Identification of biogenic amines involved in photoperiod-dependent caste-fate determination during the adult stage in a temperate paper wasp

•Photoperiod is one of the caste-fate determinants in temperate paper wasps.•Brain levels of tyramine and tryptophan differ between short and long daylength.•Tyramine and tryptophan are correlated to ovarian development and lipid stores.•Monoamines play a role in photoperiod-dependent caste-fate determination.