupate, usually through most of July, all of August, and usually part (sometimes all) of September. Then they crawl up out of the ground, looking like rather shaggy grubs until their wings expand, and the cycle begins anew.
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