CUTICULAR LIPIDS OF ADULT LOCUSTA-MIGRATORIA-MIGRATORIODES (R AND F), SCHISTOCERCA-GREGARIA (FORSKAL) (ACRIDIDAE) AND OTHER ORTHOPTERAN SPECIES .2. HYDROCARBONS

1. 1. Wing and body cuticular hydrocarbons of male and female Locusta migratoria migratoriodes (Lmm) and Schistocerca gregaria (Sg) comprise n-alkanes (Lmm, average 41.4%; Sg, average 64.9%, both C14-C36), 3-methylalkanes (Lmm, C25-C31, average 24.3%; Sg, C27-C31, average 1.4%), internally branched monomethylalkanes (Lmm, C25-C34, average 18.1%; Sg, C29-C35, average 16.4%), dimethylalkanes (Lmm, C25 + C31-C37, average 13.0%; Sg, C29-C35, average 14.2%) and trimethylalkanes (Sg, C31-C35, average 1.1%). 2. 2. The slight qualitative differences which occur between wing and body hydrocarbons are confirmed to the n-alkanes and dimethylalkanes. Quantitatively, body mixtures contain higher proportions of long-chain n-alkanes (Sg only) and internally branched monomethyl- and dimethylalakanes (both Lmm and Sg). Only minor differences occur between the male and female hydrocarbons of each species. 3. 3. The hydrocarbons of L. m. migratoriodes and S. gregaria and those of 12 other orthopteran species are compared and the way in which hydrocarbon biosynthesis may have evolved in the Orthoptera is indicated. 4. 4. The cuticular lipid of S. gregaria has a low proportion of unsaturated fatty acids and is probably adapted to a higher rate of environmental temperatures than the lipid of L. m. migratoriodes. © 1990.