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Background  The honeybee ( Apis mellifera ) represents a model organism for social insects displaying behavioral plasticity. This is reflected by an age-dependent task allocation. The most protruding tasks are performed by young nurse bees and older forager bees that take care of the brood inside the hive and collect food from outside the hive, respectively. The molecular mechanism leading to the transition from nurse bees to foragers is currently under intense research. Circular RNAs, however, were not considered in this context so far. As of today, this group of non-coding RNAs was only known to exist in two other insects,  Drosophila melanogaster  and  Bombyx mori . Here we complement the state of circular RNA research with the first characterization in a social insect.    Results  We identified numerous circular RNAs in the brain of  A. mellifera  nurse bees and forager bees using RNA-Seq with exonuclease enrichment. Presence and circularity were verified for the most abundant representatives. Back-splicing in honeybee occurs further towards the end of transcripts and in transcripts with a high number of exons. The occurrence of circularized exons is correlated with length and CpG-content of their flanking introns. The latter coincides with increased DNA-methylation in the respective loci. For two prominent circular RNAs the abundance in worker bee brains was quantified in TaqMan assays. In line with previous findings of circular RNAs in  Drosophila , circAm rsmep2  accumulates with increasing age of the insect. In contrast, the levels of circAm rad  appear age-independent and correlate with the bee’s task. Its parental gene is related to amnesia-resistant memory.    Conclusions  We provide the first characterization of circRNAs in a social insect. Many of the RNAs identified here show homologies to circular RNAs found in  Drosophila  and  Bombyx , indicating that circular RNAs are a common feature among insects. We find that exon circularization is correlated to DNA-methylation at the flanking introns. The levels of circAm rad  suggest a task-dependent abundance that is decoupled from age. Moreover, a GO term analysis shows an enrichment of task-related functions. We conclude that circular RNAs could be relevant for task allocation in honeybee and should be investigated further in this context.    Electronic supplementary material  The online version of this article (10.1186/s12864-018-5402-6) contains supplementary material, which is available to authorized users.

Sequence and structural properties of circular RNAs in the brain of nurse and forager honeybees (Apis mellifera)