What Big Eyes You Have

An encounter with a grumpy mantis

Close up of Giant Rainforest Mantis showing raptorial front legs and surprisingly winsome expression. © Bronwen Scott.

This leaf-green lovely is a Giant Rainforest Mantis (Hierodula majuscula). Just a young ‘un — a nymph* — only 75 mm (3 in) long. When fully grown, this species is up to 110 mm (4.3 in). It is the largest mantis in Australia and one of the largest in the world.

What are you lookin’ at? © Bronwen Scott.

Usually found in rainforest in tropical NE Queensland, this one has made itself at home on the potted plants in my collection. (They’re mostly rainforest plants, so fair enough.) It objected to having a camera pointed at it, but elected to move away rather than threaten me and/or the lens. These big insects can display quite an attitude.

Draw me like one of your mante religieuse. © Bronwen Scott.

As with other insects, their two compound eyes are made up of thousands of visual structures called ommatidia. Each ommatidium has a cornea and a pseudocone that focuses light on multiple photoreceptor cells. What the mantis sees is a composite image of its surroundings — a 240⁰ view with a 35⁰ overlap at the front. No wonder they are so good at catching other insects. (In…