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.

Thoburnia rhothoeca
Thoburnia rhothoeca
(Torrent Sucker)
Native Transplant

Copyright Info
Thoburnia rhothoeca (Thoburn in Jordan and Evermann, 1896)

Common name: Torrent Sucker

Taxonomy: available through www.itis.govITIS logo

Identification: Page and Burr (1991); Jenkins and Burkhead (1994); Stauffer et al. (1995).

Size: 18 cm.

Native Range: Page and Burr (1991); Jenkins and Burkhead (1994); Stauffer et al. (1995).

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 Thoburnia rhothoeca are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
VA194519946Chowan; Middle Roanoke; Rapidan-Upper Rappahannock; Roanoke; South Branch Potomac; Upper James
WV197319731South Branch Potomac

Table last updated 7/19/2024

† Populations may not be currently present.

Means of Introduction: Probably due to a bait bucket release. Jenkins and Burkhead (1994) suggested the Rappahannock introduction took place in the upper Rapidian and spread from there.

Status: Established in Virginia and West Virginia.

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: While there is some question regarding this species' status in the Shenandoah system, Jenkins and Burkhead (1994) treated it as native. This species was formerly present in the upper New River drainage, Virginia, but is now apparently extirpated (Page and Burr 1991). Its presence in that drainage is somewhat confounding. Jenkins and Burkhead (1994) stated that all of the records from this drainage are suspect and, indeed, rejected one of the records. However, they concede that three of the records from that area cannot be clearly refuted and may be valid. In the end, they "grudgingly agree that T. rhothoeca is probably native to the New drainage". Stauffer et al. (1995) also treated it as native to the New drainage in West Virginia but did not discuss the matter. Conversely, the Torrent Sucker's presence in the New may have been the result of an early introduction (Gilbert, personal communication). Gilbert believes that this is an Atlantic Slope species, not an Ohio drainage species that entered the Atlantic Slope via stream capture. He believes that given the pronounced elevational differences between the plateau on which the New River is situated and the eastern slope, stream capture and faunal transfer in this region could only have occurred in a a one-way direction (west to east). The fact that this species was localized and rare in the drainage (Jenkins and Burkhead 1994) lends support to the hypothesis that it may have been introduced.

References: (click for full references)

Jenkins, R. E., and N. M. Burkhead. 1994. Freshwater fishes of Virginia. American Fisheries Society, Bethesda, MD.

Lee, D. S., C. R. Gilbert, C. H. Hocutt, R. E. Jenkins, D. E. McAllister, and J. R. Stauffer, Jr. 1980 et seq. Atlas of North American freshwater fishes. North Carolina State Museum of Natural History, Raleigh, NC.

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.

Stauffer, J. R., Jr., J. M. Boltz, and L. R. White. 1995. The fishes of West Virginia. West Virginia Department of Natural Resources. Academy of Natural Sciences of Philadelphia, Philadelphia, PA. 389 pp.

Other Resources:
FishBase Summary

Author: Fuller, P.

Revision Date: 6/27/2019

Peer Review Date: 6/5/2000

Citation Information:
Fuller, P., 2024, Thoburnia rhothoeca (Thoburn in Jordan and Evermann, 1896): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=370, Revision Date: 6/27/2019, Peer Review Date: 6/5/2000, Access Date: 7/19/2024

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.


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Citation information: U.S. Geological Survey. [2024]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [7/19/2024].

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