Ant fauna in megadiverse mountains: A checklist for the rocky grasslands

Abstract

The rocky grasslands, environments locally known as campo rupestre, occur mainly along the Espinhaço Mountains and are considered local centers of biodiversity and endemism in Brazil. However, knowledge of ant species richness (Hymenoptera: Formicidae) in this kind of environment is still poor. Aiming at filling this gap, we compiled information from empirical studies and literature records. We found a total of 288 species of 53 genera and eight subfamilies recorded in rocky grasslands. Myrmicinae and Formicinae were the most representative subfamilies, with 53% and 18% of the total species richness, respectively. The genera with the largest number of species were Pheidole (41) and Camponotus (40). This large number of ant species recorded for the rocky grasslands surpasses those found in other studies conducted in several different places. Ant species richness decreased with altitude; most species occur below 800 m a.s.l. (171), and only a few species occur above1600 m a.s.l. (17). Some genera occur only at a specific altitude (e.g., Azteca and Dolichoderus at 800/900 m a.s.l.; Leptogenys and Labidus at 1400 m a.s.l.), which points out to the potential use of ants as biological indicators. Our results suggest that the rocky grasslands favor high ant diversity. The patterns of ant richness associated with the altitudinal gradient reinforce the idea of considering the rocky grasslands as priority areas for biological conservation. Moreover, we observed a lack of records on the occurrence of most ant species considered in the present study (93%), which shows that Brazilian myrmecologists need to invest more in taxonomy, management, and data sharing.