Dynastinae

Dynastinae are a subfamily of the Scarabaeidae, the common name is rhinoceros beetles. There are about 1500 species and includes some of the largest beetles in the world - Megasoma, Chalcosoma and Dynastes.Some can be 16cm in length , and the larvae of Megasoma acteon can weigh 110g. The hercules beetle can lift 850 times its own bodyweight.

They are usually convex and rounded in shape. In rhinoceros beetles the labrum is concealed by a shield called the clypeus. The antennae have 9-10 segments with the last 3 forming a club.

They are called rhinoceros because the males have horns which are used for digging and fighting with males during the mating season. The size of the horns are a good indicator of nutrition whilst a larva. This is because the cells in the horn are more sensitive to insulin-like growth factors (responsible for controlling growth) . This horn sensitivity was demonstrated by disabling the gene that produces IGF.The horns were 16% smaller whilst the wings were only 2 % reduced. The horns originate from the head and thorax. The horns do not seem to impede their ability to fly. The males can live 2-3 years ,the females have a shorter life span often dying shortly after laying about 50 eggs.

The larval stage can last several years when they feed off rotten wood. The adults feed from rotting wood, fruit, nectar or pollen

They are mainly nocturnal and hide in the day , some can create a hissing sound by rubbing the abdomen against the elytra (wing cover). The main predators are birds and snakes .

In Asia the males are sometimes used in gambling fights. Oryctes are eaten in Africa. The amount of protein (40%) is greater than in Chicken (20%) or beef (12%)

A few species have been shown to have "ears" just beneath the pronatal shield, which are tuned to ultrasonic frequencies and are probably used to detect bats