Cockroach, (order Blattodea), also called roach, any of about 4,600 species of insects that are among the most primitive living winged insects, appearing today much like they do in fossils that are more than 320 million years old. The word cockroach is a corruption of the Spanish cucaracha.
The female produces eggs in egg cases (called oothecae). These are sometimes held protruding from her body or may be glued in protected areas. After the female deposits an egg case, the soft white nymphs emerge. As their exoskeleton hardens, it turns brown in colour. The structure and large size (certain species have a wingspread of more than 12 cm [4.7 inches]) of cockroaches have made them objects of interest in the biological laboratory.
The cockroach prefers a warm, humid, dark environment and is usually found in tropical or other mild climates.
