🌍 Hidden in Plain Sight: Two Native Crayfish Species Mistaken for Invasive Signal Crayfish
In a groundbreaking discovery, scientists from the University of Illinois Urbana-Champaign have identified two previously unknown crayfish species in the Pacific Northwest—Okanagan crayfish and misfortunate crayfish. Long mistaken for the invasive signal crayfish, these native species were hiding in plain sight for decades.
This major finding, published in the peer-reviewed journal Zootaxa, sheds new light on freshwater biodiversity and the urgent need for crayfish conservation.
🔬 How Were These Crayfish Species Identified?
The discovery was the result of years of scientific observation, genetic sequencing, and morphological analysis. Using advanced genome skimming techniques to analyze mitochondrial and nuclear DNA, researchers were able to distinguish the new species from the signal crayfish (Pacifastacus leniusculus).
“We underestimated the diversity of crayfish in their native range,” said Dr. Eric Larson, Associate Professor at the University of Illinois. “What we thought was one species turned out to be three.”
Dr. Larson and his research team conducted extensive field sampling, confirming that these newly named crayfish are genetically and physically distinct.
🚨 At Risk: Invasive Crayfish Threaten Native Biodiversity
While the discovery is exciting, it comes with a warning: both the Okanagan crayfish and the misfortunate crayfish are already threatened by invasive species like the rusty crayfish and virile crayfish.
These aggressive invaders outcompete native species for resources, displace populations, and disrupt freshwater ecosystems.
“One of the biggest threats to native crayfish is human activity,” Larson emphasized. “People often move crayfish between water bodies, either as fishing bait, for aquaculture, or even from classroom tanks. These actions can introduce invasive species that are nearly impossible to remove.”
🧬 Why the Name “Misfortunate Crayfish”?
The name misfortunate crayfish has a tragic backstory. By the time scientists officially identified the species, it had already lost a significant portion of its natural habitat to invasive crayfish.
“The name reflects the species’ bad luck—it went unrecognized until much of its home was already destroyed,” Larson explained.
🌱 A Call for Crayfish Conservation and Awareness
The researchers hope that naming and describing these species will lead to conservation efforts. In the world of biodiversity, recognition is often the first step toward protection.
“Our work aims to highlight the importance of native species and the dangers they face from biological invasions,” Larson said. “Now that these crayfish have names, they also have a better chance at survival.”
🧠 Did You Know?
- There are over 600 known species of crayfish worldwide.
- The signal crayfish is considered one of the most invasive freshwater species globally.
- Crayfish play a vital ecological role in freshwater habitats as both prey and predators.
📚 Research Citation
Larson, E.R. et al. (2025). Genome skimming supports two new crayfish species from the genus Pacifastacus Bott, 1950 (Decapoda: Astacidae). Zootaxa, DOI: 10.11646/zootaxa.5632.3.4