"Epidermal Streaming" and associated phenomena displayed by Larvae of Chrysomyia marginalis (Wd.) (Diptera: CALLIPHORIDAE) at carcasses

Abstract

Competition with vertebrate scavengers for carrion necessitates blow-fly larvae to make rapid and effective use of dead animals. Blow-fly eggs are deposited in shaded, concealed positions at a carcass, and the larvae need to enter the body to feed on muscle and other soft tissues as soon as possible after eclosion. They do so by digesting away the skin with enzymes, but this is often preceded by an exploratory phase in which larvae migrate over the carcass to find wounds by which they are able to gain more rapid entry into the body. Epidermal streaming is one method of performing this exploratory phase, and involves movement by small larvae below the superficial outermost layer of skin. Several possible benefits of this behaviour are discussed.