Life cycle (BugGuide): Eggs laid singly on/near carrion. Larvae hatch in a few days, feed in or under carcass, and pupate in a nearby soil cell. Adults overwinter.
Gaint Walkingsticks are usually credited with being the LONGEST insect in North America. This female's body is around five inches long, which is about average for a fully-grown female. Femoral spines on their mid and hind legs are diagnostic for this species according to BugGuide.
"Elf Shoe" markings on the anterior of the pronotum are said to be diagnostic. Hence, common name "Elf Shoe" is sometimes given to this insect. (BugGuide)
Some speculate these colorful moths mimic red maple samaras (the term for the helicopter-like fruit of maples). (See Ohio Birds and Biodiversity by Jim McCormac)
Caterpillar Hosts: Apple, dogwood, hickory, maples, oaks, poplars, and rose bushes. Range: New York to Florida, west to Missouri and Texas. And, yes, the caterpillars are very attractive and do sting. (BAMONA)
Caterpillar Hosts: Plants in the pea family, including alfalfa and various clovers. Adult Food: Nectar from many kinds of flowers including dandelion, milkweeds, goldenrods, and asters. (Source and more info: BAMONA)