A study published in the journal Zootaxa by the University of Seville (Spain) and the Museum of Natural History in Canada describes a new species of marine crustacean found on the coast of California (USA).

As José Manuel Guerra García, the main author of the study, explains: "This new species presents differences relative to other examples of the same genus in the dorsal protuberances on its body, as well as in its legs, pincers and abdomen."

The researchers have named this new crustacean Liropus minusculus on account of its small size. The males measure only around 3.3 mm and the females 2..1 mm. The appearance of this animal for the first time in the northeast Pacific enables us to find out about the biogeographical patterns of the genus and understand its speciation processes.

"Specimens of the Liropus genus can be found in both the Atlantic and the Mediterranean. Taxonomic research on caprellid crustaceans are crucial to identifying them correctly and knowing which species we are working with in ecological research and other applied studies on marine bioindicators, uses in aquaculture, extraction of compounds of pharmacological interest, etc.," stresses Guerra García.

It is estimated that we know only between 5% and 10% of the species that inhabit our planet, therefore taxonomy is crucial for characterising global biodiversity. Over the last ten years, Dr. Guerra has described eight genera and 62 new species for the science of caprellid crustaceans. This is merely one example of everything that is yet to be discovered.

Another tropical caprellid crustacean appears in the Mediterranean

The scientist also contributed to an article published recently in the journal 'Helgoland Marine Research' which discovered the presence of a species of crustacean native to Brazil, brought to Spanish coasts quite possibly by boats. "This is the caprellid crustacean Paracaprella pusilla," remarks Macarena Ros Clemente, who is the main author of the study and is responsible for the finding.

"Two species of caprellids have been brought to our coasts: Caprella scaura and Paracaprella pusilla. Only the former can be considered an invader, as P. pusilla is, for the moment, merely brought to the coast," the researchers note.

For a species to be considered an invader, it must have been proven that it has consequences, either economic or on the ecosystem, after being introduced.

"Its arrival in the Mediterranean is linked to that of marine hydrozoa, which stick to the shards of boats. Living on these hydrozoa brings them many advantages for finding refuge and capturing their prey, because the Paracaprella pusilla is fundamentally predatory and feeds on copepods -- very small crustaceans -- which become trapped in the hydrozoa," the scientists highlight.