On the natural occurrence of Poecilia reticulata Peters, 1859 (Cyprinodontiformes: Poeciliidae)
Corresponding author: Felipe Polivanov Ottoni, firstname.lastname@example.org
How to cite: de Bragança, P. H. N., Guimarães, E. C., de Brito, P. S., & Ottoni, F. P. (2020). On the natural occurrence of Poecilia reticulata Peters, 1859 (Cyprinodontiformes: Poeciliidae). Cybium, 44(4): 309-316. https://doi.org/10.26028/CYBIUM/2020-444-002
Despite many studies focusing on the invasive occurrence of Poecilia reticulata, the guppy, one of the most widely introduced freshwater fish species due to aquaria release and mosquito control, there are little and conflicting information about its natural distribution range. Based on extensive field surveys carried out in the Brazilian Amazon in the past ten years, information present in literature, online databases and museum records, P. reticulata is considered to be naturally absent from the Amazon Basin, from the Amapá and Pará territories in northern Brazil, and from French Guiana and Suriname. Poecilia reticulata records are few and noncontiguous for this entire region, generally associated with disturbed and polluted environments nearby populated areas. This pattern contrasts with a wider distribution expected by freshwater flooded savannah dwelling species, especially in the Guiana Shield coastal rivers, known for an ichthyofaunal similarity gradient pattern. The few records in the Amazon Basin are not attributed to low sampling effort but probably rather to the resilience and biotic resistance of pristine Amazonian habitat assemblages towards invasive species. The southernmost natural limit of P. reticulata distribution range was tentatively delimited as a region between the Essequibo River in the Guiana and the Orinoco Delta in Venezuela, where the species naturally occurs. Diagnostic characters distinguishing P. reticulata from close congeners that naturally occur in the region are presented.