Elevational gradients cause variation of abiotic and biotic factors. These factors may change the environment experienced by different organisms, for example, aquatic insects as dragonflies and damselflies (Odonata Order) This study aims at evaluating how the diversity of Odonata varies with elevations in the island of Puerto Rico. We focused on the order as a whole and on the most abundant species. We conducted a survey of Odonata species by dividing Puerto Rico into eight zones and collecting in each. This study is part of the PR-LSAMP Dragonfly Project and abundance, distribution, and elevation data were obtained from its database. Five categories of elevation were made and the most representative species of each elevation were chosen to determine a relationship between abundance and elevation, through a Pearson correlation.
As a whole, Odonata was most diverse at lower elevations (0-230 m), with dragonflies as the dominant group. The most abundant species were Enallagma coecum and Erythrodiplax umbrata. Both species showed a tendency for decreasing in abundance with increasing elevation, but the relations were not significant (E. coecum: r = -0.79, p = 0.11; E. umbrata r = -0.77, p = 0.13). In conclusion, low elevations are important biodiversity areas for odonates. Our study suggests that the presence of appropriate habitats in lower and higher elevations could influence the abundance and diversity of these organisms, also the abiotic factors influence with respect to their elevation can interfere with the habitation of odonates.