concentricus, Urobatis Osburn [R. C.] & Nichols [J. T.] 1916:144, Fig. 2 [Bulletin of the American Museum of Natural History v. 35 (art. 16); ref. 15062] East side of Esteban Island, Gulf of California, Mexico. Holotype: USNM 87539 [ex AMNH 5199]. Paratypes: AMNH 11801-02 (1, 1). •Perhaps a synonym of Urobatis halleri (Cooper 1863) -- (Thomson et al. 2000:282 [ref. 25640]). •Valid as Urolophus concentricus (Osburn & Nichols 1916) -- (Nishida 1990:92 [ref. 19783], Allen & Robertson 1994:34 [ref. 22193], Castro-Aguirre & Espinosa Pérez 1996:48 [ref. 22793], De La Cruz Agüero et al. 1997:35 [ref. 24545], Nelson et al. 2004:56 [ref. 27807], Page et al. 2013:56 [ref. 32708]). •Valid as Urobatis concentricus Osburn & Nichols 1916 -- (McEachran in Fischer et al. 1995:789 [ref. 22829], Compagno 1999:494 [ref. 25589], Love et al. 2005:13 [ref. 37547], Del Moral-Flores et al. 2015:510 [ref. 33729], Galván-Villa et al. 2016:143 [ref. 34871], Del Moral-Flores et al. 2016:122 [ref. 34398], Weigmann 2016:160 [ref. 34211] see remarks, Last & McEachran 2016:658 [ref. 35013], Ehemann et al. 2018:27 [ref. 36194], González-Acosta et al. 2021:7 [ref. 38361], Love et al. 2021:27 [ref. 39279], Page et al. 2023:47 [ref. 40505], Vela-Espinosa et al. 2023:5 [ref. 40981]). Current status: Valid as Urobatis concentricus Osburn & Nichols 1916. Urotrygonidae. Distribution: Eastern Pacific: Pacific coast of central Baja California (Mexico) south to Oaxaca (Mexico), including Gulf of California (Mexico). Habitat: marine.