Researchers Baffled After Finding New Species of Crayfish Hiding Amongst Common Aquarium Pets for Over Two Decades

Scientists have discovered a new species of colorful crayfish hiding in plain sight as a popular aquarium pet for over two decades, stated Popular Science. The new species, named Cherax pulverulentus—or "dusty crayfish," came upon examination in the normal delivery of Indonesian pet crayfish, which a team of scientists with the Czech University of Life Sciences Prague had ordered in March 2023.

The discovery came as a surprise to the research team led by zoologist, Jiří Patoka, who noticed several distinctively colored specimens among their purchased shipment. It wasn't until they conducted DNA analysis and an extremely detailed morphological study on six specimens that they identified it was, in fact, a new species. They have since published their findings in the journal Zootaxa.

What makes the discovery particularly interesting is that this crayfish was previously widely traded, under various names such as "Hoa Creek," "Irian Jaya," and "Blue Moon" crayfish, in the aquarium pet trade throughout Europe, Japan, the United States, and Indonesia, according to Smithsonian Magazine. It had, however, never before been scientifically described or recognized as distinct from other similar species.

The dusty crayfish comes in two striking color varieties from the Indonesian part of New Guinea. Its purple form has a turquoise body, colored with purple spots and distinct white coloration over its joints and tail. The blue variety is darker with bright orange-colored joints and tail. These bright colors, coupled with large eyes and slimly built bodies, have further driven their appeal for aquarium keepers. "Like the other members of this genus, this crayfish is aggressive, strictly freshwater, probably moderately burrowing, and omnivorous," Patoka told Popular Science. These crustaceans grow larger than four inches and commonly live for five to ten years. Their Latin name "pulverulentus" describes their dusty appearance given by the dot pattern on their exoskeleton.

The discovery has underlined an enormous knowledge gap in aquatic biodiversity. While common in pet trades, very little is known about the natural behavior of these crayfish. To date, the research team has seen only one wild-caught specimen: a blue form collected in a Hungarian thermal spring, likely released there by a former pet owner. This is an extremely timely discovery concerning biodiversity conservation in New Guinea. "Crayfish are just one group of awesome animals native to New Guinea, the island facing many environmental risks," Patoka said, according to Popular Science.

What is particularly important for its conservation prospects is the formal classification that unnamed species cannot be given the resources they need to protect and manage. It does point, though, to a more vital question of the responsible ownership of pets and the trade in aquatic pets. The researchers stress the importance of proper species identification and management in the pet trade industry, particularly given the risks of introducing non-native species into local ecosystems. "Do not release your pets outdoors!" warned Patoka, drawing attention to a possible ecological implication of aquarium dumping, stated Popular Science.