With the exception of the exotic species Paraperipatus papuensis (Sedgwick, 1910) documented from Singapore Botanic Gardens in the 1960s (Van Der Lande, 1991), previous records of onychophora in Singapore include a single presumably native species that is restricted to old-growth forest in the Bukit Timah Nature Reserve (Murphy, 1973; Murphy et al., 2008) and mature secondary forest in the Central Catchment Nature Reserve (Court, 2012; Yeo, 2013). Although initially identified as ‘Eoperipatus sumatranus’ (see Murphy et al., 2008), this taxon has since been regarded as nomen dubium on the basis of a lack of type specimens and a conclusive type locality (Oliveira et al., 2012). Hence, despite its ‘endangered’ status locally (Murphy et al. 2008), the identity of Singapore’s native onychophoran species has yet to be reconciled. Although we are unable to identify the present animal, its discovery is nevertheless significant. It seems to be the first record of an onychophoran from Singapore’s offshore islands, and may also be the first account of these animals occurring in relatively young secondary forest in Singapore. The original natural vegetation on Pulau Ubin was cleared in the early 20th century to make way for granite quarries (Cornelius-Takahama, 2004). It is of interest to note that a whip spider, a whip scorpion, and the green tree snail (Amphidromus atricallosus temasek), uncommon invertebrates usually associated with forest habitats, have also showed up recently on Pulau Ubin (Ng, 2016; Tan & Xu, 2013). In addition to mature forests on Singapore Island, secondary forests on offshore islands may support populations of seemingly rare invertebrates as shown by the present record. Considering the very limited dispersal potential of velvet worms – a consequence of high habitat specificity and desiccation intolerance (McDonald & Daniels 2012) – it may be worth investigating the viability of potentially small, isolated populations on Singapore’s offshore islands.

Velvet worms appear to be rare and confined to forest habitats in Singapore. The native species was identified as Eoperipatus sumatranus, regarded as ‘endangered’ and thought to be confined to the Bukit Timah Nature Reserve (Murphy et al., 2008: 63). However, Oliveira et al. (2012) have regarded Eoperipatus sumatranus as a nomen dubium for which neither type specimens nor the type locality (although assumed to be Sumatra) are known.