Taro Beetle (Papuana spp.) is a major pest of taro in Papua New Guinea, Solomon Islands, Vanuatu, New Caledonia, Fiji and Kiribati. It is also present in New Caledonia, but damage to taro is not as significant as in other countries. Taro is an important crop in the Pacific islands. It is a lucrative source of foreign exchange where it is exported, plays an important role in traditional ceremonies and a stable food item for many Pacific islanders.

Taro beetle damaged corms are poor in quality and not good for exports. They can be sold to local municipal markets. Badly damaged corms are not good either for home use and are given away as animal feed. The movement of people taking along with them taro planting material is the most common pathway to disperse the taro beetle. Traditional ceremonies where people from different places gather and bring taro, among other things, to meet their social obligations increases the risk of further spreading the beetle to new areas.

Distribution
The taro beetle is known to originate in the Papua region - eastern Indonesia to eastern Papua New Guinea and subsequently spreading to the Melanesian countries including Kiribati.

Fiji and Kiribati each have only one species of the taro beetle - Papuana uninodis and Papuana huebneri respectively. The beetle is known to be present in Kiribati since 1930s. In Papua New Guinea there are over 18 species, the common ones of which are Papuana woodlarkiana, Papuana huebneri, Papuana trinodosa, Papuana biroi, Eucopidocaulus tridentipes and Papuana szentivanyi. Solomon Islands also has several species and records vary from 12 to 18 species. Vanuatu has more than 5 species of the insect, but this number varies from island to island. In New Caledonia the taro beetle species has not been fully authenticated.

Breeding
Generally, the male beetle is less mobile compared to the female. The male makes provisions (tunnels inside the corm) and waits for the female to come, feed, get mated and fly back to the breeding site. Life cycle of a beetle averages around 140 to 150 days. The breeding sites are usually areas associated with high organic matter such as heaps of saw dust, manure, mulch, rubbish dumps, rotten logs/stumps etc. After mating the female will look for a breeding site to lay eggs. Each female can lay up to 100 eggs. Eggs hatch in 11 to 16 days. The larvae molts three times (three instars) before it pupates and finally emerges as an adult.

An adult Taro Beetle.

Quarantine measures are now in place in many of the Pacific Island countries where the beetle is not present.

For more information on taro beetles please contact PPS Entomologist, Sada Nand Lal or Taro Beetle Technician, Fereti Atumurirawa.