The larva of the Royal Walnut Moth, known as the Hickory Horned Devil, has a name of its own. Also, this kind of moth is one of the biggest moths in the world. Its wingspan can reach up to 6 14 inches. Native to the Southeast of the United States, this moth. The moth’s intriguing hue includes grey-green wings with orange wing stripes and a smattering of yellow dots. Orange with thin yellow bands makes up the body. When compared to the moth’s caterpillar stage, when it was blue-green, this is a noticeable change. These moths only breed once each season and favor the leaves of hickory, butternut, or walnut trees for egg-laying. Additionally, they’ll make use of sumac, sweetgum, and persimmon leaves. On persimmon leaves, some scientists contend, the larvae grow more quickly and massively.
More About The Royal Walnut Moth
Royal moth adults have enormous wings. With orange or reddish-orange veins and light yellow spots, the forewings are generally gray, tan, or slightly olive in color. More orange-colored hindwings typically have a yellow patch at the base. The body is orange with light yellow markings and has the appearance of fur. Adult males are smaller and have narrower wings, but they share the same pattern and color as females. The male giant silkworms have large, feathery antennae that are used to detect the scents released by the females.
The spectacular hickory horned devil caterpillar belongs to this species and is so well-known that it has its own name. Also, there are seven world’s largest caterpillars. They can grow to a maximum length of 512 inches. There is no way to mistake them, really. Even though the color varies greatly, it is typically green with blue, black, white, yellow, and reddish or orange markings. On the back behind the head are long, curved horns that are orange with bluish-black tips. The rest of the body is covered in a series of smaller spines. The smaller hatchlings are mostly black, while the middle stages are orangish or reddish. Younger stages are spinier, with branching spines along the body.
Life Cycle of The Royal Walnut Moth
- Eggs
It lays oval, yellowish eggs with a diameter of 2 mm. They prefer nut trees like Juglans and Carya, where they are laid singly or in groups of up to four on the upper surface of the host plant leaves (walnuts and hickories). There are regional preferences, with sweet gum and persimmon being used in the south, and sumacs being used in places where the other fruits are not readily available. In later stages, larvae are solitary and infrequently present in numbers great enough to result in defoliation; however, during the ravenous fifth instar, a single larva can strip several branches of their leaves.
- Larvae
Seven to ten days after the eggs are laid, tiny yellow larvae that quickly turn dark emerge. In their early stages, the caterpillars are lone night feeders; however, as they mature, they curl up in a “j” shape during the day and resemble two-toned bird droppings.
The caterpillars eat during the day as they get older. They undergo four moults. Each instar is distinct, but the fifth and final instar is when they change to a bright green color and develop enormous red horns with black tips, giving them the nickname “hickory horned devils.” They can reach a length of 15 centimeters (5.9 in) and feed heavily on their host plant for 37 to 42 days. The larva is harmless and one of the easier to-handle members of the Saturniidae, despite its frightening appearance. The spines, while prickly, do not sting.
- Pre-Pupation and Pupation
When the larva is about to pupate, it expels its gut, turns turquoise instead of green, and its skin becomes stretched, shiny, and tight. They then descend to the host plant, where they bury themselves in the ground for five to six inches, pupating in a well-formed chamber. The pupae have a relatively short cremaster and are dark brown or black in color. Some pupae overwinter for two seasons, possibly as a defense against unpredictable and unfavorable circumstances like fires and flooding or to preserve genetic diversity over generations.
- Adult
The moths must pump fluid (hemolymph) into their wings to extend them when they close (emerge). The male’s large, plumose antennae enable it to detect the pheromones that the females emit. Males will fly great distances to find a female. The female moth spends the majority of the rest of her life after mating laying eggs, while the male may mate multiple times. These moths have reduced mouthparts in their adults, which are known as vestigial mouths. As a result, they do not eat and only survive as adults for about a week.
Throughout the extended growing season, moths have been observed. There is a clear bell curve to the emergence, with peak weeks coinciding with the first spell of the humid summer weather, which may synchronize emergencies. Citheronia regalis is typically a midsummer moth, on the wing from late June through August with larvae peaking August through October.
Range of The Royal Walnut Moth
In the American Deep South, Citheronia regalis is regarded as a common species; as one moves further north, it becomes rarer and more sporadic. It can be found all over the deciduous forests in the United States, from Missouri to central Florida and from Pennsylvania to Massachusetts. The species, which had previously been observed all over New England, experienced a decline in the Atlantic Northeast in the middle of the 20th century.
Citheronia regalis achieves range stability in the mid-Atlantic states and southern Appalachia, starting from southern New Jersey and moving west through the Ohio Valley, the edge of the Great Plains states, and south to East Texas, excluding the scant contemporary records from New York. In the US state of Connecticut, it is listed as a species of special concern and is thought to be extinct.
Habitat and Conservation of Royal Walnut Moth
Like most other moths, regal moths are most prevalent in areas with a large number of their food plants. This species prefers deciduous woodlands with lots of black walnuts, hickories, sumacs, persimmon, sycamores, etc. as their habitat. This explains why the Ozarks and eastern Missouri—the regions of our state that are more heavily forested—an area where you can find them most frequently. When they are drawn to lights at night and fly between 9:30 p.m. and midnight, people typically only see adults. both midnight.
Food of Royal Walnut Moth
The adult moths of this species, like the majority of other giant silkworm moths, have smaller mouthparts and do not feed. However, a variety of tree and shrub species’ foliage is consumed by the caterpillars. Top of the list is hickories (Carya), which include pecan, and their close relatives, black walnut, and butternut. Because of this, the caterpillars are known as hickory horned devils. Additionally consumed are sweet gum, sycamore, ashes, lilac, and cotton. The preferred larval foods in Missouri are persimmon, butternut, different species of sumac (Rhus), and black walnut.