Thepanniculus carnosus is a part of thesubcutaneous tissues invertebrates. It is a layer ofstriated muscle deep to thepanniculus adiposus.[1] In humans, theplatysma muscle of the neck,palmaris brevis in the hand, and thedartos muscle in thescrotum are described as a discrete muscle of the panniculus carnosus. Some of the muscles of facial expression in the head are part of the panniculus carnosus. In other parts of the body, the layer is vestigial, and may be absent or may exist only as microscopic, disconnected fibers.
In other animals, the panniculus carnosus is more extensive. For example, the panniculus carnosus in theechidna covers almost its entire body, enabling it to change its shape to a certain degree, most characteristically byrolling into a ball and presenting its spines to a potentialpredator.