Comparative Community Ecology Reveals Conserved Ectoparasite Microbiomes Amidst Variable Host and Environment...

Area of Science:

• Microbiology
• Ecology
• Entomology

Background:

• The insect microbiome, including maternally inherited endosymbionts, is vital for insect adaptation to nutrient-poor diets.
• The composition and acquisition of non-maternally inherited bacteria in insect microbiomes remain poorly understood.
• These bacteria influence insect health, fitness, and vector competence.

Purpose of the Study:

• To investigate the conservation and variability of bacterial communities in bat flies (Streblidae) beyond obligate endosymbionts.
• To determine if ectoparasite microbiomes differ across geographic locations, between species, or correlate with host/environment microbiomes.
• To explore the acquisition and maintenance mechanisms of non-maternally inherited bacteria in blood-feeding arthropods.

Main Methods:

• Studied two bat fly species, *Trichobius sphaeronotus* and *Nycterophilia coxata*.
• Analyzed bacterial communities in ectoparasites, host bat fur, and cave environments.
• Compared microbiome composition across different geographic sites and between ectoparasite species.

Main Results:

• Ectoparasite microbiomes were highly conserved and specific to each bat fly species.
• Significant geographic variation was observed in the microbiome of host bats.
• Bat fur microbiomes mirrored the composition of surrounding cave environments.

Conclusions:

• Blood-feeding insect ectoparasites actively maintain a distinct microbiome, separate from their hosts and environment.
• This specificity suggests a biological constraint, potentially for meeting nutritional requirements.
• Further research is needed to understand the acquisition and maintenance of these essential bacterial communities.