Oh, Momotidae! The modest singing of motmots fits with their retiring habits. Most of my encounters with them have been behind a microphone looking at a solid wall of green vegetation. I know they were in there, if my recordings can be trusted. And just as photographs remind you of the thing you photographed, the recordings remind me of the green walls in which my motmots were secreted. Those memories and the sounds themselves are plenty. But if you should happen to see one, well, that is better yet.
The Blue-throated is one of the smaller motmot species, and it has a restricted range, between the Isthmus of Tehuantepec on the west and the Nicaraguan lowlands on the east. This is the middle sector of the Middle American highlands, and it has many endemic species and supspecies. Often such endemics have close relatives in the other two sectors, Mexico west of the Isthmus, and Costa Rica plus western Panama. But such is not the case with the Blue-throated. It is the only highland motmot in Middle America.
The song of this species is a single note, so here we have two birds singing. One squawks occaionally instead of tooting. Mated pairs of all motmot species are reputed to duet. Chances are good this is a duetting pair. I really do think their performance is serene, but in case you would like more, let's try a couple of videos. The first, from eBird, shows you the the sideways wagging of the tail for which motmots are renowned. The second, by Knut Eisermann, shows a Blue-throated Motmot modelling the motmot proclivity for staying in one place. As I have expanded my flycatcher research into Central America, Knut has been my go-to expert for Guatemala.