BioInvasions Records

Introduction

The Caribbean region is emerging as a hotspot for the spread of non-native reptile species (Powell et al. 2011; Powell and Henderson 2012). Two lizard groups, anoles (species from the genus Anolis) and geckos (species from the infraorder Gekkota), are among the most prominent of introduced reptiles on Caribbean islands (Helmus et al. 2014; Perella and Behm 2020). Anole and gecko species are frequently introduced accidentally through the live plant trade, but may also be introduced intentionally as pets (Kraus 2009). The Caribbean region is also a reptile biodiversity hotspot and most islands have unique endemic anole and gecko species (Myers et al. 2000; Hedges 2011). Therefore, identifying newly introduced gecko and anole species, including their introduction pathways and ecological impacts, is a conservation priority.

Aruba has 10 previously recorded introductions of non-native reptile species, including two anoles, Anolis sagrei (Duméril & Bibron, 1837) and A. porcatus (Gray, 1840), and four geckos, Gonatodes albogularis (Duméril & Bibron, 1836), G. antillensis (Lidth de Jeude, 1887), G. vittatus (Lichtenstein & Martens, 1856), and Hemidactylus mabouia (Moreau de Jonnès 1818), making it one of the most invaded islands in the Caribbean (van Buurt 2005, 2011). Aruba is also one of the most economically connected islands in the region which likely explains the high rate of introductions (Powell et al. 2011; Helmus et al. 2014). Interestingly, unlike most Caribbean islands, the natural habitat in Aruba is quite arid and may be difficult for species to invade if they are not adapted to those conditions. Many of the non-native species may be using anthropogenic habitat that receives irrigation subsidies. Given the high rate of introductions and harsh natural conditions, we searched anthropogenic habitat on Aruba for non-native reptile species. Here, we report the first observations of two new non-native anole and one non-native gecko species on Aruba. In addition, we report a range expansion of a non-native anole species that was previously observed at only one location on Aruba. To better understand the context and potential impacts of the four introduced species we documented on Aruba, we compiled information from the literature regarding the timing, introduction pathway, and ecological impacts of those four species in their introduced ranges within the Caribbean region.

Abstract

The Caribbean islands are becoming a hotspot for the spread of non-native reptiles. Consistent with this trend, we provide the first documentation of three new lizard species discovered on Aruba, Anolis gingivinus (Cope, 1864), Anolis cristatellus (Duméril and Bibron, 1837), and Hemidactylus frenatus (Duméril and Bibron, 1836). In addition, we provide an updated distribution on Aruba for a previously introduced lizard species, Anolis porcatus (Gray, 1840). All four species were identified phenotypically in the field and identifications were confirmed with genetics. Like most non-native lizards in the Caribbean, they tend to use anthropogenic habitats, and their impacts on Aruba’s resident species are not known.

and remarks on their Caribbean distributions

Abstract

Globally, geckos (Gekkonidae) are one of the most successful reptile families for exotic species. With the exception of the widespread invader, Hemidactylus mabouia, however, introductions of exotic gecko species are a more recent occurrence in the Caribbean islands despite extensive introductions of exotic geckos in the surrounding Caribbean region. Here we report three new exotic gecko species establishments on the mid-sized Caribbean island of Curaçao (Leeward Antilles). Of the three new exotic species, the mourning gecko, Lepidodactylus lugubris (Duméril and Bibron, 1836) has the largest distribution on Curaçao and has likely been established for the longest time. The common house gecko, Hemidactylus frenatus (in Duméril, 1836) has a limited distribution and was likely a more recent introduction. Finally, the Tokay gecko, Gekko gecko (Linnaeus, 1758), escaped from captivity and is known from a single locality. Both L. lugubris and H. frenatus have had widespread distributions in the greater Caribbean region for over 70 years yet have only been reported from Caribbean islands within the past decade. Comparatively, the scope of G. gecko introductions on Caribbean islands is similar to L. lugubris and H. frenatus but introduced populations of G. gecko in the greater Caribbean region are virtually absent. These patterns indicate that different introduction pathways (intentional vs passive) may affect the size of exotic geographic ranges, and that the rate of exotic gecko introductions to Caribbean islands may now be increasing.

Key words: invasion, Lesser Antilles, lizard, neotropics, non-native, parthenogenic species, Sauria

Globally, geckos (Gekkonidae) are one of the most successful reptile families for exotic species. With the exception of the widespread invader, Hemidactylus mabouia, however, introductions of exotic gecko species are a more recent occurrence in the Caribbean islands despite extensive introductions of exotic geckos in the surrounding Caribbean region. Here we report three new exotic gecko species establishments on the mid-sized Caribbean island of Curaçao (Leeward Antilles). Of the three new exotic species, the mourning gecko, Lepidodactylus lugubris (Duméril and Bibron, 1836) has the largest distribution on Curaçao and has likely been established for the longest time. The common house gecko, Hemidactylus frenatus (in Duméril, 1836) has a limited distribution and was likely a more recent introduction. Finally, the Tokay gecko, Gekko gecko (Linnaeus, 1758), escaped from captivity and is known from a single locality. Both L. lugubris and H. frenatus have had widespread distributions in the greater Caribbean region for over 70 years yet have only been reported from Caribbean islands within the past decade. Comparatively, the scope of G. gecko introductions on Caribbean islands is similar to L. lugubris and H. frenatusbut introduced populations of G. gecko in the greater Caribbean region are virtually absent. These patterns indicate that different introduction pathways (intentional vs passive) may affect the size of exotic geographic ranges, and that the rate of exotic gecko introductions to Caribbean islands may now be increasing.