Gut microbial diversity in stingless bees is linked to host wing size and is influenced by geography

Abstract

Stingless bees are globally important social corbiculate bees, fulfilling critical pollination roles in many ecosystems; however, their gut microbiota, especially fungal communities, are not well characterized to date. We collected 121 bee samples from two species, Tetragonula carbonaria and Austroplebeia australis, across a distance of 1,200 km of eastern Australia, and analysed their gut microbiomes. We found that the gut bacterial richness of T. carbonaria was influenced by geography (latitude and longitude) and positively correlated to an established fitness indicator in insects; namely, host forewing length/size that relates to flight capacity of stingless bees. We characterized the core microbiomes of the two bees and found that they consisted of the bacterial taxa Snodgrassella, Lactobacillus, Acetobacteraceae and Bombella, and the fungal taxa Didymellaceae, Monocilium mucidum, Malassezia restricta and Aureobasidium pullulans. Both host species identity and management (wild or managed) significantly influenced the gut microbial diversity and composition, and similarity between colonies declined as the geographical distance between them increased. This result was also supported by our co-existing network analyses. Overall, we have thoroughly analysed stingless bee gut microbiomes, and provided novel evidence that T. carbonaria bees with larger wings or from more southern populations have higher microbial diversity in their guts.

Incipiently social carpenter bees (Xylocopa) host distinctive gut bacterial communities and display geographical structure as revealed by full‐length PacBio 16S rRNA sequencing

“…Bombilactobacillus and Bombiscardovia ASVs (Figures S7 and S8), and the bacterial genus Schmidhempelia was frequently present in southern but not northern populations of X. sonorina (Figure 1). Sampling location explained 9%-16% of the variation in bacterial composition, more than previous studies examining geographical signatures in honey bees (Ge et al, 2021), stingless bees (Liu et al, 2021) and even some solitary Osmia (Rothman et al, 2020). Although long-read sequences probably enable us to detect such patterns (Table S1), distinctive Xylocopa sociality and patterns of microbial transmission may also contribute to geographical structuring.…”

Lethal and sublethal effects on stingless bee (Partamona helleri) larvae caused by chronic exposure to three agrochemicals

“…Lactobacillus was the main genus detected in the gut of P. helleri. Symbiosis between Lactobacillus and eusocial bees exists in different geographic regions (Kwong and Moran 2016;Liu et al 2021), and this genus plays an important role in the absorption of nutrients, protection against pathogens, and immune system stimulation (Engel and Moran 2013;Anderson et al 2016).…”

A Novel Integrative Methodology for Research on Pot-honey Variations During Post-harvest

“…Melipona quadrifasciata combined microbiome of the previous two groups was caused by the collection of both plant resins and mud-feces (de Sousa, 2021). Arbefeville et al (2017) Interestingly, another study showed that the diversity of the gut microbiome of the stingless bees was associated with host wing size (Fig 8) where the T. carbonaria bees with larger wings from more southern populations had higher microbial diversity in their guts (Liu et al, 2021). Moreover, the core gut microbiome of these Australian stingless bees consisted of a distinct group of bacterial taxa from that observed in honey bees and bumble bees such as Acetobacteraceae, Bombella, Lactobacillus sp., and Snodgrassella.…”

“…Generally, the alteration of the gut microbiota of honey bees is reportedly due to seasonal changes (Kešnerová et al, 2020) and also influenced by geography (Liu et al, 2021). However, differences in the hygienic habits of stingless bees were reflected in the bacteriome of the inner surface of nests.…”