The American crab (Procambarus clarkii), an invasive species that has colonized our rivers since the 1970s, did not travel alone. A team of researchers from the University of Valencia has identified a small crustacean that was probably moving on board the crab: an invader of the invader itself. Scientists are now concentrating on finding out if this tiny animal is beneficial or harmful to the American crab, and if there isrisk of transmission to other local species.
This ‘passenger’ is calledSinuous Ankylocythereand it measures less than half a millimeter in length. You cannot live without the crab, aslays its eggs and develops by clinging to it. Researchers have identified it in more than 70 percent of a sample of American crabs collected from various locations on the Iberian Peninsula. “Sinuous Ankylocythereit is abundant and common wherever there are American crabs in Europe, “Francesc Mesquita Joanes, one of the authors of the study, explained to SINC. In addition, based on comparisons with crabs from the United States, the researchers say that this species arrived as ‘stowaway’ of the American crab when it was introduced in the peninsula, although it has taken more than 30 years to be discovered.
The challenge now is to discover if this tiny crustacean could pass to other native crabs and to know its potential consequences on the animals in which it is housed. For the research group, the effect on the host crab would be beneficial if they “cleaned” it of organic matter in contaminated places or parasites, and harmful if they fed on some parts of the crab or on the eggs of females.
The American crab was introduced in Spain in 1974 to satisfy the demand for human consumption. However, the animal has caused serious imbalances in the ecosystems and has also affected rice crops since its digging habits damage the water containment barriers in them.
