WASHINGTON, DC.- Scientists led by the Smithsonian’s National Museum of Natural History have restored the physical reference of one of the most historically significant names in biology. In a paper published today in Taxonomy, researchers designated a new type specimen, or neotype, for Araneus angulatus, the first animal species described using binomial nomenclature, the two-part naming system that scientists use today to identify and classify living organisms. The designation reconnects the name to a physical specimen decades after the original name-bearing spiders disappeared.

The button-size spider Araneus angulatus was originally described in 1757 by Swedish arachnologist Carl Alexander Clerck. To support his description, Clerck preserved three A. angulatus spiders that served as “types,” specimens that define what a species name refers to. But sometime between 1858 and 1965, those scientifically invaluable specimens vanished.

“That meant that the scientific name Araneus angulatus was suddenly unmoored from reality,” said arachnologist Jonathan Coddington, an emeritus researcher and curator at the museum. “There was no specimen to show exactly what this name actually means.”

To restore that missing connection, Coddington and an international team examined newly collected A. angulatus specimens from Sweden near where Clerck is believed to have collected the original types. After comparing the spiders to Clerck's descriptions and illustrations and confirming their identity through DNA analysis, the researchers designated one specimen as the new neotype, establishing an official physical reference for the species for the first time in at least six decades.

The research began as a passion project for Coddington, who has described many new species of spiders over his 40-year career at the museum. It quickly turned into an international research effort that he found reminiscent of a historical thriller in the vein of the Da Vinci Code.

“This science spans centuries, involves major historical figures and culminates with a scientist going out to an island in the middle of the Baltic Sea to catch eight spiders,” he said.

The central figure in this historical saga is Clerck, who was a government official in Stockholm. In the 1730s, he became fascinated with taxonomy, the branch of science focused on classifying organisms, after attending a lecture by Carl Linnaeus, an eminent Swedish biologist who invented binomial nomenclature. Before Linnaeus, species names were long amalgamations of descriptive words that often varied from place to place. Linnaeus aimed to standardize the naming process by using only a generic name to describe an organism’s group, or genus, and a specific name to describe that organism’s particular species within the genus. This convention created streamlined scientific names like Homo sapiens.

In 1753, Linnaeus used binomial nomenclature to classify species of plants but had yet to apply the naming convention to animals. Then, in 1757, Clerck published his opus on Swedish spiders, Svenska Spindlar. The book, which included Clerck’s illustrations, described 66 species beginning with A. angulatus. Linnaeus later used some of Clerck’s spider names in the 10th edition of his book Systema Naturae, which was published in 1758.

For 135 years, arachnologists and taxonomists continued to use Clerck’s spider names. But in 1892, a congress of taxonomists decided that zoological nomenclature officially commenced with Linnaeus’s landmark Systema Naturae, which used binomial nomenclature to name thousands of species of animals for the first time. This decision rendered everything published before 1758, including Clerck’s spider descriptions, void. However, arachnologists fought to revive these lost names and in 1948, the International Commission on Zoological Nomenclature passed a motion to exempt Clerck’s 1757 publication from the 1892 decision—the only such exemption ever made in zoological nomenclature.

This gave Clerck’s names like A. angulatus priority over any scientific names that Linnaeus or any other taxonomists had used to refer to these spiders.

“A lot of scientists outside arachnology don’t know that Clerck trumps Linnaeus,” Coddington said. “This made it official that A. angulatus was the first animal ever described this way.”

When Clerck’s scientific names were restored, the spider specimens he collected regained their type status. Types are housed in museums or herbaria to preserve them in perpetuity. The National Museum of Natural History has more than 350,000 type specimens in its collection.

In 1858, a researcher stumbled across Clerck’s spider collection in a botanical garden and painstakingly pieced the specimens back together, including the A. angulatus types. But by 1965, the A. angulatus specimens were gone. Six decades passed without researchers designating a neotype. This made accurately defining A. angulatus, which comes in a variety of color patterns and is found from Europe to Korea, difficult.

Coddington and his coauthors sought to set the record straight. Matjaž Gregorič, at the Slovenian Academy of Sciences and Arts, collected several new A. angulatus specimens from Montenegro, Serbia and Slovenia. Raul Vicente, an arachnologist at the Swedish Museum of Natural History, also collected eight of the spiders from an island in the Baltic Sea off southern Sweden in the region where Clerck may have collected the original A. angulatus specimens.

The team compared the new spider specimens to Clerck’s illustrations and descriptions. They took a leg off one specimen and sequenced a particular gene in the spider’s DNA that serves as a unique serial number for that species. They compared this serial number against A. angulatus’ entire genetic code, or genome, which was published in 2025 through the Darwin Tree of Life research initiative. The genetic serial number was a match to the full genetic code, confirming that the spider specimens fit the genetic description for A. angulatus. The genetic data also suggests that some spiders in southeastern Europe and Asia identified as A. angulatus likely represent multiple distinct species that are hiding behind this scientific name.

The researchers designated one of the male spiders collected in Sweden as the neotype of A. angulatus, connecting Clerck’s scientific name to a physical specimen for the first time in at least 60 years and probably centuries. Male and female A. angulatus spiders collected from the same area as the neotype were illustrated by coauthor Taina Litwak, a scientific illustrator affiliated with the National Museum of Natural History.

The neotype will be deposited in the Swedish Museum of Natural History, where it will join Clerck’s surviving spider specimens. Six of the other spiders collected in Sweden will be deposited into the National Museum of Natural History’s national insect collection, which houses a world-renowned trove of arachnids. Coddington will place a tissue sample from one of these specimens in the museum’s Biorepository to ensure researchers can easily analyze this important spider’s DNA well into the future.

“It’s going to be stored at minus 190 degrees centigrade in perpetuity because the Smithsonian is in the forever business,” he said.

In addition to Coddington and Litwak, the study includes authors affiliated with the University of Iceland; Pro Natura; the Swedish Museum of Natural History; the Slovenian Academy of Sciences and Arts; the National Institute of Biology, Slovenia; and Hubei University.