mealybug, (Oniscidea) also known, depending on the region, as piglets, marranitos, ground pigs, cochineal, moisture bug or the most common of all, ball bug.

You may not know that they are not insectsThey are crustaceans.

The mealybug is a very common crustacean throughout the world.


The mealybug has a flat body. The head and abdomen part are tiny, but the thorax is large (compared to other parts), and it is also made up of seven superimposed individual hard plates. The abdomen is made up of 7 joints. It has a stomach consisting of 6 tiny joints.

They have 7 pairs of legs, and each leg has a round shape. The end of the mealybug's tail has 2 antennae. The first antenna is small, and the second antenna is similar and huge. The second antenna has several joints. The mealybug is similar to the bed bug; if touched, it changes to a protective ball shape, but the mealybug does not change to a ball shape completely. That is the difference between a bed bug and a mealybug.

The pale spots on the exoskeleton of some mealybugs are storage areas for calcium, an important mineral for animals that must build a new shell each time they molt. They first molt their posterior half, then their anterior half, sometimes consuming the fused exoskeleton (exuvia).

Land crustaceans?

Most crustaceans are aquatic and marine, but fewer are common in freshwater, and even fewer have escaped the aquatic realm over evolutionary time, and include terrestrial isopods, of which the mealybug is one of them. .

Aquatic crustaceans have rows of gills for aquatic respiration, but terrestrial crustaceans breathe using some of these same modified appendages for air respiration. Aquatic crustaceans have rows of gills for aquatic respiration, but terrestrial crustaceans breathe using some of these same modified appendages for air respiration. The branched appendages have evolved on modified hind legs, associated with an abundant blood supply for the transport of respiratory gases. These structures must be kept moist, as the gases diffuse through the water. Thus, terrestrial isopods must live in humid places, although this species can exist in relatively dry areas. Many adaptations serve more than one function; rolling up the body probably reduces water loss.


These animals are nocturnal and generally solitary, they live close to their food source (decomposing wood)

The mealybug is a small herbivorous


Mealybug habitat is found in a wide range of habitats, generally wet, and can be found by turning over rocks and eating decaying wood.


This species is of European origin, but it has been widely introduced to North America, where it is quite common today. Right now we can find these terrestrial crustaceans practically anywhere in the world.


Like other terrestrial isopods, mealybugs feed on detritus (decomposing plant matter), but they also feed on algae and lichens that grow on surfaces such as tree trunks and walls.


Their predators are mostly invertebrates like beetles, centipede and a specialized type of Spider that can penetrate your exoskeleton with its chelicerae narrowly pointed.


The male of these crustaceans courts a female by waving his antennae and licking and beating his potential mate. After fertilizing her on one side, he will move to the other side to copulate again. The fertilized eggs are kept in a bag under the body until they hatch, and then come out of the bag to appear as if the female is giving birth alive. Females can store sperm from a single fertilization for up to a year; therefore, they can determine when their young will be released into the world, presumably at an optimal time for survival.

It has a fairly hard exoskeleton that closes like a ball, for self-defense.

State of conservation

The mealybug exists in almost any part of the world and in an infinity of environments, they are very adaptable animals as long as they find a little humidity, for this reason this small animal is classified as Least Concern (LC)

Relationship with humans

This animal is among the animals that generate delight and curiosity when one curls into a ball every time it is disturbed, presumably an anti-predator adaptation. Because of this, these small invertebrates are sometimes kept as pets. To add a new word to your vocabulary, this bending behavior is called congestion.

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