In 2018, I wrote about an unknown wild Dioscorea species (Fig. 1) after collecting two bulbils from it to grow in my pot. I posted a brief update on its germination in March 2019. The species remains unidentified.

(a) Top of leaf	(b) Underside of leaf	(c) Stem and leaf stalk	(d) Growing tip
Fig. 1 (a-d): Unknown wild Dioscorea species

This month, I noticed that the bottom of one of my pots had partially given way. A tuber from this climber had grown through the gap beneath the pot and broken off. Using the available specimen, I dissected the tuber to examine its interior (Fig. 2). There are no bulbils on the climber at present; they appear only on drooping stems, which are currently absent.

Fig. 2: Tuber of unknown wild Dioscorea species

With the latest Singapore Flora Checklist published in 2022, it is timely to revisit the status of the genus Dioscorea in Singapore. The checklist records 10 Dioscorea species (Table 1). Although Dioscorea prainiana is listed as NEx (Nationally extinct), an observation was reported in Singapore on iNaturalist on 25 May 2024. Based on iNaturalist observation counts for the 10 Singapore Dioscorea species (Table 1) accessed on 16 August 2026, the most frequently recorded species is Dioscorea sansibarensis, commonly known as Zanzibar Yam or Batman Plant. It is a naturalised species regarded as a problematic invasive species in our rainforests.

After browsing images on the Dioscorea species pages on iNaturalist, I found two possible candidates for my unknown Dioscorea: Dioscorea fordii and Dioscorea belophylla. However, they occur mainly in Hong Kong and the Indian subcontinent, respectively, so this potential identification remains a long shot.

Nevertheless, the unknown Dioscorea species continues to grow well in my pot. Its tubers, hidden in the soil, have repeatedly sprouted new climbers despite my clearing the plants from the pot several times over the years. Hopefully, I will identify it one day.