CAROTENOIDS 



contains carotenoids even when reared from colourless eggs on a 

 carotenoid-free regime ; the brown variant, on the other hand, never 

 contained carotenoids under any circumstances. 



Lederer ^ * later examined the bright red wings of Oedipoda niiniata 

 and found the carotenoid fraction to consist of a mixture of 

 (3-carotene and an unidentified hydroxy-carotenoid. This pigment 

 has a spectrum very similar to those exhibited by capsanthin and capso- 

 rubin but differs from these pigments in giving a strong blue coloration 

 with HCl. The red spots on the femora of O, miniata contain the same 

 mixture of carotenoids as do the wings. The blue wings of O. coerules- 

 cens, on the other hand, contain only traces of carotenoids. Okay ^ ^ has 

 verified Lederer's results and has put forward evidence that the caro- 

 tenoid(s) exist in the wings as water soluble carotenoid-protein com- 

 plexes. The orthopteroerythrin, obtained by Okay^® from O. minata^ 

 and which he first considered to be a bile pigment, is now also believed 

 to be a carotenoid-protein complex. Other orthoptera having similar 

 chromoproteins with apparently the same carotenoid as the lipid 

 constituent are Acrotylus insubricus, Calophenus italicus, O. schochii and 

 O. aurea. Lately Okay^^ has indicated the presence of caroteno- 

 proteins in the carnivorous Mantis religosa, and in the phytophagic 

 Acrida turrita, Phaneroptera quadripunctata and Isophya kraussi. 

 It is interesting to note that the acridid A. turrit a contained the greatest 

 amount of the complex. It appears that the carotenoid in the wings of 

 Orthoptera is astaxanthin, the free pigment as well as its protein com- 

 plex occurring in the red wings, whilst the blue and yellow wings 

 contain only the free pigment. ^^ A lutein (xanthophyll) protein com- 

 plex occurs in the skin of Lociista {Tettigonia) viridissima^ Tettigonia 

 cantans, and Meconema varium as part of the insectoverdin complex. ^ ^ 



Recent American work^^*^* on Melanoplus bivitattus indicates that 

 its main carotenoid pigment is p-carotene, although a small amount 

 of xanthophylls may be present. ^-Carotene is located mainly in the 

 body cavity and is most concentrated in the gonads. The average 

 amount of ^-carotene present in males and females is 43-6 [jig. and 

 39-6 (jLg. per gram (body weight), respectively ; the concentration in 

 the gonads can reach 266 (Jig./g. Although (3-carotene accumulates 

 in the body cavities of both light and dark phases of the grasshopper, it 

 is deposited directly below the cuticle only in the light phase. 



The first report of carotenoids in locusts is that recorded by Lederer ^ ^ 

 of unpublished work by Volkonsky and himself. This work indicated 

 that the red integumental pigment of young Desert Locusts, Schisto- 

 cerca gregaria, was not a carotenoid but that the yellow pigment of 

 mature insects was. Chauvin ^ ^ reported an unidentified rose-coloured 



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