Scarab beetle found on Pulau Ubin new to science

SINGAPORE – Research on the 1 sq km Chek Jawa Wetlands on Pulau Ubin has turned up a new species of scarab beetle that had not been found anywhere else in the world.

The Anomala sp. aff. matricula, which is part of a genus of beetle that includes more than 100 other species from Peninsular Malaysia and Sumatra, was uncovered during a survey of Pulau Ubin between 2018 and 2021.

The beetle is among over 1,300 native fauna species on the island recorded in a new online publication documenting the island’s natural heritage.

Titled An Update Of The Biodiversity In Pulau Ubin, the National Parks Board (NParks) publication gives details of more than 550 native flora species, and includes a compilation of findings of biodiversity surveys covering 11 taxonomic groups including vascular plants, moths, spiders and birds.

The publication was launched at the annual Ubin Day celebrations on June 20.

Minister of State for National Development Alvin Tan, who attended the event on the island, said it was significant as it is the first of its kind that comprehensively records Pulau Ubin’s biodiversity.

It documents two new species to science, including a species of spider – the Piranthus kohi – that was found in the secondary forest near the island’s coast.

The discovery was announced in 2020 as part of the Comprehensive Ubin Biodiversity Survey, which took place between 2018 and 2021.

The publication also documents 26 fauna species that are new to Singapore, such as the long-horned beetle, and the first record of the Ficus subulata in the country, a shrub that was found growing in several small patches of secondary forest on Pulau Ubin.

Said Tan: “The findings are also important because they include surveys that included several nationally critically endangered species, including the greater club rush, which had been presumed nationally extinct until its rediscovery in 2023, as well as the first Singapore record of the nationally critically endangered elegant fig.”

Speaking to The Straits Times, Cheong Loong Fah, an honorary research associate at NUS’ Lee Kong Chian Natural History Museum, who was involved in the discovery of the new species of scarab beetle, said it was unearthed during about 12 full days of surveying conducted over the span of three years on Pulau Ubin.

Although it was unlike anything he had seen before, Cheong could not be sure it was a new species.

Following consultation with an expert, he executed a genitalia dissection, which is a standard procedure that allowed the new species to be identified.

On the significance of the finding, Cheong said it showed that Singapore contains unimaginable biodiversity.

He also said with the number of insects declining drastically owing to factors like climate change, the discovery is a reminder to continue researching the role beetles play.

“They play a very important role in the whole functioning of the ecosystem. They are found in all kinds of microhabitats, so they play the role of pollinators, probably second to butterflies,” he said, adding that they also have a major role as decomposers.

NParks’ group director for conservation Lim Liang Jim said the discovery of the two unique species on Pulau Ubin showed there is still rich biodiversity in the country.

“The more you look in Singapore, the more things you will find. The richness of our biodiversity really plays up the fact that we are a city in nature,” he said, adding that the new publication can be beneficial to academics as a reference tool and for conservationists, to educate their work of protection and rejuvenation.

It can also be a basis for those in the field to engage the wider population to help them understand and appreciate the biodiversity.

Separately, Tan provided updates on the cryptic painted frog, a vulnerable nocturnal rainforest animal that was previously confined to the Bukit Timah and Central Catchment nature reserves and their surrounding nature parks.

He said following conservation efforts, the species is now showing encouraging signs that it is thriving and breeding naturally on Pulau Ubin.

Tadpoles were introduced at two sites on the island in June 2024 and March 2025, supported by artificial phytotelm habitats, which are water-filled cavities in large trees or fallen rotting logs.

Adult frogs were also moved from nature reserves on the mainland to Pulau Ubin in July 2025.

In August 2025, NParks observed four cryptic painted frog tadpoles and a clutch of eggs, indicating that the adult frogs from the introduced batch of tadpoles were adapting well to their new habitat and breeding successfully.

The first Ubin-bred cryptic painted frog was observed in October 2025, and NParks has since more than doubled the number of artificial phytotelms on the island to further support the population.

In April, a survey recorded a total of 31 tadpoles in the various phytotelms, up from 12 tadpoles in October 2025, offering an encouraging outlook for the species’ long-term survival.

“As an indicator of ecosystem health, the cryptic painted frog’s successful introduction on Pulau Ubin also provides valuable insights into the condition of the island’s habitats,” NParks said.