Meeting Abstract
Stomatopod crustaceans are known for having one of the most complex visual systems in the animal kingdom. While the adults have historically received the majority of attention, limited work has been focused on larval stomatopods. Stomatopod larvae must survive as planktonic organisms for days to months before settling. One key aspect for survival is the visual system, which is used for a wide range of important biological tasks. It has been generally understood that pelagic crustacean larvae with compound eyes have a single spectral class of photoreceptor. However, recent evidence suggests that stomatopod larvae have the anatomical and molecular structures to support ultraviolet vision. Based on this, the visual physiology of stomatopod larvae was examined using electroretinogram recordings. This work was completed in summer 2019 at the Keys Marine Lab in Long Key, Florida on two species of larval stomatopods. Larvae were dark-adapted and the response of the eye to brief (75 ms) flashes of broadband ultraviolet (peak 330 nm), blue (peak 510 nm), and orange (peak 570 nm) light was recorded. Additional measurements of broadband blue and ultraviolet light were completed under chromatic adaptation with a dim orange light. While larvae were most sensitive to blue light, this chromatic adaptation revealed a secondary response to ultraviolet light, indicating that larvae have sensitivity to ultraviolet light that is higher than is predicted by visual pigment templates. This is some of the first physiological evidence for ultraviolet vision in larval stomatopods, and larval crustaceans more generally. This work is significant as UV vision assists in a variety of behaviors in other marine organisms, and may be important to stomatopod larval ecology.
