Goliathus; Print; The Goliath beetles (named after the biblical giant Goliath) 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. Goliath beetles can be found in many of Africa's tropical forests; where they feed primarily on tree sap and fruit. Little appears to be known of the larval cycle in the wild; but in captivity; Goliathus beetles have been successfully reared from egg to adult using protein-rich foods such as commercial cat and dog food. Goliath beetles measure from 60-110 millimetres (2.4-4.3 in) for males and 50-80 millimetres (2.0-3.1 in) for females; as adults; and can reach weights of up to 80-100 grams (2.8-3.5 oz) in the larval stage; though the adults are only about half this weight. The females range from a dark brown to silky white; but the males are normally brown/white/black or black/white.