Back in September, I was finding snails on sidewalks. I wrote about the ones near my office in this post. On one occasion, while picking up the live snails, I also saw this daddy long-legs feasting on a luckless snail that had been crushed to death.
After I took pictures, I picked up the remains of the snail for a closer look. The daddy long-legs remained in the general area and started making short moves in different directions, as if it was searching for its vanished meal. When I put the snail back in front of it, it moved to it and started eating it again.
Some daddy long-legs, also called harvestmen, (order Opiliones) are scavengers feeding on dead animals, including snails and slugs. In addition, one European species, Ischyropsalis hellwigi, is a specialized gastropod predator (Nyffeler & Symondson, 2001).
In this instance, however, we definitely had a case of scavenging. Here is a closer look.
I posted this picture also on BugGuide.net, but it wasn't identified at the time of the writing of this post (7 October).
Nyffeler, M. & Symondson, W.O.C. 2001. Spiders and harvestmen as gastropod predators. Ecological Entomology, 26:617-628.