Crane Fly Larvae
A favorite past-time of mine is peering under logs and rocks to see what might be living there. (The logs and rocks are carefully replaced in the position in which they were found so as not to disturb the inhabitants any more than is necessary.) Recently I discovered a Crane Fly larva under a rock that was adjacent to a stream – a typical spot in which to find a soon-to-pupate larva. Roughly an inch long, the most distinguishing features are the ridges along its body, and the star-like appendages at the tip of its abdomen. If you examine the appendages closely, you will find two spiracles, through which the Crane Fly larva breathes, located in a recessed area in the center. Although you can’t see a head, it has one that is tucked into its thorax.
The Crane Fly family is the largest family of true flies, in terms of number of species. They can be found in aquatic, semi-aquatic and terrestrial habitats. True flies do not have segmented legs that they can use to hold on to the substrate when they catch their prey. Many Crane Fly larvae feed on decomposing leaves, but those species of Crane Flies which are predators are capable of forming a large knot with the muscles at the end of their abdomen. When they catch prey with their mouthparts, they enlarge the end of their abdomen and wedge the knot between stones in order to anchor themselves.