In December 2012 I found a larva that didn’t quite fit the profile of a caterpillar. I couldn’t resist the temptation to rear it to adulthood to see what the adult looks like.
I found it browsing on Diospyros lycioides subsp. nitens leaves.
Within two days of capture the larva disappeared into the soil inside the container. I gave it a few days and dug up a neat little cocoon in the loose soil.
Much to my surprize the adult looked like a cross between a fly and a wasp. The flagellum is fused into one extended banana shaped segment and it has no “wasp-waist” between the thorax and abdomen, as is typical of all other Hymenoptera. I could only see that from the side, from the top it looked like a wasp to me.
According to a website I visited in January 2013, they are often described as stingless wasps and get their common name from the female’s ovipositor, which unfolds like a jackknife. It functions like a saw blade, allowing her to cut into stems or foliage and deposit her eggs.
Flies from the order Diptera have a single pair of wings. When I photographed this specimen, it unfolded the wings every time my camera flashed to reveal two sets of wings.
Sawfly larvae have six or more pairs of abdominal prolegs, whereas caterpillars have five or less. The sawflies don’t have tiny hooks on the end of the prolegs like those of caterpillars.
Another feature to differentiate between caterpillars and sawfly larvae are the number of eyes called stemmata. The caterpillars have six and the sawfly larvae two.
Although this little critter hasn’t been identified up to species level, I am happy that I have broadened my knowledge about the diversity of the insects found on our property.