Divergence in Gut Bacterial Community Structure between Male and Female Stag Beetles Odontolabis fallaciosa (Coleoptera, Lucanidae)

Abstract

Odontolabis fallaciosa (Coleoptera: Lucanidae) is a giant and popular stag beetle with striking sexual dimorphism and male trimorphism. However, little is known about their intestinal microbiota, which might play an indispensable role in shaping the health of their hosts. The aim of this study was to investigate the intestinal bacterial community structure between the two sexes and among three male morphs of O. fallaciosa from China using high-throughput sequencing (Illumina MiSeq). The gut bacterial community structure was significantly different between males and females, suggesting that sex appeared to be the crucial factor shaping the intestinal bacterial community. Females had higher bacterial alpha-diversity than males. There was little difference in gut bacterial community structure among the three male morphs. However, compared to medium and small males, large individuals were associated with the higher relative abundance of Firmicutes and Firmicutes/Bacteroides (F/B) ratio, which might contribute to nutritional efficiency. Overall, these results might help to further our understanding of beetle–bacterial interactions of O. fallaciosa between the two sexes, and among the three male morphs.

Sex Results in Divergence in Gut Bacterial Community between Female and Male Pardosa astrigera (Araneae: Lycosidae)

“…Contrary to the previous results with high gut bacterial diversity were found in female insects (Han et al, 2017;Mason et al, 2019;Wan et al, 2020;Xu et al, 2016), however, we found male spiders had significantly higher gut bacterial richness than female. Environmental factors have been proved to be an important role in gut microbiota assembly in arthropods (Chandler, Lang, Bhatnagar, Eisen, & Kopp, 2011;Wong, Chaston, & Douglas, 2013), for insects can obtain microbiota from their surrounding environments (Douglas, 2011).…”

“…For instance, Foster (1995) and Zouache et al (2011) considered that male mosquitoes disperse less than female which could be a factor constraining bacterial diversity, Ng, Stat, Bunce, & Simmons (2018) proved that reduced exposure to diverse environmental microbiota could decrease in gut bacterial diversity of insect. Minard et al (2013) found the different nutritional requirements between two sexes of mosquitos affect bacterial microbiota composition (e.g., higher relative abundance of Firmicutes and Firmicutes/Bacteroides (F/B) ratio, which contributed to nutritional efficiency (Wan et al, (2020). As a result, bacteria from generaBacillus and Staphylococcus were detected in male mosquitos, whereas Cryseobacterium , Pseudomonas andSerratia were present exclusively in female mosquitos (Rani, Sharma, Rajagopal, Adak & Bhatnagar, 2009).…”

“…As a result, bacteria from generaBacillus and Staphylococcus were detected in male mosquitos, whereas Cryseobacterium , Pseudomonas andSerratia were present exclusively in female mosquitos (Rani, Sharma, Rajagopal, Adak & Bhatnagar, 2009). Moreover, Wan et al (2020) argued that higher gut bacterial diversity in female might contribute to the vertical transmission. Although many spider species show dramatically different activity habits between the two sexes, which results in different mobility and foraging opportunities (Aisenberg & Peretti, 2011), however, the gut microbiota of spiders influenced by sex was almost ignored.…”

Divergence in gut bacterial community between females and males in the wolf spider Pardosa astrigera

“…Minard et al (2013) also found that the different nutritional requirements between two sexes of mosquitos affected bacterial microbiota composition. Moreover, Wan et al (2020) showed that higher gut bacterial diversity in females might contribute to the vertical transmission. Although dramatically different activity habits between the two sexes were shown in spider variable species, the effect of sex on gut microbiota of spiders was almost ignored.…”

“…Minard et al (2013) also found that the different nutritional requirements between two sexes of mosquitos affected bacterial microbiota composition. Moreover, Wan et al (2020) showed that…”