The local extinction of one of the greatest terrestrial ecosystem engineers, the giant armadillo (Priodontes maximus), in one of its last refuges in the Atlantic Forest, will be felt by a large vertebrate community

Priodontes maximus is the largest living armadillo and is at risk of extinction. The species ranges throughout South America and one of its last refuges in the entire Atlantic Forest is a reserve complex called Sooretama. We investigated the conservation status of the species and its role as an ecosystem engineer in Sooretama. We employed camera-traps, active searches and checked the data from previous studies in the area. In the past 14 years, there were 70 records of the species in 31 sites, including 43 camera-trap images, 25 excavations and two carcasses. However, our recent field work (2018–2019) recorded images of only three adult individuals (a female, a male and one of unidentified sex) and one excavation with evidence that poachers had killed its occupant. We observed through camera-traps that at least 37 vertebrate species used monitored excavations. The species-richness detected in sites with excavations was greater than in sites without excavations. The number of species using excavations of P. maximus in Sooretama was one of the greatest recorded among studies carried out in different biomes. The interior of excavations tended to be used mainly by ground foraging stratum species and by invertebrate and omnivore diets species. This study demonstrated the important role of P. maximus as an ecosystem engineer in the Atlantic Forest. However, unless the course of its imminent extinction can be reversed, P. maximus soon will not be able to play its important ecological role in the Sooretama region.