What limits the thermal tolerance of octopus embryos? A study along of latitudinal gradient of some American species.

BÁRCENAS, G.; MASCARÓ, M.; OLIVARES, A.; CAAMAL-MONSREAL, C.; MAZÓN-SUÁSTEGUI, M.; URIARTE, I.; GUZELLA, L.; ORTIZ, N.; ROSAS, C.

Saint Petesburg

Congreso; Cephalopod International Advisory Council Conference; 2018

University of South Florida

From a physiological point of view, thermal tolerance is linked with the capacity of organisms to obtain enough energy to satisfy the demands of metabolism. In juvenile forms of aquatic organisms, there are physiological mechanisms that allow them enhance the oxygen supply, and with it the energy production, increasing in this form the thermal tolerance.Octopus embryos have several limitations that prevent the increment in thermal tolerance because: 1) they are in development and many of physiological mechanisms are not active; 2) they are enclosed in a capsule that restring the exchange with the exterior environment and 3) they have an energy supply defined by female and that cannot be improved. During the last five years we has been accumulated data obtained of embryos of six octopus species exposed to some different thermal regimes in attempt, in one hand define the thermal limits of each one and in other hand understand the physiological mechanisms involved in thermal tolerance of species from different environments: three tropical species (O. maya. O. briareus and O. insularis), one sub tropical species (O. bimaculoides),three temperate species (O. mimus and O. vulgaris type II from Brazil y O. tehuelchus) and one sub polar (E. megalocyathus). Using different forms to evaluate the physiological condition and the thermal limits, at the date we have enough information to propose the mechanisms involved in tolerance of octopus embryos to temperature changes.