Pigmentation of the marine isopod Idothea montereyensis

Abstract

1. 1. Body and chromatophore pigments were isolated from the three colour varieties of the marine isopod, Idothea montereyensis. 2. 2. The red, green and brown coloration of this species is primarily a result of cuticle pigmentation although general body colour as well as the red chromatophores can modify or enhance cuticle colour. 3. 3. The chromatophore pigment is a reduced ommochrome. 4. 4. The cuticles of all three colour varieties contain lutein, lutein epoxide and canthaxanthin, although the proportions of these differ in each case. 5. 5. Red cuticles primarily contain the reddish β-carotene derivative, canthaxanthin. 6. 6. Green cuticles contain a bluish canthaxanthin-protein complex and relatively large amounts of lutein which may be absorbed on the protein complex or may alternatively be a component of a separate lipo-protein. 7. 7. Brown animals are intermediate in that they contain a mixture of red and green pigments. 8. 8. A possible pathway has been suggested for the production of canthaxanthin from β-carotene.