Performance related traits and habitat of the mantis shrimp Rissoides desmaresti are described for specimens collected from the Solent region on the south coast of England, close to the species northern border. Most animals were collected over sub tidal ‘mud’ and ‘sandy mud’ sediments, although new recruits and adults were also found on intertidal mudflats. Winter size-frequency distributions showed evidence of regular recruitment and growth to maturity. The reproductive condition of females was staged according to the colour of cement glands, which developed synchronously with ovaries. Females with ripe ovaries were observed between October and April and animals kept in aquaria deposited and brooded eggs in March and April. Results showed that regular recruitment and large breeding populations can occur close to range borders.