The invasive twospot livebearer's biology, and its current and potential global distribution

Abstract

Poeciliids are widely recognized as successful invaders, possessing traits associated with invasion success. Native to Central America and south‐eastern Mexico, the twospot livebearer (Pseudoxiphophorus bimaculatus) is a species recently recognized as invasive in both Central and northern Mexico. Despite its invasive status, limited research exists on its invasion process and the potential threats it poses to native species. In this study, we conducted a comprehensive review of the current knowledge on the twospot livebearer and mapped its current and potential distribution worldwide. The twospot livebearer shares similar traits with other successful invaders within the same family. Notably, it exhibits high fecundity throughout the year and demonstrates resilience to highly polluted and oxygen‐deprived water conditions. This fish serves as a host for several parasites, including generalists, and has been extensively translocated for commercial purposes. Recently, it has also been used for biocontrol within its native range. Apart from existing outside its native range, the twospot livebearer, under current climate conditions and if transported there, could readily colonize biodiversity hotspots in tropical zones worldwide, including the Caribbean Islands, the Horn of Africa, North of Madagascar Island, south‐eastern Brazil, and others located in southern and eastern Asia. Given that this fish is highly plastic and our Species Distribution Model, we consider that all areas with a habitat suitability >0.2 should prevent its arrival and establishment. Our findings underscore the urgent need to recognize this species as a threat to freshwater native topminnows and prevent its introduction and spread.

Heterospecific sociability and foraging behaviour of an invasive livebearer fish

“…The twospot livebearer (Pseudoxiphophorus bimaculatus) is an omnivorous poecilid native to southern Mexico, Nicaragua, Guatemala, Belize and Honduras (Lyons, 2019) that can reach a standard length (SL) of 66 mm (Mar-Silva et al, 2021). The twospot livebearer was recently recognised as an invasive fish species present on the Mexican Central Plateau (MCP) (Gomez-Maldonado et al, 2023). To date, only one study has been published on the behaviour of this fish species, which focused on the species' ability to recognise conspecifics and heterospecifics (Basolo, 2002;Gomez-Maldonado et al, 2023).…”

“…The twospot livebearer was recently recognised as an invasive fish species present on the Mexican Central Plateau (MCP) (Gomez-Maldonado et al, 2023). To date, only one study has been published on the behaviour of this fish species, which focused on the species' ability to recognise conspecifics and heterospecifics (Basolo, 2002;Gomez-Maldonado et al, 2023).…”