Termites and subsocial roaches inherited many bacterial-borne carbohydrate-active enzymes (CAZymes) from their common ancestor.

Termites digest wood using Carbohydrate-Active Enzymes (CAZymes) produced by gut bacteria with whom they have cospeciated at geological timescales. Whether CAZymes were encoded in the genomes of their ancestor's gut bacteria and transmitted to modern termites or acquired more recently from bacteria not associated with termites is unclear. We used gut metagenomes from 195 termites and one Cryptocercus, the sister group of termites, to investigate the evolution of termite gut bacterial CAZymes.

Evidence of cospeciation between termites and their gut bacteria on a geological time scale.

Termites host diverse communities of gut microbes, including many bacterial lineages only found in this habitat. The bacteria endemic to termite guts are transmitted via two routes: a vertical route from parent colonies to daughter colonies and a horizontal route between colonies sometimes belonging to different termite species. The relative importance of both transmission routes in shaping the gut microbiota of termites remains unknown.

The ultrastructure of the intramandibular gland in soldiers of the termite Machadotermes rigidus (Blattodea: Termitidae: Apicotermitinae).

Machadotermes is one of the basal Apicotermitinae genera, living in tropical West Africa. Old observations suggested the presence of a new gland, the intramandibular gland, in Machadotermes soldiers. Here, by combining micro-computed tomography, optical and electron microscopy, we showed that the gland exists in Machadotermes soldiers only as an active exocrine organ, consisting of numerous class III cells (bicellular units made of secretory and canal cells), within which the secretion is produced in rough endoplasmic reticulum, and modified and stored in Golgi apparatus.

Anatomical specializations of the gizzard in soil-feeding termites (Termitidae, Apicotermitinae): Taxonomical and functional implications.

The anatomy of the workers' digestive tube is essential in taxonomical studies of soil-feeding Apicotermitinae termites, especially in soldierless lineages. Two structures, the mesenteric-proctodeal junction and the enteric valve, have long been important to distinguish genera and species. By contrast, the gizzard (proventriculus) has been almost ignored by taxonomists because of its generally regressed state in soil-feeding termites.