480 IX. CAROTENOIDS AND VITAMINS A 



Although it would seem that astaxanthin is characteristic of the Asteroi- 

 dea, there is equally good reason for considering it to be characteristic of 

 the Crustacea. 



h'. Ophiuroidea: Lonnberg'*^^ demonstrated the presence of carotenoids 

 in a number of species of brittle-stars. According to Goodwin, ^^^ they 

 were found in the epidermis of these stars. Fox and Scheer'*^^ demonstrated 

 that the predominant pigment in one brittle-star {OpMopteris papillosa), 

 in the red-black, spiny brittle-star (0. spiculata) and in the rough serpent- 

 star {Ophiothrix rudis), is a xanthophyll resembling taraxanthin. A pre- 

 viously undescribed pigment which is very unstable also occurs. Pecteno- 

 xanthin is also found in 0. papillosa. One interesting finding is that ^- 

 carotene was completely absent from all of these species. Karrer and 

 Benz'*-^ identified astaxanthin as the pigment in the dark red brittle sea- 

 star (Ophidiaster ophidianns) . 



c'. Holothuroidea: The red-yellow gonads of the Northern sea-cucumber 

 {Mesoihuria (Holothuria) intestinalis) , and the blue gonads of the tentacled 

 sea-cucumber {Cucumaria ladea), were shown'^-'*"' to contain carotenoids; 

 48% of the carotenoid in C. ladea is carotene, while some echinenone is also 

 present. ^^^ 



d'. Crinoidea: Although no measurable amounts of carotenoids were 

 detected in the sea-lily {Aniedon rosacea) j'^^* some have been observed 

 qualitatively in a related crinoid (.4. petasus) .'^''^ 



e'. Echinoidea: The major portion of the carotenoids stored by the echi- 

 noids is present in the gonadal and intestinal tissues. Echinenone is a 

 prominent pigment in this group, and was originally believed to be charac- 

 teristic. Lederer'*^^ first obtained echinenone from the sex glands of the 

 brownish-purple Atlantic sea-urchin {Strong ylocentrotus lividus), and it has 

 since been isolated from the gonads of the edible sea-urchin {Tripneustes 

 esculentus), from those of the Pacific pale sea-urchin (Lytechmus pictus), 

 by Fox and Scheer,^^^ and from those of the straw-colored, burrowing heart- 

 urchin {Echinocardium cordatum) by Goodwin and Srisukh.^-^ jS-Carotene 

 and lutein were also present in the latter organisms. However, echinenone 

 is also Avidely distributed among other invertebrates. Goodwin and 

 Taha^^^ found that it is probably identical with myxoxanthin, isolated 

 from the purple plankton, freshwater alga {Oscillatoria ruhescens) by Heil- 



^24 E. Lonnberg, Arkiv Zool, A 28, No. 6, 1-4 (1936). 



«5 P. Karrer and F. Benz, Helv. Chim. Acta, 17, 412-416 (1934). 



«« E. Lederer, Compl. rend., 201, 300-302 (1935). 



«' T. W. Goodwin and S. Srisukh, Nature, 167, 358-359 (1951). 



428 T, W. Goodwin and M. M. Taha, Biochem. J., 48, 513-514 (1951). 



