There are two kinds of asparagus beetles that like to eat asparagus — the Common Asparagus Beetle (Crioceris asparagi) and the Spotted Asparagus Beetle (Crioceris duodecimpunctata).
The Common Asparagus Beetle is the more economically important one (the more destructive one) of the two species, and is a pest of asparagus both in Europe and in North America. It is less than half-an-inch in length (or roughly 0.3″), with a shiny or metallic blue-black coloration, and with distinctive cream or yellow spots on its red-bordered wing coverings. The larva–of both species–is small, grub-like, and has a dark head, but there are some differences between them. Larvae of the Common Asparagus beetle have dark bodies (as seen in the photos below), whereas the larvae of the Spotted Asparagus beetle are cream-colored, with a light brown head and will most frequently be found inside the berry on female plants.
Additional Information: Asparagus Beetles (Penn State)