In their late instar stages (third or fourth), Lycaeides subsolanus larvae have a facultative symbiotic relationship with several ant species. In Yamanashi Prefecture, the larvae are tended frequently by worker ants of Lasius japonicus and sometimes by those of Formica japonica. Cuticular hydrocarbons (CHCs) were extracted from wild-caught late-instar larvae of L. subsolanus and the workers of these 2 attendant ant species, and their compositions were determined by gas-chromatography mass-spectrometry (GC-MS). The attendant ants showed species-specific CHC compositions; the major compounds obtained from L. japonicus were determined to be branched alkanes with >29 carbon atoms, while those from F. japonica were determined to be linear alkanes and alkenes with 27 or 29 carbon atoms. The CHC profiles of the third- and fourth-instar larvae were qualitatively similar to each other but remarkably different from those of the attendant ants. The extracts obtained from L. subsolanus larvae contained 11 linear and 4 branched alkanes, the major compounds being nonacosane, pentacosane, heptacosane, and hentriacontane. The CHC profile of L. subsolanus larvae was quite similar to that of the larvae of L. argyrognomon, a closely related species. Our previous studies have shown that the CHC profiles of L. argyrognomon larvae were qualitatively consistent irrespective of the larval instar and the attendant ant species. These results indicate that both L. subsolanus and L. argyrognomon larvae can maintain symbiotic relationships with ants without changing their intrinsic CHC profile.
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