Mountain Katydid (Acripeza reticulata)

A few weeks ago, Angus Martin found this grasshopper-like insect at his place at Marraweeny. Here’s his account…..This is the critter I mentioned at the SNAP meeting on 23/01/11.  I lodged the specimen at the Museum and this is what I was told about it:

“It is a male specimen of Acripeza reticulata (Tettigoniidae), commonly called the Mountain Katydid. The following link is from the CSIRO site and has an illustration and distribution map of the species. While it is called the Mountain Katydid and can be extremely common in the Alps, it is found across Eastern Australia and we have a specimen in our collection from Warrnambool.”

According to the CSIRO book The Insects of Australia, (Melbourne University Press, 1991), the species is sexually dimorphic with the males being elongate and fully winged, while the females are robust and bear shell-like tegmina (forewings) but lack hindwings. When either sex is disturbed, the tegmina are raised to reveal brightly coloured red and blue bands on the abdomen. David Rentz in his book Grasshopper Country, (University of New South Wales Press, 1996) says, “red, blue, black and traces of white seem to convey to vertebrate predators that the katydids are distasteful. Droplets of body fluid, perhaps distasteful, can be seen emanating from the intersegmental membranes as further protection from the uninitiated bird or lizard.”

And I remember reading somewhere that the bright colour patches also have a “startle” function; that is, when the wings are closed the animal is drab and inconspicuous but when disturbed it opens it wings, and the sudden flash of colour may
distract or divert a predator while the katydid shoots through.

Active by day at Wonganookah Track, Marraweeney; one of two specimens seen; 22 January 2011.

Photos by Sue Martin.