Abstract

Euphausiids have been well studied in several regions of the Pacific Ocean; however, there is less
information regarding euphausiids in Costa Rican waters. We analyzed euphausiid specimens collected around
Isla del Coco National Park during 2011 and 2012. A total of 130 specimens were analyzed and 13 euphausiid
species were identified, belonging to four genera and one family. An annotated list of species is presented,
with photographs and details for their identification. All species found represent new records for waters around
Isla del Coco in the Costa Rican Pacific. The most frequent species were Euphausia diomedeae, Euphausia
distinguenda, Nematoscelis gracilis and Stylocheiron affine. Rev. Biol. Trop. 64 (Suppl. 1): S221-S230. Epub
2016 Febrary 01.
Keywords: krill, holozooplankton, species composition, epipelagic zone, Costa Rica