New species of firefly found in Singapore’s last freshwater swamp forest
A team of researchers from NUS and National Parks Board (NParks) has discovered a new species of firefly from Nee Soon Swamp Forest, the last remaining freshwater swamp forest in Singapore. This is the first time since 1909 that a new species of luminous firefly has been discovered in the city-state.
The research on the newly-identified Singapore firefly (Luciola singapura) was first published in the journal Animals on 4 March 2021.
“When we first encountered this species, we knew it was interesting because the specimens were collected from a freshwater swamp forest in the central catchment area of Singapore—fireflies are rarely reported from this type of habitat. Furthermore, it did not fit the descriptions of any known firefly species to-date,” said lead author Dr Wan Faridah Akmal Jusoh, a Research Fellow at the NUS Lee Kong Chian Natural History Museum (LKCNHM).
In 2009, a nationwide survey of fireflies by NParks at 14 sites across Singapore documented 11 firefly species, including an unidentified species, codenamed Luciola sp. 2 after the firefly genus Luciola.
“We thought the specimens collected in 2009 were the only ones of the unidentified species until I started examining the firefly collection in LKCNHM, and found three additional specimens collected 10 years prior. I immediately contacted my colleagues at NParks and we arranged a series of night surveys,” explained Dr Jusoh.
A decade after the 2009 nationwide survey, the researchers from NUS and NParks revisited the firefly habitat located in the Nee Soon Swamp Forest and successfully collected additional specimens of Luciola sp. 2.
The challenge of identifying a new species
The genus Luciola contains at least 280 species, most of which cannot be readily distinguished from one another by eye. Therefore, to determine the identity of Luciola sp. 2, the researchers performed intricate dissections to examine internal organs and employed modern DNA techniques through a method called “genome skimming”.
After two years of data collection and analysis, which was conducted in collaboration with researchers from Charles Sturt University, Forest Research Institute Malaysia, and NUS Biological Sciences, the team showed that Luciola sp. 2 was both genetically and morphologically unique. The species, which is less than 5 millimetres long, was described as a new species called Luciola singapura.
“This study underscores the importance and utility of molecular methods that can provide solutions to problems that are otherwise difficult to resolve using traditional approaches,” stated LKCNHM Museum Officer Dr Chan Kin Onn, who is one of the co-authors of the research.
First new Singaporean firefly species in over a century
This discovery comes more than a century after the last species of luminous firefly was found in Singapore, and gives hope that continued research and advancements in molecular techniques can help further understand Singapore’s natural heritage.
The last luminous firefly described from Singapore was Pteroptyx bearni Olivier in 1909, which is a well-known congregating firefly species in Southeast Asian mangroves. Unfortunately, this species has not been sighted in Singapore since that time, and is assumed to have been eradicated.
Lim Liang Jim, Group Director of the National Biodiversity Centre at NParks added, “The discovery of this new species is very significant to science in Singapore, and shows the importance of conserving the last freshwater swamp forest here. As part of efforts to transform Singapore into a City in Nature, under the NParks Nature Conservation Masterplan, we are implementing species recovery plans for our endangered and rare species which include enhancing core habitats. We currently have a species recovery plan for Singapore fireflies and this new discovery will also contribute to the understanding of the species and ecology of fireflies in Singapore.”