The larval stadia of L. forficatus are easily distinguished by the number of legs and are separated from all other Scandinavian species in having more than 2+2 teeth on the forcipular coxosternite. The variation during development in size, number of coxal pores, ocelli, antennal articles, teeth on forcipular coxosternite, spinulation, projections on tergites 9, 11 and 13, accessory apical claw on the 15 th pair of legs and genitalia are described. Also the difference between male and female and correlation with size within each stadium are given. The number of coxal pores is the best feature for separating the post-larval stadia of L. forficatus. There are probably 9 post-larval stadia in Sweden. The larva media (sensu Verhoeff) is an accidental stadium and only occasionally included in development.