488 IX. CAROTENOIDS AND VITAMINS A 



pean limpets (Patella vulgata and P. depressa) have been shown to contain 

 at least five different carotenoids, viz., a- and /S-carotenes, echinenone, 

 cryptoxanthin, and zeaxanthin. A compound resembling astacene was 

 found in one of the Tectihranchiata, the mantled sea-slug {Pleurobranchus 

 elegans)^^* Strain^'^'^ reported the presence of another, hitherto unde- 

 scribed rose-pink carotenoid, hopkinsiaxanthin, in the nudibranch mol- 

 lusc (Hopkinsia rosacea) . 



c'. Insecta: The carotenoids are widely distributed in insects, although 

 the data on their distribution and metabolism are quite limited. The most 

 comprehensive review of this subject is that of Goodwin. ^^- 



a". Coleoptera. A so-called " linacarotene" was reported as early as 

 1893 by Zopf^^^ in the reddish-brown elytras (thickened fore- wings), body 

 wall, and eggs of a large irridescent poplar beetle {Lina populi), and of the 

 small poplar beetle (L. tremulae); it was likewise reported in the yellow 

 juice which they excrete. The same substance was identified by Zopf^^' 

 in the corresponding tissues of the seven-spotted ladybird (Coccinella 

 septempunctata) and in a ladj^bird with five spots (C. quinquepundata) . 

 Although Wall"^ identified carotene in a nine-spotted variety (C novem- 

 punctata), Lederer"*^^ proved that the elytrar'linacarotene" from C. septem- 

 punctata was actually a mixture of a- and /3-carotenes and lycopene. No 

 free xanthophylls were present, but some esterified xanthophylls occurred 

 in the body. 



The early report of Palmer and Knight"^ indicates a similar carotenoid 

 pattern in the Colorado potato bettle {Leptinotarsa (Doryphora) decemlin- 

 eata), i.e., carotene but no xanthophylls. However, Manunta"^ believes 

 that this beetle carotenoid is similar to that extracted from the carmine 

 flamingo {Phoenicopterus roseus), which has been called "phoenicoxanthin." 

 Sweetman and Palmer"^ reported that the confused flour beetle or weevil 

 (Triholium confusum) can exist on carotenoid-free diets; furthermore, it 

 does not synthesize these compounds de novo. Crowell and McCay^" 

 found that the webbing clothes moth (Tineola bisselliella Hum.) required 

 neither fat nor fat-soluble vitamins for growth. 



b". Lepidoptera. Carotenoids were first identified in the hemolymph, 



«o H. H. Strain, Biol. Bull, 97, 206-209 (1949). 



«i W. Zopf, Beiir. Physiol. Morphol. niederer Organ., 1, 30-56 (1892); 3, 3-35 (1892): 

 3, 26-47 (1893). 



«2 R. E. Wall, Ann. Entomol. Soc. Amer., 26, 425-463 (1933). 



«3 E. Lederer, Compt. rend. soc. biol, 117, 413-416 (1934). 



^'* L. S. Palmer and H. H. Knight, J. Biol. Chem., 6.9, 443-449 (1924). 



^^6 C. Manunta, Nature, 162, 298 (1948). 



«« M. D. Sweetman and L. S. Palmer, J. Biol. Chem., 77, 33-52 (1928). 



«' M. F. Crowell and C. M. McCay, Physiol. Zool, 10, 368-372 (1937). 



I 



