Cuticular lipids of insects. VI. Cuticular lipids of the grasshoppers Melanoplus sanguinipes and Melanoplus packardii

The cuticular lipids of the grasshoppers Melanoplus sanguinipes and Melanoplus packardii contain 60 and 68% al- kanes and 28 and 18% secondary alcohol wax esters, respectively, with lesser amounts of normal and sterol wax esters, triglycerides, alcohols, sterols, and free fatty acids. All the hydrocarbons are saturated, and four types of alkanes are present: n-alkanes, 3- methylalkanes, internally branched monomethylalkanes, and in- ternally branched dimethylalkanes. The principal n-alkanes in both insects are c29 and (227, with a range from Czl to C33. Trace amounts of 3-methylalkanes of 28, 30, and 32 total carbons are present. The principal internally branched monomethylalkanes are C32 and (234, whereas the main dimethylalkane contains 35 carbons. The n-alkanes do not correspond in chain length to the secondary alcohols. The primary alcohols range from C22 to C32 in both insects, with C24 and C26 predominating. The fatty acids in the triglyceride and free fatty acid fractions range from to C24 in M. sanguinipes and from Clz to CIS in M. packardii.