CONICET | Buscador de Institutos y Recursos Humanos

The development of cephalopods early life stages is strongly influenced by environmental variables, especiallytemperature. Octopus tehuelchus (d?Orbigny, 1834) is an Atlantic Patagonian fishery resource currently being studiedas a new species for cultivation; however it is not known how temperature modulates its early life stages. In this work,egg masses were artificially incubated at 13 and 16°C under controlled aquarium conditions. In each thermaltreatment, the stages of embryonic development, embryo morphometry and survival throughout embryogenesis, aswell as embryogenesis duration were recorded. After hatching, the morphological description of the juveniles wasachieved and survival time in starvation was calculated for both temperatures. At 16°C the mean embryonic durationwas 85 days shorter than at 13°C. For both thermal treatments, the highest mortalities occurred up to the beginning oforganogenesis, and no significant differences in hatching success were observed. The temperature also showed thepotential to increase or decrease the juvenile performance at the early post hatching period. This resulted in asignificant reduction in size and weight of new born juveniles at 13°C but also in an average increment of 7 days intheir survival in starvation when compared to octopus reared at 16°C. The chromatophore pattern was similar for boththermal treatments and was characteristic of juveniles of this species. The observed differences seem to showadaptive mechanisms that optimize embryos and juveniles viability under the different environmental temperatures thatcan be found in the northern Atlantic Patagonian coast. From a practical point of view, our findings are important todefine the biological parameters and associated procedures for the cultivation of the early life stages of O. tehuelchus.