First record of non-indigenous Paracaprella pusilla Mayer, 1890 (Crustacea: Amphipoda) in the Northern Tropical East Pacific

Despite the large number of biological invasion studies, little is known about non-indigenous caprellids in the eastern Pacific. This study represents the first record of Paracaprella pusilla Mayer, 1890, an invasive species, in the northern tropical east Pacific (NTEP) region. Caprellids were collected from June 2013 to March 2014 on fouling substrates (mainly macroalgae, sponge, and bryozoans) associated with artificial structures at four sites from the Mexican Pacific. Marinas, sheltered waters, and aquaculture farms appeared to function as caprellid nurseries and may act as distribution points to other localities. P. pusilla inhabited a wide range of artificial structures, which appears to increase their survival success and may facilitate their dispersal to new locations in the eastern Pacific Ocean.