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.

Phenacogrammus interruptus
Phenacogrammus interruptus
(Congo tetra)

Copyright Info
Phenacogrammus interruptus (Boulenger, 1899)

Common name: Congo tetra

Taxonomy: available through www.itis.govITIS logo

Size: 8.0 cm male; 6.0 cm female (FishBase 2011).

Native Range: This species is native to the Middle Congo Basin in Africa (Froese and Pauly, 2012).

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 Phenacogrammus interruptus are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
PR200620061Eastern Puerto Rico

Table last updated 7/20/2024

† Populations may not be currently present.

Ecology: The Congo Tetra is benthopelagic and is found in waters with a pH between 6.0 and 8.0 (Froese and Pauly, 2012).

The Congo Tetra feeds on worms, small insects, crustaceans, and plant matter. The female lays up to 300 eggs, which sink to the bottom and hatch in 6 days. The nest is not guarded (Mills and Vevers, 1989).

Males are larger and more colorful than females (SeriouslyFish, 2012a).

Means of Introduction: Aquarium release.

Status: Established in Puerto Rico.

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)

Erdman, D.S. 1984. Exotic fishes in Puerto Rico. Pages 162-176 in W. R. Courtenay, Jr. and J. R. Stauffer, Jr. (eds.), Distribution, Biology, and Management of Exotic Fishes. Johns Hopkins University Press, Baltmore, Maryland. 430 pp.

Froese, R. and D. Pauly (eds). 2012. FishBase. World Wide Web electronic publication. Available from: http://www.fishbase.org.  Version (08/2012).

Mills, D. and G. Vevers. 1989. The Tetra encyclopedia of freshwater tropical aquarium fishes. Tetra Press, New Jersey. 208 p.

SeriouslyFish. 2012a. Phenacogrammus interruptus Congo Tetra. Available from: http://www.seriouslyfish.com/species/phenacogrammus-interruptus/ Accessed 3/26/2013.

Other Resources:
FishBase Summary

Author: Fuller, P.

Revision Date: 8/6/2013

Peer Review Date: 8/6/2013

Citation Information:
Fuller, P., 2024, Phenacogrammus interruptus (Boulenger, 1899): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=2632, Revision Date: 8/6/2013, Peer Review Date: 8/6/2013, Access Date: 7/20/2024

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 [7/20/2024].

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