The influence of temperature on the duration of the embryonic and larval development in Necora puber (L., 1767) was studied. Nine different temperatures were used for the eggs and seven for the larvae, in both cases ranging from 2 to 35°C. The temperature range where visible development was obtained was between 4 and 31°C, with the lowest lethal temperature (temperature at which the eggs did not show any sign of development and development did not resume when the eggs were placed at 15°C) being between 2 and 4°C and the highest lethal temperature between 31 and 35°C for both eggs and larvae.
Temperature was found to be inversely related to developmental time. The incubation period (D) fluctuated between 76 days at 10°C and 17·6 days at 25°C, with an increase in the rate of development (100/D) from 1·13 to 5·55 between these two temperatures. The larval period varied between 48·5 days at 15°C and 28 days at 25°C with rates of development of 2·08 and 3·57 respectively. The adjustment equations used show that temperature has a greater accelerating effect on eggs than on larvae. A simple potential equation, D=aT, describes the relationship between temperature and developmental time better than the Belehrádek equation, D=a(T-t).
Acording to the fitted equations developmental time from spawning to the first postlarval stage is completed in 91–105 days at temperatures of 13–15°C which is very close to our experimental data. The model proposed also fits most of the data from the available literature even those for other species such as Liocarcinus holsatus (Fabricius, 1798) and Carcinus maenas (L., 1758), which suggests that a similar response of developmental time vs temperature could be expected from other related Portunidae.