Thermal tolerance of embryos and planktotrophic larvae of Archaeopneustes hystrix (A. Agassiz) (Spatangoidea) and Stylocidaris lineata (Mortensen) (Cidaroidea), bathyal echinoids from the Bahamian Slope

Thermal tolerances of early embryos and echinopluteus larvae were studied for two common bathyal echinoids, Archaeopneustes hystrix (A. Agassiz) and Stylocidaris lineata Mortensen. Both species have adult distributions centered at a depth of 550 m on the slopes of the Bahamian Islands, though A. hystrix extends to a shallower depth than S. lineata. Early embryos incubated at 4 temperatures in laboratory incubators developed at the same rates as embryos transplanted by submersible to depths having comparable temperatures. Embryos of both species could tolerate temperatures as high as 25°C.