Largest Insects in the world

 Goliath beetle :

            The Goliath beetles are any of the five species in the genus Goliathus. Goliath beetles are among the largest insects on Earth, if measured in terms of size, bulk and weight. They are members of subfamily Cetoniinae, within the family Scarabaeidae. 

Titan beetle:

        The titan beetle (Titanus giganteus) is a neotropical longhorn beetle, the only one in the genus Titanus, and one of the largest known beetles. titan beetles are threatened by deforestation and habitat loss. Paradoxically, the interest of commercial collectors in specimens of Titanus may help to save not only the beetles themselves, but the whole ecosystem where they live.

Gauromydas heros:

                     The Mydidae (alternative spelling Mydaidae), or Mydas flies, are a cosmopolitan family of flies. It is a small family, with about 471 species described. They are generally large in size, including the largest known fly, Gauromydas heros (syn. Mydas heros). 

Sources : Wikipedia & Google Images