The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.

Iotichthys phlegethontis
Iotichthys phlegethontis
(Least Chub)
Native Transplant

Copyright Info
Iotichthys phlegethontis (Cope, 1874)

Common name: Least Chub

Taxonomy: available through www.itis.govITIS logo

Identification: Sigler and Miller (1963); Sigler and Sigler (1987; 1996); Page and Burr (1991).

Size: 6.4 cm.

Native Range: Streams near Salt Lake City and freshwater ponds and swamps around Great Salt Lake, Utah Lake, Beaver River, Parowan Creek, Clear Creek, and Provo River (Sigler and Miller 1963) in the Bonneville basin, northern Utah (Page and Burr 1991).

Native range data for this species provided in part by NatureServe NS logo
Hydrologic Unit Codes (HUCs) Explained
Interactive maps: Point Distribution Maps

Nonindigenous Occurrences:

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 Iotichthys phlegethontis are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
ND201920191Upper James

Table last updated 6/19/2024

† Populations may not be currently present.

Means of Introduction: Intentionally stocked for conservation purposes to create another population of a rare species.

Status: Status of stockings conducted in the late 1980s has not been evaluated (Sigler and Sigler 1996).

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.

Remarks: Voucher specimens: California (LACM 45699-1, The Least Chub is under review for listing as a federally endangered species (U.S. Fish and Wildlife Service 1997).45701-1).

Other Resources:
FishBase Summary

Author: Fuller, P.

Revision Date: 5/16/2000

Peer Review Date: 5/16/2000

Citation Information:
Fuller, P., 2024, Iotichthys phlegethontis (Cope, 1874): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=552, Revision Date: 5/16/2000, Peer Review Date: 5/16/2000, Access Date: 6/19/2024

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.


The data represented on this site vary in accuracy, scale, completeness, extent of coverage and origin. It is the user's responsibility to use these data consistent with their intended purpose and within stated limitations. We highly recommend reviewing metadata files prior to interpreting these data.

Citation information: U.S. Geological Survey. [2024]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [6/19/2024].

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