The Hemiptera family Coreidae includes leaf footed bugs and squash bugs. Leaf footed bugs are named for their leaf-like expansions of the hind tibia and femora. They have four-segmented antennae, large compound eyes and one pair of ocelli, or simple eyes.

All species of Coreidae are phytophagous, that is, plant-feeders. Like all true bugs, the adults are equipped with a beak, or rostrum, a hypodermic needle-like device carried under the head, which it uses to pierce the plant tissue and suck out liquids. They do not simply "suck out sap", they inject a tissue-dissolving saliva and vacuum out the resulting slurry. Bugs cannot ingest solid food, and widespread damage to the plant is a result of these liquefying enzymes. [1]

Some Coreids live in leaf litter, but most nymphs and adults live above ground on their host plants where they may feed on seeds, fruits, stems or leaves.  Many occur on an astonishing variety of plants, while some are restricted to a single host. Most Coreids do not appear to have the numbers to become serious agricultural pests, however some become a problem through their feeding on a single variety of plants; the most destructive of these is probably a squash bug, (a common name applied to bugs in the genus Anasa)  Anasa tristis, which is a pest of cultivated cucurbits. [3]  

I find the Coreidae engaging creatures, being so large and stately - they don't scare easily and don't seem to mind posing for pictures - although this one disappeared rather suddenly, with a quick launch from those strong hind legs and a burst of speed from the huge flying wings.