Introduction: The sand fly, Lutzomyia longipalpis, is the main vector of Leishmania infantum in the Americas, primarily occurring in areas of apparent anthropomorphic modifications in several regions of Brazil. Methods. Sand flies were captured using light traps. Results: Out of all captured species, Lu. longipalpis numbers had increased within the park. Conclusions: We report the occurrence of Lu. longipalpis in an area of Atlantic Forest, possibly representing the first sylvatic population of Lu. longipalpis in an area absent of peridomestic captures, but with the risk of L. infantum transmission in the areas of Niterói and Maricá.