Diversity snapshot of green-gray space ants in two Mexican cities

This study evaluates changes in the diversity and composition of ants that inhabit contrasting environmental conditions (green and gray spaces) in two cities of different size and degree of urbanization: Xalapa and Coatepec (Veracruz, Mexico), both of which are surrounded by cloud forest remnants, croplands and pastures. In each city, a green space and a gray space of similar area were selected (~ 31 ha) and ten sampling sites were randomly placed within each environment. Tuna in oil and honey were used as baits to collect soil ants, entomological nets to capture vegetation ants and Winkler sacks for leaf-litter ants. Ant species richness (D-0) and diversity (D-1) was greater in Coatepec (the smaller and less urbanized city) than in Xalapa. However, the pattern observed when comparing green and gray spaces differed between the cities: the greatest diversity (D-0 and D-1) was observed in the gray space of Coatepec and the lowest diversity in the green space of Xalapa. In both cities, the similarity of species composition between habitat conditions was close to 50% and the comparison of green spaces between the cities showed that these are more different to each other than is the case with the gray spaces. These results suggest that the characteristics of each city influence the ant diversity contained in green and gray spaces differently and can promote differentiation in species composition within the same city.