Ctenogobius sagittula (Günther, 1862) .

Lancetail Goby, Longtail Goby; Gobio Aguzado.

Distribution: Global: Eastern Pacific Ocean; from San Diego Bay, California, USA, to Peru; entering estuaries and littoral lagoons and ascending river courses; Costa Rica: Ni, Te, Be, Ba, Ta, Pi, Tr and Co (Pacific), 0– 32 m.a.s.l., Per, Dia.

Occurrence and conservation status: Nat, LC.

References: Bussing (1966: 237, as Gobionellus sagittula —synonym; listed, information on distribution), Angulo et al. (2013: 1008; listed, including taxonomic information and distributional data) and Robertson &Allen (2015: 2103; detailed description, including illustrations, information on distribution, with a map, and ecology).