The Blue Crab

Anatomical Adaptation for Swimming of the Maryland Blue Crab (Callinectus sapidus)

The Blue Crab (Callinectus sapidus) has a paddle shaped fifth leg called a swimmeret. This unique anatomical adaptation allows the Blue Crab to swim backwards through the water whether to escape predation, catch food or complete a lengthy migration during mating season.

The swimmeret is composed of six hard shell structures, the distal two being the paddle shaped propodus and dactyl. There are five uniaxial joints along its length. Each joint is connected by a flexible membrane. The joints and connecting membrane give the swimmeret an extensive range of motion.

  • Format: Full size poster or print
  • Client: Johns Hopkins School of Medicine
  • Media: Graphite on Strathmore 500 series Bristol, Adobe Photoshop
  • Size: 13″x 19″
  • 12 | 2015