115 new species of fungus gnats discovered in Singapore; researchers name some after notable women

SINGAPORE – Fungus gnats, tiny insects measuring just millimetres long, may have previously flown under the radar – but gnat any more. 

A new study published on Dec 30 has uncovered 120 species of these fungus-loving insects in Singapore. 

This is the first time the fungus gnat diversity in Singapore has been mapped out, as no species of fungus gnats were officially recorded from here previously. 

Of the 120 species identified in the study, 115 are new to science, which means they had also previously been unknown to the rest of the world. 

Thirty-one of them have been named after women inducted into the Singapore Women’s Hall of Fame, in an effort by the researchers involved in the study to honour the contributions of these women and to right the “longstanding gender imbalances in scientific naming”. 

Some families of fungus gnats are considered by gardening enthusiasts to be pests as they are known to infest potted plants. But other groups of these forest-dwelling creatures very likely play important roles in maintaining the forest ecosystem; how they specifically contribute remains to be determined by further studies. 

Insect researcher Ang Yuchen from the National University of Singapore (NUS) Lee Kong Chien Natural History Museum, who was involved in the latest study, said that as these insects feed on and move between fungal patches, they likely influence fungal community balance – the basic machinery that keeps forests running.

“The key point is that their tight association and the sheer diversity of species strongly suggest they’re an important part of fungal-driven forest processes, even though the precise roles of most tropical species still aren’t fully quantified,” said Dr Ang, who is the senior curator of insects at the museum. 

Their role in the ecosystem warrants further investigation, he added, which is why building a baseline is important.

Dr Ang added that knowing what fungus gnats can be found in Singapore and where is vital for conservation planning. “If we find that a species is only found in a particular habitat, any planned development would need to consider the fate of the species,” he said. 

“Development for Singapore’s continued well-being and survival must come foremost, but with this information, we can make better informed choices and mitigating actions to help conserve our natural heritage,” he added. 

The study began in 2012, when museum researchers collaborated with researchers from Brazil, Germany and Norway to attempt to identify fungus gnat species in Singapore. Collaborators included Professor Dalton de Souza Amorim of the University of Sao Paulo, a global expert on flies, particularly fungus gnats. 

When asked why the research group chose to focus on this group of insects, Dr Ang noted that fungus gnats are poorly studied despite being an abundant and species-rich group due to their small size. 

The conventional method of differentiating species required individual inspection of these tiny organisms, and expert knowledge of the subtle variations in organism characteristics, he added. But the advent of new, scalable scientific methods, such as DNA barcoding which allows specimens to be sorted by their genetic material, helped speed things up, Dr Ang said. 

For the study, insect traps were set up in a range of habitats, including mangroves, swamp forests, primary and secondary forests, as well as urban green spaces. A total of 1,454 specimens of fungus gnats were analysed.

The team then sorted the specimens by identifying short pieces of DNA “barcodes” unique to each species, similar to scanning a product’s barcode at the supermarket. 

Such large-scale automated sorting puts the specimens into different species “piles”.  

Within each “pile”, the specimens are then verified in the traditional way of identifying insects by examining key body features. 

“This project is at the front-edge in finding solutions for studying highly diverse and poorly known insect groups,” said Prof Amorim.

Dr Ang said the discovery of the new species suggests that Singapore is able to support a wider diversity of insect species than previously known. 

“Singapore is located in a biodiversity-rich zone with one of the highest rates of endemism (species found only within a specific geographic area) due to our archipelago of islands,” said Dr Ang. “So even in habitats that have suffered development and redevelopment, we are finding a lot of new species.”

On naming some of the new species after notable women in Singapore, Prof Amorim said: “We wanted to tell a bit of Singapore’s story through these names and to honour individuals whose contributions to modern Singaporean society the team felt deserved greater visibility.” The Mycetophila georgettechenae, for instance, was named after renowned Singaporean painter Georgette Chen, while Integricypta shirinae was named after women’s rights activist Shirin Fozdar. 

Dr Ang added: “Historically, many species tend to be named after men. This approach is intended as a modest step towards greater gender parity.”

Besides fungus gnats, Dr Ang said he is also working on identifying other groups of flies, such as the long-legged flies which are useful bioindicators for forest and mangrove habitats.

Through his work, he hopes to establish a Singapore Total Arthropod Biodiversity Baseline, which he believes to be important for ecosystem monitoring. Arthropods refer to invertebrates or animals without a backbone, such as insects.

As this study becomes a launchpad for follow-on work on other understudied insects, Dr Ang said he hopes to continue shedding light on the local biodiversity hidden in plain sight. “As I always like to say, ‘Throw a stone in the wild and you’d likely hit an undescribed species.’”

New critters discovered in Singapore

Mycetophila georgettechenae 

Aspidionia janetjesudasonae 

Integricypta shirinae