The pleurobranchid genus of sea slugs was formerly believed to consist of only two species, none of which had been observed in UK waters until recently.\
However, while doing research in the waters off the southwest coast of England, scientists from the Centre for Environmental Fisheries and Aquaculture Science (CEFAS) found a third species.
Pleurobranchaea britannica is the name given to it. CEFAS and the Instituto Espanol de Oceanografía conducted trips in the Celtic Sea and western Channel in 2018 and 2019 and discovered it.
The new species, a kind of side-gill sea slug measuring two to five centimeters, was found in fourteen specimens.
Although there are other widespread species of sea slugs, this particular variety is more commonly found in the Mediterranean Sea’s warmer waters. Scientists believe that the continuous consequences of climate change are what caused it to wander so far north.
Upon initial analysis, scientists believed they had found a new species, but subsequent research revealed it was actually a solitary species.
