nternal insect microbial communities, that is microbe taxa that live within an organism, play important roles in digestion, protection from pathogens, and fitness of their insect hosts. Recent expansion of research in this field has highlighted the importance of endosymbiotic communities to their hosts and elucidated microbial community patterns based on host life history. Here, we document the bacterial microbiome of two species of the butterfly genus Heliconius (Nymphalidae), each from two fragmented populations, by sequencing the V4 region of the 16S rRNA gene. We used 14 individual adult butterflies from two species, Heliconius cydno (n = 10) and H. clysonymus (n = 4), from two forest reserves in the Central Colombian Andes. Commensalibacter (Acetobacteraceae) was the most common bacterial genus across all samples, although relative abundance varied across groups. Notably, we also observed the bacterial genera Spiroplasma (Spiroplasmataceae) and Wolbachia (Ehrlichiaceae). While we did not find distinct spatial or species-level patterns in bacterial composition of microbiomes, we did find disparate bacterial diversity across the two butterfly species, with H. cydno harboring higher diversity than H. clysonymus. The microbiome composition of the two butterfly species did not differ, but that of H. cydno was distinct from the microbiome composition of environmental/butterfly trap bait samples. These findings contribute to the documented diversity of insect microbiomes and inform future experimental and sampling efforts.
