VISUAL PIGMENT DIVERSITY IN 2 GENERA OF MANTIS SHRIMPS IMPLIES RAPID EVOLUTION (CRUSTACEA, STOMATOPODA)

1. Interspecific diversity in the visual pigments of stomatopod crusta ceans was characterized using microspectrophotometry. We examined the 10 visual pigments in main rhabdoms in retinas of 3 species of each of two genera of stomatopod crustaceans of the superfamily Gonodactyloid ea, Gonodactylus (G. oerstedii, G, aloha, and G. curacaoensis) and Odo ntodactylus (O. scyllarus, O. brevirostris, and O. ''havanensis''). Sp ecies were selected to provide a matched diversity of habitats. 2. In each genus, visual pigments varied in lambda(max) in several regions o f the retina, as revealed by analysis of variance. The variation withi n closely related species of the same genus implies that visual pigmen ts can evolve rapidly in stomatopods. 3. In photoreceptors of the peri pheral retina, which are devoted to spatial vision, visual pigment lam bda(max) decreased as the depth range of the various species increased , a typical pattern for marine animals. In contrast, visual pigment la mbda(max) in photoreceptors of retinal regions devoted to polarization vision (midband Rows 5 and 6) is not obviously correlated with the sp ectral environment, implying that polarization information may be conf ined to particular spectral ranges. Visual pigments of the tiered rows of the midband, which are committed to spectral analysis, span a larg er spectral range in shallow-water than deepwater species.