simus, Cyprinodon Humphries [J. M.] & Miller [R. R.] 1981:60, Figs. 3D, 4B, 5D [Copeia 1981 (no. 1); ref. 8587] Chichancanab Lagoon, in lagoon at southern end on northern side of highway 184, Yucatán, Mexico. Holotype: UMMZ 203905. Paratypes: TU 111577 (1); UMMZ 196545 (17), 201736 (2), 201750 (5), 201757 (1), 201762 (18, 5 c&s), 203906 (1, allotype); USNM 220014 (1). Type catalog: Bart & Taylor 1993:52 [ref. 20906]. Also appeared in Humphries & Miller 1981:136 [ref. 8588]. •Valid as Cyprinodon simus Humphries & Miller 1981 -- (Gamboa Pérez 1992:312 [ref. 38704], Espinosa Pérez et al. 1993:34 [ref. 22290], Lazara 2001:93 [ref. 25711], Strecker 2002:301 [ref. 26655], Costa in Reis et al. 2003:550 [ref. 27061], Nelson et al. 2004:109 [ref. 27807], Strecker 2005:107 [ref. 28252], Miller 2006:309 [ref. 28615], Scharpf 2007:30 [ref. 30398], Page et al. 2013:108 [ref. 32708], Lozano-Vilano & De la Maza-Benignos 2016:28 [ref. 35401], Esmaeili et al. 2018:16 [ref. 36738], Page et al. 2023:143 [ref. 40505], Aguilar-Medrano & Vega-Cendejas 2024:[3] [ref. 41240]). Current status: Valid as Cyprinodon simus Humphries & Miller 1981. Cyprinodontidae: Cyprinodontinae. Distribution: Southern North America: endorheic Laguna Chichancanab (Quintana Roo, Mexico) endemic. Habitat: freshwater.