A new type of shrimp has been seen in Maltese waters.

The penaeid shrimp (Penaeus aztecus) is originally from American and Mexican waters but has now spread to eastern and central regions of the Mediterranean Sea. It is believed to have spread to the Mediterranean after being carried in ballast water released by large ships crossing to the Mediterranean from the Americas.

News of the alien species sighting was released by Aquatic Resources Malta, a government-run organisation dedicated to aquaculture and fisheries research.

The penaeid shrimp looks similar to the local Caramote prawn (Penaeus kerathurus), but lacks the red striping observed in this native species, Aquatic Resources Malta noted.

The organisation’s Marine Biology and Research team first noted the new species during a routine sampling of trammel nets in late 2024. The team has now submitted a scientific paper about the finding, with the paper confirmed for publication.

“We ask the public to not shy away and contact us when encountering unfamiliar sea life, it is our pleasure to answer your curiosities and share in your discoveries,” Aquatic Resources Malta said.

Alien species are species that are introduced to new geographical areas through human activity.

Many such species have been recorded in Maltese waters in recent years. Among the more exotic are the fugu pufferfish, a form of rabbitfish known as the dusky spinefoot which is known among fishermen as an qawsalla,  the oriental mussel and the Red Sea mantis shrimp.

A citizen science campaign - Spot the Alien - allows people to report sightings of alien animals and fish online.