caribbean herpetology

Within the northern Lesser Antilles, the island of Saint Martin, including the Dutch part (St. Maarten, a constituent country of The Netherlands) and the French part (the Collectivity of Saint Martin), is considered the main hub for established non-native reptiles, currently numbering ten species (Table 1) (Dewynter et al. 2022; Thorpe 2022). The islands of Saba and St. Eustatius are special municipalities of The Netherlands and frequently trade with St. Maarten. During the last five years, several new non-native reptile species have been reported on Saba and St. Eustatius, which originate from the non-native populations already present on Saint Martin: the Green Iguana, Iguana iguana (van den Burg et al. 2018, 2022) on St. Eustatius, and the Brahminy Blindsnake, Indotyphlops braminus (van den Burg et al. 2021) and Smooth-scaled Tegulet, Gymnophthalmus underwoodi on Saba (van den Burg et al. 2021). It is believed that these newly established populations have been facilitated by poor biosecurity between the islands. Here, we describe the establishment of two species, G. underwoodi and the Common House Gecko, Hemidactylus frenatus, on St. Eustatius.

On the 14th of December, 2020, an individual of Lepidodactylus lugubris was found and photographed in Bonaire (Dutch Caribbean) by Hans Smulders in a garden at the following address: Sabadeco Shores 28 (12.198174, -68.302846), 16 m elevation. The animal was found around some potted plants. This species has not been reported previously from Bonaire (Behm et al. 2019).

The native herpetofauna of the Lesser Antillean island of Saba (13 km2; 17.63°N, -63.24°W) includes one snake, Alsophis rufiventris, and four species of lizards, Anolis sabanus, Iguana melanoderma, Sphaerodactylus sabanus, and Thecadatylus rapicauda (Powell et al. 2015). Here, we report the establishment of both Gymnophthalmus underwoo-di Grant, 1958 and Indotyphlops braminus (Daudin, 1803) on the island.

The Leeward Blindsnake (Antillotyphlops geotomus) is a near threatened species according to the IUCN Red list (Powell et al., 2016), and was known only to occur on Antigua, Barbuda, St. Kitts, and Nevis, where it is considered a native species (Thomas 1966). Here we report the discovery of A. geotomus on St. Eustatius, Caribbean Netherlands. We obtained a DNA sequence of the mitochondrial 16S rRNA gene from a specimen collected on St. Eustatius in 2018 using the primers 16Sar (5’-CGCCTGTTTATCAAAAACAT-3’) and 16Sbr (5’-CCGGTCTGAACTCAGATCACGT-3’) (Palumbi 1996). The sequence was deposited in Genbank (MT256921). Blast analysis of the sequence resulted in 100% and 99.8% identity to sequences in Genbank of A. geotomus from Nevis (KF993199) and Antigua (AF366789) respectively. A 98.5% identity match was found with its nearest relative Antillotyphlops monastus (AF366708, KF993209). This species identification (A. geotomus) is consistent with the absence of pigment on the underside of the tail, a diagnostic trait of A. geotomus compared with A. monastus (Thomas 1966). The collected specimen had a total length of 125 mm, although they are known to reach lengths of up to 213 mm (Hedges et al. 2014). Furthermore, St. Eustatius is geographically in close proximity to St. Kitts & Nevis, which lie on the same shallow submarine bank only to be separated by the sea after the last ice age. Therefore, A. geotomus is likely native to St. Eustatius and not introduced. The other snake known from the island is the Red-bellied Racer (Alsophis rufiventris, native).