European regional assessment: Least Concern (LC)
EU 27 regional assessment: Least Concern (LC)

This is a Tyrrhenian endemic species, distributed from the southern coast of mainland France along scattered Ligurian and Tyrrhenian coastal regions, Corsica, Sardinia, and numerous islands and islets. It is assessed as Least Concern for Europe and the EU27 Member States because its extent of occurrence is over 120,000 km², and although it occurs in a number of small, widely separated subpopulations and may be at localised risk on the larger islands within its range there is no clear evidence of widespread decline.

Euleptes europaea is a Tyrrhenian endemic species, it is found on the Mediterranean islands of Corsica (France) and Sardinia (Italy) and on 81 circum-Corsican islands (Delaugerre and Corti 2020) and 95 circum-Sardinian islands (Corti et al. 2022), as well as on a number of smaller offshore islands of France (Port-Cros and Le Levant in the Iles d'Hyeres, nine small islands near Marseilles), it is also found in scattered localities of the coastal zones of the Alpes-Maritimes (France) (Renet et al. 2013); in mainland Italy Euleptes inhabits a few coastal localities in Tuscany and Liguria (including Monte Argentario, Piombino and Genoa), recently it was discovered in Positano, Campania. The species also inhabits the Tuscan Archipelago (Capraia, Elba, Cerboli, Pianosa, Montecristo, Giglio, Giannutri islands as well as several islets) and other minor Tuscan coastal islets (Corti et al. 2006, 2022); Euleptes may also be present on Gorgona, but it has not yet been observed there; M.J. Delaugerre pers. comm. October 2022). It can be found up to 1,550 m asl but is less common at higher elevations. It is generally most common in suitable rocky habitats however with a preference for low elevations (0-1300 m asl. Delaugerre 1984, Delaugerre and Cheylan 1992).

Out of the European region, 19th Century records exist for islands off the Tunisian coast. Delaugerre et al. (2011) confirmed the presence of extant Tunisian subpopulations on La Fauchelle (= Aguglia) and several islets in the Galita Archipelago. These records suggest it once occurred on the main island of Galita, for which it has never been confirmed, and being therefore extinct as for Galitone Islet and Cani islets (Delaugerre et al. 2011).

The species can be relatively abundant within suitable habitats. High densities of this gecko can be found on some islands, with aggregations of dozens of individuals in less than a square metre where "roomy" cracks are present (Delaugerre and Corti 2020). Genetic data show high density and population structure in the centre of south Sardinia (Salvi et al. 2018). It is less frequently observed in human buildings than other European geckos. It appears to be resistant to inbreeding and has persisted in subpopulations of only a "few dozen" individuals for thousands of generations (Delaugerre and Corti 2020).

Extinctions have been recorded for islands at the northern and southern limits of its range (Delaugerre et al. 2011). Several drastic declines have been recorded in several northern islands of Provence (Pomègues and Ratonneau, Grand and Petit Congloué, If), (summarized in Delaugerre and Corti 2020). The very first documented extinction occurred on an Italian island has been documented for La Scarpa Islet (Tuscan Archipelago) (Corti et al. 2022). A decline has been observed in some coastal localities in northern Sardinia (D. Salvi pers. comm. October 2022). In the first intensive survey of these areas (2005) high density was observed, but few to zero were observed in follow-up surveys in 2012 and 2022 (D. Salvi pers. comm. 2022).

Conversely, population recovery has been reported on some islands (Grand, Petit Congloué, Pomègue and Ratonneau; Delaugerre and Corti 2020) following rat eradication in 2000 for the two Congloué islets (Salvidio and Delaugerre 2003). The species had previously been considered extinct on both islands for more than a century, suggesting that where it reaches very low population densities it can be extremely cryptic (Delaugerre et al. 2011). Mainland subpopulations and those of larger islands are more sensitive to these impacts, but the species tends to higher population density on small islands and the overall population trend is unknown. It might be more common than known because it is easily overlooked.

This strictly nocturnal gecko is generally found in rocky areas, such as cliffs, boulders, and stone walls in agricultural land. It prefers areas with somewhat humid refugia, and thermoregulates within crevices and never openly basks (Salvidio et al. 2010). Its arboreal microhabitats have been overlooked (Delaugerre et al. in press; Deso et al. in press). It largely avoids areas of maquis vegetation, woodland and urban environments (although it may be encountered in abandoned buildings) (Salvidio et al. 2010).

The gecko is able to persist on very small islands compared to other insular reptiles in the range, and appears to be able to persist as a viable subpopulation in very simple systems with only a few hundred grams of biomass (Delaugerre and Corti 2020).

It can be active for 8-10 months in the year (Sindaco et al. 2010). The females lay two to three clutches of two eggs annually.

In Corsica and Sardinia, it is locally threatened by habitat loss resulting from fires and urbanisation. It is nevertheless widespread in Sardinia, Corsica and in the Tuscan Archipelago where only one subpopulation has been lost (Delaugerre et al. 2011, Corti et al 2022). The subpopulation of mainland Italy in Genoa, and the subpopulations of mainland French, are likely threatened, and subpopulation losses have been recorded in Liguria (Delaugerre et al. 2011). Nine island extinctions have been documented across the range, three on small islands and six on larger islands at the northern and southern limits of the species range (Delaugerre et al. 2011, Corti et al. 2022). The decline has been observed in some coastal subpopulations of northern Sardinia (D. Salvi pers. comm. 2022). The hypothesised drivers are plastering of walls and buildings, which removes the cracks on which this species depends for refuge, and perhaps competitive displacement because of the gecko Tarentola mauritanica (D. Salvi pers. comm. 2022). This latter is speculative, since the two species co-occur in many sites there is currently no evidence that this species poses a threat to Euleptes (D. Salvi pers. comm. 2022). These islands are characterised by human settlements and/or the presence of invasive ship rats and 50% of them have been colonised by another gecko species (Delaugerre et al. 2011).

Only 50 of the 311 islands within the range of this species have a permanent human presence and on most islands where the lizard occurs, there is limited anthropogenic disturbance of the habitat (Delaugerre et al. 2011). Interactions with the ship rats have been studied on 30 islands across its range (Delaugerre et al. 2011), however the lizard has coexisted with this species on most islands, in some cases for up to 2,400 years. Although larger geckos are scarce on these islands and Euleptes shift their spatial behaviour by avoiding open rock faces in islands where rats are present, there is no evidence of a decline in body condition (Delaugerre et al. 2019). Rabbits, cats, non-native geckos, and invasive plants have also been introduced over a similar time frame. The population of the Yellow-legged Gull (Larus michaellis) increased during the second half of the 20th Century, which likely impacted the ecosystems of the islands (Delaugerre et al. 2011).

There are no known threats to subpopulations on the islands off Tunisia. Lighthouses have been built on the two islands where E. europaea extinction has been documented (Delaugerre et al. 2011). The human commensal gecko, Hemidactylus turcicus is at present established on both islands and Delaugerre et al. (2011) suggest that the arrival of Hemidactylus was most likely the driver of the extinction of Euleptes, probably not because of predation or competition but most likely by pathogens carried by the non-native gecko, moreover, Delaugerre and Corti (2020) note that the two species co-occur in many localities of the European Leaf-toed Gecko's range even on the tiny Toro island (SW Sardinia) where Euleptes prevails.

There is no significant use of or trade in this species.

This species is listed on Appendix II of the Bern Convention and Annex IV of the EU Habitats Directive. It occurs in many natural protected areas (e.g. national Parks, nature reserves) in France and in Italy. Population monitoring has been trialled using artificial refugia, which geckos appear to rapidly colonise, and Cheylan et al. (2018) recommend adopting this approach to monitoring declines and recoveries on islands where this species is of conservation interest.