Common name: Little Colorado sucker
available through www.itis.gov
Identification: The Little Colorado Sucker (Catastomus sp.) is a taxonomically undescribed species that is similar to the Flannelmouth Sucker (C. latipinnis). Compared to the Flannelmouth, the Little Colorado Sucker has a thicker, deeper caudal peduncle and a smaller lower lip. It usually has 11-12 dorsal rays; 73-97 (usually less than 90) lateral scales, and a slightly falcate to straight-edged dorsal fin. The Little Colorado Sucker is sharply bicolored with a dark gray to blue-black dorsal surface and a white-yellow belly coloration (Page and Burr 2011).
Further details for identification can be found in Minckley (1973) and Page and Burr (1991).
Size: 50 cm.
Native Range: Upper Little Colorado River system, Arizona (Page and Burr 2011).
Hydrologic Unit Codes (HUCs) Explained
Puerto Rico &
Interactive maps: Point Distribution Maps
Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Catostomus sp. are found here.
Table last updated 10/2/2023
† Populations may not be currently present.
Ecology: The Little Colorado Sucker inhabits the rocky pools and riffles of creeks as well as small to medium rivers and impoundments (Page and Burr 2011).
Means of Introduction: Unknown.
Status: The Little Colorado Sucker is common in the Salt River, AZ (Page and Burr 2011).
Impact of Introduction: The impacts of this species are currently unknown, as no studies have been done to determine how it has affected ecosystems in the invaded range. The absence of data does not equate to lack of effects. It does, however, mean that research is required to evaluate effects before conclusions can be made.
References: (click for full references)
Minckley, W. L. 1973. Fishes of Arizona. Arizona Fish and Game Department. Sims Printing Company, Inc., Phoenix, AZ.
Page, L.M., and B.M. Burr. 1991. A field guide to freshwater fishes of North America north of Mexico. The Peterson Field Guide Series, volume 42. Houghton Mifflin Company, Boston, MA.
Page, L.M., and B.M. Burr. 2011. Peterson field guide to freshwater fishes of North America north of Mexico. 2nd edition. Houghton Mifflin Harcourt, Boston, MA.
Revision Date: 5/9/2019
Peer Review Date: 5/16/2000
Procopio, J., 2023, Catostomus sp. Lesueur, 1817: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=356, Revision Date: 5/9/2019, Peer Review Date: 5/16/2000, Access Date: 10/2/2023
This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.