Alfaro cultratus (Regan, 1908) .

Knife Livebearer; Olomina, Olomina de Estero, Alumina, Killi, Olomina de (Anastasio) Alfaro.

Distribution: Global: Middle America; from eastern Honduras to western Panama, Atlantic and Pacific drainages; Costa Rica: LN, RF, SJ, SC, Sa, To, Pa, Ma, Si (Atlantic), Te and Ta (Pacific), 0–1060 m.a.s.l., Sec, Pot.

Occurrence and conservation status: Nat, LC.

References: Bussing (1966: 236; listed, information on distribution), Bussing (1987: 129; 1998: 192; brief description, including illustrations and an identification key, information on distribution, with a map, and ecology) and Angulo et al. (2013: 996; listed, including taxonomic information and distributional data).