Body Parts of a Madagascar Cockroach

In contrast to the cockroaches that infest many homes, the Madagascar cockroach is not a pest. Madagascar cockroaches remain in their forest habitat, rummaging through fallen leaves and decaying logs. Their anatomy resembles that of most insects, but they are larger than other cockroaches and possess certain features that give them an individual character.

  1. Exoskeleton

    • The Madagascar cockroach does not have an internal skeleton. A protective covering envelops its internal organs and gives its body a rigid form. This external covering is called an exoskeleton. A cockroach has this exoskeleton as soon as it comes out of its egg. The young, called the nymph, must shed its exoskeleton and grow a new one several times until it becomes an adult. The adult does not molt, but keeps its exoskeleton till it dies.

    Basic Body Parts

    • The Madagascar cockroach has three basic body parts: a head, a middle section (called the thorax) and the abdomen.

    Head

    • The head of the Madagascar cockroach has compound eyes, a pair of antennae, and chewing mouth parts called mandibles. The antennae of male and female differ from one another. The male antennae are ̶0;bushier,̶1; according to the Entomology Department of the University of Nebraska-Lincoln.

    Thoracic Plates

    • The middle section, or thorax, of the Madagascar cockroach subdivides into three sections: the prothorax toward the front, the mesothorax in the middle, and the metathorax in the rear. Tough plates called nota, pleura and sterna give strength to the thorax. Nota are the plates covering the back of the thorax. Pleura are the plates covering the side of the thorax. Sterna are the plates covering the breast of the thorax, according to the Department of Entomology of the University of Minnesota.

    Thoracic Accessories

    • A Madagascar cockroach possesses six legs but no wings, according to National Geographic. The male Madagascar cockroach has structures that look like horns on the part of the thorax right behind the head. They are called pronotal horns because they lie on the pronotum, the part of the thorax just before the plates called nota. Males use these horns to battle a rival when the two wish to mate with the same female. Females have little bumps on the pronotum instead of horns, according to Debbie Clark and Donna Shanklin, entomologists at the University of Kentucky College of Agriculture.

    Abdominal Features

    • The terminal section, or abdomen, contains the reproductive organs of the Madagascar cockroach. Females emit chemicals from the abdomen to attract a male. The females keep eggs in their abdomens until the nymphs hatch. Both male and female Madagascar cockroaches have small breathing pores called spiracles along the sides of the abdomen. These spiracles lead into tubes called tracheae that distribute incoming oxygen to the organs within. The Madagascar cockroach can produce a hissing sound by expelling air forcefully through these spiracles. The males hiss when they are fighting for a mate or when they are courting a female. Both males and females hiss when disturbed or frightened, according to Debbie Clark and Donna Shanklin, entomologists of the University of Kentucky College of Agriculture.