Eleotris perniger (Cope, 1871) .

Smallscaled Spinycheek Sleeper; Guavina, Pez Perro, Dormilón, Guavina Espinosa.

Distribution: Global: Western Atlantic Ocean; from Bermuda, Bahamas, South Carolina and northern Gulf of Mexico, USA, to southeastern Brazil; entering estuaries and littoral lagoons and ascending river courses; Costa Rica: To, Pa, Ma and Si (Atlantic), 0– 60 m.a.s.l., Per, Dia.

Occurrence and conservation status: Nat, LC.

References: Bussing (1966: 237, as Eleotris pisonis (Gmelin 1789) —missidentification; listed, information on distribution), Bussing (1987: 246; 1998: 417, as E. pisonis —missidentification; brief description, including illustrations and an identification key, information on distribution, with a map, and ecology), Angulo et al. (2013: 1006, as E. pisonis — missidentification; listed, including taxonomic information and distributional data) and Robertson & Van Tassell (2019: 4097; detailed description, including illustrations, information on distribution, with a map, and ecology).