Neuroanatomy of stomatopod central complexes offers putative neural substrate for oriented behaviors in crustaceans

All insects studied to date possess a centrally located group of neuropils, known collectively as the central complex, that has been implicated in sensory integration and motor action selection. Among the functions prescribed to the central complex, none is perhaps as intriguing as its role in orientation and navigation. Neurobiological correlates of both current and desired headings have been described in insect CXs. Despite the diversity of arthropods, understanding of the CX as a navigational center originates entirely from terrestrial insects. Stomatopod crustaceans, commonly referred to as mantis shrimps, form an order of predatory marine crustaceans with intricate and diverse visual systems that maintain the distinction of being the only fully aquatic animal known to utilize the navigational strategy of path integration. They utilize idiothetic, celestial, and landmark cues to orient in the benthos. Here, we investigate the neuroanatomy of adult and developing mantis shrimp central complexes and associated neuropils to begin understanding this brain region in a sensorially and behaviorally complex crustacean.