Moths correspond to insects that belong to the Lepidoptera group, where we also find butterflies, with whom they share certain traits. Longevity is a very variable aspect in the various species of the animal world, so that some only live a few days and others can approach 100 years.
In this article on our site we want to present you with information about the life cycle of moths, so if you have wondered how long a moth lives, continue reading to answer this question.
Moth life cycle
These animals are holometabolous, that is, they present a complete metamorphosis, so the individual that is born is totally different from the adult, both from the anatomical and physiological point of view. In this sense, the life cycle of a moth consists of four phases or stages, which are:
- Egg
- Caterpillar or larva
- Chrysalis or pupa
- Adult or imago
Moths are insects with a great diversity, since there are about 140,000 species, so, despite the fact that the life cycle is common in terms of the stages through which they all go through the types of moths, the duration times, the places where they occur, the seasons and the ways of feeding become more specific according to the species.
Depending on whether they live in temperate, cold or tropical areas, moths have one, two or even more generations per year. Thus, those that live in cold areas usually reproduce only once a year, while those that live in areas with higher temperatures do so at least twice a year.
Egg phase
Moths are animals with internal fertilization and are oviparous, since they lay eggs that have been previously fertilized inside the female. These insects, depending on the species, usually lay their eggs in particular places on the plants, generally associated with the food that the caterpillars will have when they are born.
Thus, for example, the moth known as the pine processionary (Thaumetopoea pityocampa) lays its eggs on pine leaves. In fact, they do it en masse and the eggs have scales that mimic the shoots of these trees, so they camouflage themselves to prevent possible predators. We have another example in the atlas moth (Attacus atlas), which, although the eggs are also placed on plant leaves, in this case they are done in a scattered manner and not in groups. The same laying can occur in other parts of plants, in clothing or even in certain types of food in our homes.
Eggs vary in size, but are usually a few millimeters, are oval or spherical in shape and, depending on the species, laying ranges from less than a hundred to more than a thousand eggs. As for the time this phase lasts, it is generally a few weeks, but when it occurs in regions with cold climates, they can remain in a state of diapause for months, until the most appropriate temperatures for their development are reached.
Caterpillar Phase
The next stage moths go through is the larval stage, also called a caterpillar. In this phase they are characterized by having an elongated body, which is why they are sometimes called worms, and have legs along the thorax and abdomen. This is a very active phase in relation to feeding, in fact it is when these animals eat the most. The diet is mainly vegetable, but there are certain cases in which they consume other insects and remains of decomposing matter. Many moth larvae are classified as pests because, thanks to their mouthparts made up of mandibles, they devour crops of food interest to people.
Now, how long does a caterpillar live? The caterpillar changes over time, but these transformations are mainly related to size and coloration. Although it is common for this stage to be the longest in moths, it also varies from a few months to extreme cases, such as the Arctic woolly bear moth (Gynaephora groenlandica), which presents diapause in the larval stage and its growth can extend for several years due to the low temperatures where it lives.
Because they are active, many species have developed protection mechanisms in the larval stage, thus, some mimic or camouflage very well in the vegetation where they grow, others have chemical substances that, upon contact with the skin or mucous membranes, cause damage ranging from mild irritation to serious allergic problems and even pain.
On the other hand, caterpillars can produce silk to make nests where they are protected from environmental conditions and also to wrap themselves before passing to the pupal stage.
Chrysalis phase
This phase is mediated by the production of certain hormones that initiate the process of change by which metamorphosis will occur, so that the individual will go from an immature state to a mature one. In this stage, the movement of the individual normally stops, although some caterpillars can change places if they need it, and it is common for them to seek a refuge to carry it out, which can be in a plant, cracks or even underground. In addition, caterpillars usually make a cocoon out of silk where they enclose themselves, partially or totally wrapping themselves, which is attached to some substrate.
When transformation begins, the features of the adult can be identified externally in the pupa. Some limbs are lost, as well as the jaws, but others develop to give rise to the definitive legs of the animal, the wings and the proboscis to feed. There is a group of archaic moths that even in the adult state maintain the chewing mouthparts.
But how long does it take for a caterpillar to turn into a moth? That is, how long does this phase last? The time that the chrysalis lasts, likewise, varies in some cases, so it can be a couple of weeks or even months, since diapause may also be present at this stage.
Adult Phase
The last stage of the moth is the adult stage, which is characterized by its short lifespan. Some moths live one or two days and others a few weeks The adult already emerges fully developed and its main function is reproductive, so it is essential to do it in the shortest time possible. Chemical and sound communication play an important role in the reproductive encounter, since most moths are nocturnal, so colors are not very relevant in these cases.
Although many species feed by sucking excretions and liquids from plants, others do not even have specialized mouthparts, so they do not feed and subsist on the reserves they have accumulated from the larval stage, when they did feed. For this reason, many people wonder how long a moth lives without eating and the answer varies depending on the species, but the usual thing is that it is around 24-48 hours.
As an example to better see how much the life expectancy of the moth can vary from one species to another, we can mention that the male of the great nocturnal peacock (Saturnia pyri), as an adult, lives only about 72 hours, while emperor gum moth (Opodiphthera eucalypti) lives about two weeks
Thus, the entire life cycle of moths can last from a few months to years. Now, if when asking how long a moth lives we refer only to the last phase, that of adult, then we see that its duration is a few days.
