Fungus-growing termites (subfamily Macrotermitinae) live in an obligate mutualistic symbiosis with species of the fungal genus Termitomyces (Basidiomycota). Although the species that build large mounds are the most conspicuous, termites of the genus Microtermes construct large underground networks of tunnels connecting many fungus gardens. They are also the only entire genus within the Macrotermitinae in which vertical transmission of the fungal symbiont has evolved. To study patterns of genetic diversity in species of the genus Microtermes and their Termitomyces symbionts, we sampled at three different locations in South Africa and sequenced COI for the termites and ITS for the fungi. We discovered high genetic diversity in both termites and fungal symbionts but very low interaction specificity. This implies that frequent horizontal exchange of fungal symbionts occurs between species, despite vertical transmission across generations. We also estimated colony size based on termite haplotype and fungal genotype combinations and found indications that colonies may extend over large areas.

真菌生长的白蚁（亚科Macertermitinae）与真菌Termmitomyces（Basidiomycota）的种类生活在专一的共生关系中。尽管能筑大丘的物种最引人注目，但白蚁属的白蚁却能建立连接许多真菌花园的大型地下隧道网络。它们也是大白蚁内真菌共生体垂直传播发生的唯一完整属。为了研究遗传多样性的图案属种Microtermes及其蚁巢共生体，我们在南非的三个不同地点取样，对白蚁的COI和真菌的ITS进行了测序。我们在白蚁和真菌共生体中发现了高遗传多样性，但相互作用特异性却很低。这意味着尽管世代之间有垂直传播，但在物种之间仍经常发生真菌共生体的水平交换。我们还根据白蚁单倍型和真菌基因型组合估算了菌落的大小，并发现有迹象表明菌落可能会在大面积上延伸。