Beetles are a group of insects that form the order Coleoptera which is the largest of all orders with about 400,000 species. It includes almost 40% of described insects and 25% of all known animal life-forms. ¹⁾

The English name beetle derivates from the Old English word bitela, meaning little biter, which is related to bītan (to bite), and finally leads to the Middle English betylle. ²⁾

In the United States, there are about 100 families of beetles. Weevils are the largest family of insects and the largest family of beetles. ³⁾

The smallest beetle in the world is called Scydosella musawasensis. This on-parasitoid insect is approximately 325 µm (0.325 mm). ⁴⁾

The beetle with the longest body in the world is the titan beetle Titanus giganteus of South America. Its body is 6 in (15 cm) long. ⁵⁾

Tiger beetles are in the runner family that is fierce predators, doggedly pursuing their prey. With their slender legs and elongated feet, they can move very quickly and are the fastest insects running on the ground. ⁶⁾

Individuals of both sexes of the glow-worm (Lampyris noctiluca) differ greatly in appearance. The male is winged, while the larva-like female is not winged. Females have light organs on the underside of their abdomen. ⁷⁾

Cantharid (Latin: Lytta vesicatoria) is a beetle in the oleic family known by the misleading name “Spanish fly”. It feeds mainly on ash trees. For self-defense, the insect produces a highly irritating substance called cantharidin, which has been used as an aphrodisiac since ancient times. ⁸⁾

The Goliath Beetle is the largest insect in the world, with some specimens measuring over 11 centimeters in length. ⁹⁾

The Dung Beetle is known for its ability to roll dung balls that can weigh up to 50 times its own body weight. ¹⁰⁾

The Rhinoceros Beetle is one of the strongest animals on Earth, able to lift objects up to 850 times its own weight. ¹¹⁾

The Jewel Beetle has a metallic sheen that can be used to create vibrant colors in jewelry and other decorative items. ¹²⁾

The Bombardier Beetle can shoot a hot, noxious chemical spray out of its rear end to deter predators. ¹³⁾

The Golden Tortoise Beetle can change its color from orange to metallic gold by flexing its exoskeleton. ¹⁴⁾

The Click Beetle can make a clicking sound by snapping a spine on its thorax to propel itself into the air and escape predators. ¹⁵⁾

The Silphidae (carrion beetles) are used in forensic entomology to determine the time of death of human corpses. ¹⁶⁾

The Hercules Beetle is one of the largest beetles in the world, with males reaching up to 17 centimeters in length. ¹⁷⁾

The Blister Beetle contains cantharidin, a toxin used in traditional medicine and as an aphrodisiac. ¹⁸⁾

Meloidae (blister beetles) are also known as “oil beetles” due to their oily and toxic exudates. ¹⁹⁾

The Bess Beetle is known for its low-frequency vocalization that can be heard from several meters away. ²⁰⁾

The Darkling Beetle can survive in extreme conditions, such as high temperatures and radiation, making them ideal for studying adaptation to harsh environments. ²¹⁾

The Scarab Beetle was considered sacred in ancient Egypt and was featured prominently in Egyptian art and mythology. ²²⁾

The Lady Beetle, also known as the ladybug, is a beneficial insect that helps control pest populations in gardens and agricultural fields. ²³⁾