Although white cockroaches in an apartment can be found not so often, but sometimes they still catch the eye - this is where the question arises as to what strange albinos are such, are they not dangerous for humans and in general, whence come from.
Well, if you see such an unusual white cockroach in the kitchen or in the bathroom, then first you should bear in mind that it is no different from the usual red cockroaches except for color - it is not a mutant and not a mistake of nature. Moreover, each red-haired cockroach is milky white several times in its life. True, such transformations happen infrequently, and the white color itself does not last long in an insect, therefore, the probability of seeing a pest in such an outfit is rather small.
What is the reason for such a reincarnation? Let's understand ...
Why are cockroaches white?
The normal color of the outer covers of a cockroach is due to the presence in its chitinous shell (cuticle) of a set of special pigments from the melanin group - by the way, by chemical nature, close to those responsible for the skin and hair color in mammals.
It is interesting
The type of pigment coloring of cockroaches refers to the so-called cuticular coloring, that is, when the pigments are found exclusively in the external integuments of the insect. Since the cuticle is chemically very resistant, after the death of the insect, the color persists for a very long time.
In some insects, the coloring is hypodermal and subhypoddermal — in this case, the pigments are in the soft tissues under the exoskeleton. Often, after the death of an insect, such coloring quickly changes - for example, the blue and green coloring of dragonflies after their death quickly becomes faded, grayish-brown.
Red cockroaches, Prusacks, have their own specific set of pigments, which is different, for example, from Black Cockroaches. Accordingly, the color of the body and the wings of Prusacks is less saturated.
So why are red-haired cockroaches sometimes white?
Small larvae of cockroaches, just hatched from eggs, have very thin integuments of the body, pigments in their chitinous membranes are contained in very small quantities, and therefore, these larvae appear to be white, almost transparent. Literally within a few days (and sometimes several hours), as the chitinous cover develops and pigments develop in it, the cockroaches darken and acquire their typical coloring.
For example, the photo below shows the white larva of the German cockroach (Prusak):
And here are the black cockroach larvae that have just hatched from the eggs of the library:
And then - the dark brown female of the Madagascar cockroach and the snow-white offsprings “born” by her (the Madagascar cockroach belongs to the egg-breeding species, that is, the larvae hatch from the eggs in the mother's body, and only then are born ”into the light - such a mechanism increases the survival of the young generation) :
So, taking into account the fact that every domestic cockroach hatching from an egg, any larva at the beginning of its life has a white body color. Therefore, if you met a small white cockroach in an apartment - you should not think that it is a mutant, it only says that quite recently the ranks of the pests were replenished with 20-30 new small individuals (just as many eggs on average are in the Prusak nettle).
It is interesting
Types of cockroaches , whose females constantly carry capsules with eggs (oteca) at the end of the abdomen until the larvae hatch, turn out to be more adapted to survival in the natural environment and in apartment conditions. For example, in black cockroaches, the female lays capsules with eggs several days after they form, and only a few weeks later the larvae will emerge from such a defenseless capsule. Therefore, a large number of eggs of black cockroaches are eaten by competing Prusaks, and in nature - by beetles, birds and other animals.
But the female Prusacks carry capsules on themselves until the larvae hatch, as a result of which the survival rate of the eggs increases significantly.
But why sometimes in the apartment there are also large white cockroaches, which have long passed the stage of the first instar larvae?
The fact is that as it grows, the hard chitinous cover of the larva (nymph) becomes too small for it - it grows out of it, as a child grows out of its clothes. This shell may slightly stretch, but does not have enough time for the growth of the insect.
Therefore, about 5-7 times before reaching adulthood, the nymph sheds, discarding the old cover. Each time at the moment of molting, an old larva crawls out of an old brownish shell in poorly pigmented, almost white covers that again need from several hours to several days to darken.
The photos below show the faded white Prusak nymph:
It is these grown up larvae or adult white cockroaches emerging from the last larval “costume” of apartment and private houses that are sometimes noticed in kitchens, toilets and bathrooms (in places close to water sources).
Notice the next time you see a white cockroach: most likely, it will not have wings. Still, for 5-6 molts in the larval stage, the insect has only one molt, after which an adult pest with developed wings appears. And taking into account the fact that no more than 20% of insects live to the last molt, the probability of seeing an adult white pest turns out to be quite low.
Here are some more photos of white cockroaches:
On a note
It is obvious that white color strongly unmasks an insect, especially in nature. Therefore, evolution has contributed to the fact that the integuments of the body of cockroaches darken very quickly, almost simultaneously with drying. Therefore, red cockroaches are white quite a short time.
But some species of cockroaches, who do not see the light at all and live in caves, often have a white color throughout their lives. Here, predators do not use sight, and the color of the cockroach does not play an important role in its survival.
White cockroaches in an apartment: why are they so few and where do they occur most often?
As a rule, cockroaches choose secluded places for molting. This is important for survival, because the individual at this moment is most vulnerable: the chitinous exoskeleton is still too soft and, moreover, unmasks the cockroach with its color.
Therefore, it is unlikely that a white cockroach could be found anywhere on the wall or on the table (however, sometimes this is possible when an individual is disoriented due to the action of any insecticide). Usually white cockroaches in an apartment sit in the most secluded shelters, waiting for time after the next stage of maturation.
In an apartment or house, white cockroaches are often found during cleaning (when moving furniture or when raking up piles of rubbish, among which insects like to hide). If the owner of the apartment is “lucky” and he opens such a shelter just after the molt, he may see pests of a milky-white color.
It is clear that white cockroaches do not possess any unique properties and increased danger (as some impressionable tenants sometimes think). They are even more vulnerable than their red relatives, and less mobile. Therefore, to catch and crush such an "albino" is much easier than a normal cockroach.
On a note
The total duration of all the molts and the stay of the domestic cockroach in a white outfit is about 2-3 days over the course of his many months of life. Given that at these moments insects move a little and carefully hide, you can understand why they rarely come across even with a relatively large number of pests in the room.
White cockroaches in nature
In nature and in terrariums of lovers of exotic cockroaches, there are such species of these insects, which in adulthood are almost white or just light colored.
For example, the giant cockroach Blaberus giganteus from South America, which is very famous among terrariumists, has wide translucent wings that cover the bright little body (see the photo below):
Due to the large size (up to 8 cm) and the original color, this species is very different from many of its relatives. At the same time, among the dry leaves, in which he spends almost his entire life, this cockroach is just the bright wings and masked.
The so-called dead head cockroach (Blaberus craniifer) is quite similar to the giant cockroach. On its back there is a pattern that vaguely resembles a human skull, for which this insect got its name. In the photo the cockroach looks black and white:
In general, in the tropics there are a large number of species of cockroaches, which in adulthood have a light (with shades) color. Below in the photos are a few examples.
In all these species, the nymphs have an almost white color for some time after leaving the egg and after molting.
Are there true albino cockroaches?
Purely theoretically, albino cockroaches can occur in populations - both in nature and in apartments. As noted above, the dark color of the cuticle is determined by the pigments melanocytes, related in structure to those contained in the skin and hair of mammals. And if in nature and in laboratories there are albino rats, cockroaches may well exist, in which pigments are not produced at all.
However, in practice, albino cockroaches are almost impossible to meet for two reasons:
- The primary cause of albinism is gene mutations, and their frequency is extremely low (even among the million normal cockroaches there is almost no chance of meeting at least one true albino);
- In the wild nature of an albino cockroach predators destroy the larval stages even at the first larval stages - too much white color unmasks them. In the housing of a person, the life of a white pest is also unlikely to be long, and very few people would understand, an albino is or just a newly faded cockroach.
If you have seen a white cockroach in your house, be sure to share your impressions by leaving a review at the bottom of this page (in the comments box).