At the recently concluded Festival of Biodiversity, visitors discovered lots of interesting and unique species that were either found only in Singapore, discovered in Singapore, named after Singapore or had special links to Singapore.

The exhibition after all was themed “Celebrating SG50: Our Natural Heritage”. Despite being a small island with a total land area of 716 sq km, Singapore is home to a surprising amount of biodiversity. Throughout Singapore, we have a staggering 2,145 species of native vascular plants, 65 species of mammals, 384 species of birds, 317 species of butterflies and many more. Here are just a few of the fascinating species closely linked to Singapore.

Johnson’s Freshwater Crab, Singapore Freshwater Crab, Singapore Swamp Forest Crab (Irmengardia johnsoni, Johora singaporensis, Parathelphusa reticulata)
Singapore is home to three endemic freshwater crabs, Johnson’s Freshwater Crab, the Singapore Freshwater Crab, and the Singapore Swamp Forest Crab. These crabs are restricted to the freshwater streams of Singapore, making them among the rarest crabs in the world.

The Singapore Freshwater Crab has been identified as one of the top 100 most threatened species in the world. All three crabs are primarily scavengers that feed on coarse organic matter such as dead leaves. However, they are also opportunistic predators, eating small animals when available. These crabs perform key roles in their freshwater stream habitats by promoting the recycling of nutrients. These crustaceans act as important indicators for pollution and climate change as they are sensitive to changes in their habitats.

The Johnson’s Freshwater Crab is usually found in slower parts of shaded streams with leaf-litter.

The Singapore Freshwater Crab is associated with well-oxygenated hill streams.

The Singapore Swamp Forest Crab prefers slow-flowing acidic streams with leaf litter and low oxygen levels.

Long-tailed Macaque (Macaca Fascicularis)
The Long-tailed Macaque was described by Raffles in 1821, two years after he founded Singapore! These monkeys are common in many of our wild shores and nature reserves.  They feed on a variety of fruits, leaves, tiny mammals, birds, crustaceans - including shellfish and crabs, and discarded leftovers from visitors. The highly adaptive macaque is the most successful non-human primate in Southeast Asia.

Singapore Kopsia (Kopsia Singapurensis)
The Singapore Kopsia is a small tree that grows in freshwater swamp forests. It can only be found in Singapore and Peninsular Malaysia. The flower, with its white petals and red heart, is reminiscent of the Singapore national flag. In the wild, the plant flowers twice a year. When cultivated under the right conditions, it can be free flowering.

Tembusu (Cyrtophyllum fragrans)
If this species looks familiar to you, it might be because the five-dollar note features a Tembusu tree! The particular individual featured on the note is a Heritage Tree located at the Singapore Botanic Gardens that is believed to be nearly 200 years old. This species is recognised  by its stately form and deeply fissured bark. It produces creamy-white flowers that open at sunset and give off a sweet perfume.

Money Cowrie (Monetaria moneta)
The Money Cowrie earns its name from the widespread use of its shell as currency in many Pacific and Indian Ocean countries before coins were invented. This species of cowrie is herbivorous, grazing on algae in intertidal habitats. Today, the Money Cowrie is featured on the background of the two-dollar note.

Gelam Tree (Melaleuca cajuputi)
Kampong Glam derives its name from the Gelam tree, which used to be found in the area. In the 19th century, Kampong Glam was home to the Sultan of Singapore, as well as a settlement for Arab and Malay communities.

Gelam Tree

The tree has a distinct peeling and papery bark, and its crushed leaves emit a fragrant scent. It is also a source of cajuput oil, which is used for making Tiger Balm ointment.

Text by Zhou Boyi
Photos of crabs by Cai Yixiong
Photo of Long-tailed Macaque by Jayasri
Photos of Singapore Kopsia and Gelam Tree by Ang Wee Foong
Photo of Money Cowrie by Ron Yeo