The genus Topiris as revised in the paper. Credit: Mark Sterling, Trustees of NHMUK
Scientists at the Natural History Museum (NHM), London, have discovered that a long-overlooked moth specimen in the Museum's collection was in fact collected by explorer and naturalist, Alfred Russel Wallace, in 1855. This was at the same time as he was formulating his own revolutionary ideas on the origins of species that he would go on to share with Charles Darwin.
The small white moth, Topiris candidella, was described in 1863 by Francis Walker but was dismissed in 1927 by leading entomologist Edward Meyrick as "better neglected," having suffered substantial damage due to historical storing practices. The moth has remained overlooked for nearly a century, until now.
Using a cutting-edge DNA sequencing method, NHM scientists extracted genetic material from a single fragment of one of the specimen's remaining legs and connected it to a group of moths found throughout South East Asia.
The scientists were able to prove that rather than being a single neglected species, Topiris is in fact a genus of 14 species, including 11 species which are new to science. They are described in a paper in ZooKeys.
One of these species is named Topiris thunbergella, in honor of Greta Thunberg and her work in raising awareness of the environmental pressures on the native forests of South East Asia.
Dr. David Lees, Senior Curator for Microlepidoptera at the Natural History Museum, adds, "This discovery highlights the incredible potential of modern DNA analysis to reveal the evolutionary history of species, even from fragmented and long-forgotten specimens.
"By applying this innovative sequencing technique, we have not only revived Francis Walker's species Topiris candidella, from 1863, but also expanded our understanding of an entire group of small white moths."
During their research, Lees and fellow moth expert, Mark Sterling, found that a hidden label under the pin of the broken moth bore the handwritten letters "SAR," a clue that this moth had been collected by Wallace as part of over a thousand moths he collected at Rajah Brooke's Forest retreat.
This was in December 1855, just months before he published his "Sarawak Law" paper, which eventually led to a joint reading (at Darwin's request) of their theories of evolution through natural selection.
Beyond the scientific breakthrough, the study has wider conservation implications. Of the 24 species reviewed in their paper, only three have been recorded since 2000, highlighting the urgent need for biodiversity monitoring in this region.
Sterling added, "The 80 million specimens currently held in the Natural History Museum's collections continue to be a critical resource for understanding biodiversity and assessing the effects of environmental change."
More information: Mark J. Sterling et al, A revision of the hitherto neglected genus Topiris Walker, 1863 (Lepidoptera, Xyloryctidae) with taxonomic notes on the genus Athrypsiastis Meyrick, 1910, ZooKeys (2025).
Journal information: ZooKeys
Provided by Natural History Museum
This story is republished courtesy of Natural History Museum. Read the original story