Panisi, M. & de Lima, R.F. (2022) Disease implicated in decline of the threatened Obô Giant Land Snail Archachatina bicarinata in São Tomé and Príncipe. Tentacle, 30, 19-21.
The rapid decline of the Obô giant land snail Archachatina bicarinata (Bruguière, 1792; Fig. 1) has long been identified (Gascoigne, 1994; Dallimer & Melo, 2010; Panisi et al., 2020) in the oceanic islands of Príncipe and São Tomé (Democratic Republic of São Tomé and Príncipe, Central Africa), where it is endemic. The species was abundant and widespread until the mid-20th century, but it is now restricted to the most remote forests of both islands (Panisi et al., in press). Overharvesting, habitat loss and the introduction of the West African giant land snail Archachatina marginata (Swainson, 1821; Fig.1) are all possible causes for its decline, and a potential disease has also been implicated since 1994 (Gascoigne, 1994; Panisi et al., in press). The Obô giant land snail is listed by IUCN (Clarke & Naggs, 1996) as “Vulnerable” but a new assessment suggests an upgrade to “Endangered”. The suspicion around an unidentified disease is particularly concerning, as it would have the potential to push it towards extinctions in the near future.