A List of the Twenty-Nine Insect Orders

With over 750,000 named insect species in the world, trying to identify an insect can be a daunting task. Becoming familiar with the twenty-nine insect orders is an important step in learning to identify and study insects. This list includes the name of each order, the major insect groups in that order, and the group’s approximate number of species worldwide.

Wingless Insects (Subclass Apterygota)

• Order Thysanura (Silverfish and Firebrats) – 600 species
  
  
• Order Diplura (Diplurans) - 400 species
  
  
• Order Protura (Proturans) - 70 species
  
  
• Order Collembola (Springtails) - 2,000 species

Winged Insects with Incomplete Metamorphosis (Superorder Exopterygota)

• Order Ephemeroptera (Mayflies) - 2,100 species
  
  
• Order Odonata (Dragonflies and Damselflies) - 4,500 species
  
  
• Order Plecoptera (Stoneflies) - 3,000 species
  
  
• Order Grylloblatodea (no common names) - 6 species
  
  
• Order Orthoptera (Crickets, Grasshoppers and Locusts) - 17,000 species
  
  
• Order Phasmida (Stick and Leaf Insects) - 2,000 species
  
  
• Order Dermaptera (Earwigs) - 1,000 species
  
  
• Order Embioptera (Web Spinners) - 170 species
  
  
• Order Dictyoptera (Roaches and Mantids) - 6,000 species
  
  
• Order Isoptera (Termites) - 2,000 species
  
  
• Order Zoraptera – (no common names) - 16 species
  
  
• Order Psocoptera (Book Lice and Bark Lice) - 2,000 species
  
  
• Order Mallophaga (Biting Lice) - 3,000 species
  
  
• Order Siphunculata (Sucking Lice) - 500 species
  
  
• Order Hemiptera (True Bugs) – 70,000 species
  
  
• Order Thysanoptera (Thrips) – 5,000 species

Winged Insects with Complete Metamorphosis (Superorder Endopterygota)

• Order Neuroptera (Lacewings) – 5,000 species
  
  
• Order Mecoptera (Scorpionflies) – 300 species
  
  
• Order Siphonaptera (Fleas) – 1,800 species
  
  
• Order Coleoptera (Beetles) – 350,000 species
  
  
• Order Strepsiptera (Stylops) – 400 species
  
  
• Order Diptera (True Flies) – 90,000 species
  
  
• Order Lepidoptera (Butterflies and Moths) – 100,000 species
  
  
• Order Trichoptera (Caddisflies) – 6,000 species
  
  
• Order Hymenoptera (Ants, Bees, and Wasps) – 120,000 species

Sources:

"ABRS - Numbers of living species in Australia and the World Report - Invertebrates"; Accessed 10/20/2007
“Classification of Insects”; Accessed 10/20/2007