The eyes of two talitrid amphipods: differences in structure may reflect different behaviours

In this study compound eyes of two species of talitrid amphipods: Talorchestia spinifera from Asilah (Atlantic coast of Morocco) and Talitrus saltator from Oued Laou (Mediterranean coast of Morocco), Maremma Regional Park and Palizzi Marina (Tyrrhenian and Ionic coasts of Italy) were compared. Both T. spinifera and T. saltator possess compound apposition eyes, with ommatidia separated by a connective coating which is thicker in T. spinifera and incomplete in T. saltator. The lenses of each ommatidium are crossed by a vesicular structure (previously undescribed) that differs between the two species for its whole orientation across the eye. This different arrangement of the structure in the two species suggests a number of specific adaptations to their visual habitats. These adaptations are discussed.