No animal species are known to occur only within Singapore’s political borders.
Define “only found in Singapore” as a species whose entire global range is limited to Singapore alone. That means the species does not exist in Malaysia, Indonesia, or anywhere else. When you use this strict definition, no currently recognized animal species meet the test. Subspecies, very small populations, and poorly known invertebrates are different matters and may be locally unique, but they are not full species endemic to Singapore.
This empty result comes from geography and science. Singapore sits at the tip of the Malay Peninsula and shares most of its fauna with nearby mainland and island habitats. In the past, land connections and similar ecosystems let animals spread across the region. Taxonomy also changes: researchers sometimes split or lump populations, so a candidate “endemic” population can later be found to belong to a wider-ranging species. Finally, some tiny animals (insects, snails, freshwater crustaceans) are poorly surveyed and may be described later as new species, but at present none are documented as species found only in Singapore.
Look instead at close alternatives that interest nature lovers. Singapore does have locally distinct subspecies and highly restricted populations, rare invertebrates with tiny ranges, and plants that are truly endemic. You can also explore where to see regionally rare animals in places like Bukit Timah, Pulau Ubin, and Sungei Buloh, and read about conservation efforts for species that survive here but are rare elsewhere.
