Entomologists find new wasp species which relies on damselfly to procreate

Staff writer, with CNA

Tue, Aug 27, 2013 - Page 4

A team of entomologists from National Taiwan University have discovered a new species — a tiny wasp that relies on damselflies for procreation.

After its verification with the help of experts from the British Museum, the team announced the discovery and solved the mystery of eggs found inside the eggs of damselflies, which are laid on fallen leaves submerged in water.

Professor Ko Chiun-cheng (柯俊成) and doctoral student Shih Yuan-tung (施圓通) of the university’s Graduate Institute of Entomology first observed the wasp riding on the back of a damselfly, known as Psolodesmus mandarinus, in New Taipei City (新北市).

The newly discovered wasp belongs to a genus which contains just four other described species, all from South America.

The wasp, named Hydrophylita emporos, is the first species of its subgenus that has been found in Asia and the first observed transporting itself on another living organism. Adults of the species measure only 1.2mm in length.

“The specific epithet emporos means ‘passenger’ in Latin, reflecting the phoretic behavior of adult females,” the entomologists said in a paper published in the open-access journal PLoS ONE.

They found that female wasps would wait by the water for damselflies to lay their eggs. When a damselfly arrives, a wasp would land on its back and ride on its back as it walks into the water to lay eggs, and then lay its own eggs inside the eggs of the damselfly.

It takes one to three days for the wasp eggs to hatch and the larvae feed on the damselfly eggs to survive.

The team will next study the body mechanism that allows the larvae to swim to the surface of the water, Shih said.