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INSECTS AND BIODIVERSITY WHAT ARE INSECTS? Their names, classification and relatives Scientific Names Scientists who classify organisms into groups are called taxonomists. They give each living organism a unique scientific name which consists of two parts: genus name and species name. For example, the monarch butterfly's scientific name is Danaus plexippus, Danaus is the genus name and plexippus the species. The name of an insect species is sometimes followed by the name of the person who described it. The Oriental cockroach whose scientific name is Blatta orientalis Linnaeus, was described by Carolus Linnaeus, a biologist who created the binomial (two part) system of classification in the late 1700's. Common Names Although many species have a common name such as "monarch butterfly," there are some that don't because they are rare and hardly ever encountered. Insects that do have common names are usually of economic importance, are abundant and found commonly, or have a distinguished appearance. Classification Organisms are classified within a hierarchical system of groups. They are first grouped into species, then species into genera (sing. genus) and genera into families. Families are then grouped into orders, orders into classes and classes into phyla. The Monarch Butterfly: an example For example, monarch butterflies (Danaus plexippus) belong to the genus Danaus and the family Danaidae or milkweed butterflies. Species within this family are large, brightly coloured butterflies whose larvae feed on milkweed. This family is within the order Lepidoptera which includes both butterflies and moths. Hymneoptera is a different order which includes bees and wasps, beetles are part of the order Coleoptera. These orders are all within the class Insecta. Kingdom: Animalia  Phylum: Arthropoda   Subphylum: Uniramia    Class: Insecta     Order: Lepidoptera      Family: Danaidae       Genus: Danaus        Species: plexippus Insect Relatives Insects belong to the subphylum Uniramia which also includes millipedes and centipedes, the closest related organisms to insects. This subphylum is part of the larger Arthropoda phylum in which there are also spiders and crustaceans such as lobsters, shrimp and crayfish. Trilobites were an important group of early arthropods that have been extinct for 250 million years. All arthropods have an exoskeleton, paired and jointed appendages, segmented bodies and an open circulatory system. Finally, insects belong to the Kingdom Animalia. Kingdom is the largest and most inclusive unit of classification. There are five Kingdoms altogether which include all living organisms, Monera, Plantae, Fungi, Protista and Animalia. Back to top