Original description as Agosia chrysogaster:
- Girard, Charles Frederic. 1856. "Researches upon the cyprinoid fishes inhabiting the fresh waters of the United States, west of the Mississippi Valley, from specimens in the museum of the Smithsonian Institution". Proceedings of the Academy of Natural Sciences of Philadelphia. 8:165-213 (ffm04542)
- Agosia metallica Girard, 1856, with type locality at Rio San Pedro, an affluent of Gila River, Arizona, U.S.A. Determiner: Gilbert, 1998
- Hyborhynchus siderius Cope, 1875, with type locality at Camp Lowell, on lower part of Cienega Creek, Pima County, Arizona, U.S.A. Determiner: Gilbert, 1998
Conservation: Agosia chrysogaster is evaluated by the international union for the conservation of nature in the iucn red list of threatened species as (LC) least concern (2018). Threats include habitat alterations and interactions with non-native fish species. Large areas of habitat have been destroyed by dewatering, stream diversion, groundwater pumping, dam construction, channel and watershed erosion, and other factors. Localized or regional threats have likely resulted in population decline or extirpation at the local scale. however, the total population is very large and the species is represented by a large number of locations and occurrences (NatureServe et al., 2019).