The discovery of a new spider species did not begin in a remote forest or during an expedition. It happened inside a museum, where two amateur spider enthusiasts were working through specimens that had remained largely unnoticed for years. Valerie Warhol, an informatics assistant, and Amy Bianco, a part-time volunteer at Carnegie Museum of Natural History, found four rusty-orange trapdoor spiders in a jar while examining the museum’s arachnid collection. Their careful investigation eventually showed that the spiders represented a species unknown to science, which was later named Cyclocosmia johndenveri after the singer named John Denver.
Amateur spider hunters’ routine work led to the discovery of John Denver species
Warhol and Bianco were not setting out to discover a new species. Their regular work involved going through specimens that had not received much attention, identifying them and helping to digitise and catalogue the museum’s holdings. According to Carnegie Magazine, this work is important because turning physical specimens and their labels into detailed digital records allows researchers around the world to access collections that might otherwise remain difficult to study.The scale of that work is enormous. Carnegie Museum of Natural History holds about 18 million invertebrate specimens, making its collection one of the largest in the United States. Yet only around 1% had been digitised when Warhol described the state of the collection. That meant there was still a huge amount waiting to be examined, including specimens that could hold information missed when they were first collected.In spring 2025, Warhol and Bianco were working through the arachnid collection when they came across a jar containing four rusty-orange trapdoor spiders. The specimens had been collected in West Virginia in 1994, but their identity did not immediately fit what was already known about these spiders.
Carnegie Museum of Natural History in Pittsburgh, Pennsylvania. Image Credit: Wikimedia Commons
The West Virginia specimens did not match any known spiders
Bianco recognised the spiders as members of Cyclocosmia, a group of trapdoor spiders sometimes known as Oreo cookie spiders because of their large, flattened abdomens marked by ridges. These ridges are thought to help protect the spiders from predators while they remain inside their underground tunnels.The location of the specimens quickly raised questions. At the time, recorded Cyclocosmia species were known from Mexico and the southern United States, while these particular spiders had come from West Virginia. That left two possibilities. One, the specimens could represent a significant extension of the known range of an existing species, or second, they could belong to a species that had never been formally recognised.Warhol and Bianco then examined the spiders more closely. Identifying the species required counting the ridges on the spiders’ flattened abdomens under magnification. The number did not correspond with any known Cyclocosmia species, providing another reason to suspect that the museum drawer contained something unusual.
The biologist who helped confirm the unusual spider
The pair sought help from Danniella Sherwood, a biologist with the Arachnology Research Association in the United Kingdom. Sherwood had recently described a new trapdoor spider from Vietnam and therefore had particular experience with the genus. Her advice directed Warhol and Bianco towards another feature that could help settle the identification.That feature was found on the pedipalps, the small appendages near a spider’s mouth. These structures have several functions, including helping spiders handle food. In mature males, however, they also become reproductive structures used to transfer sperm. Their shape can be highly specific to a species.Using highly magnified photographs supplied by Warhol and Bianco, Sherwood examined the pedipalps of the museum specimens. The photographs showed that their shape differed from those recorded for other trapdoor spiders. This provided the evidence needed to establish that the specimens represented a previously undescribed species.
Why the new species carries John Denver’s name
The spiders’ West Virginia origin led Sherwood to suggest a name connected with John Denver, the singer and songwriter who had a strong association with the state through his song Take Me Home, Country Roads. The resulting scientific name was Cyclocosmia johndenveri.The discovery was formally recognised when its description was published in the scientific journal Natura Somogyiensis. Warhol and Bianco were included as co-authors of the paper, marking an achievement for two people whose work with spiders was not based on conventional academic research careers.Their discovery also illustrates why museum collections can remain scientifically valuable long after specimens are first collected. The discovery emerged not from a fresh expedition, but from patiently revisiting material already held in the institution.
What remains unknown about the John Denver spider
Even after the species was officially described, the investigation was not complete. According to Carnegie Magazine, Warhol said that researchers still do not have a female specimen of Cyclocosmia johndenveri. That leaves important aspects of the species’ biology and appearance still to be documented.West Virginia also has relatively little spider research, according to Warhol. The researchers hope that someone might eventually photograph a living example and upload the record. Such an observation could provide another valuable piece of information about the species.
