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.

Austrolebias bellottii
Austrolebias bellottii
(Argentine pearlfish)

Copyright Info
Austrolebias bellottii (Steindachner, 1881)

Common name: Argentine pearlfish

Synonyms and Other Names: Cynolebias bellottii, Cynolebias belloti, (pavito).

Taxonomy: available through www.itis.govITIS logo

Identification: Costa (1990) provided diagnostic characters and included this species in his identification keys to the genera and species of the subfamily Cynolebiatinae. A few distinguishing characteristics were also provided by Boschi (1957) and Sterba (1973). Moyle (1976) included this species in his keys for California fishes. Color photographs appeared in Mills and Vevers (1989), Axelrod et al. (1985), and Costa (1990). The spelling of this species is sometimes given as Austrolebias bellotti.

Size: 6.5 cm.

Native Range: Tropical America. Lower Parana basin, around Rio de la Plata, in Argentina and Uruguay, South America (W. Costa, personal communication).

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 Austrolebias bellottii are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
CA196419643Butte Creek; California Region; Santa Ana

Table last updated 3/3/2024

† Populations may not be currently present.

Ecology: Similar to many tropical killifish species, Austrolebias bellottii is an annual fish able to maintain permanent populations in temporary habitats by combining rapid growth and development with diapausing eggs that survive the dry season buried in the mud. Feeds on worms and crustaceans (Mills and Vevers 1989).

Means of Introduction: Intentionally stocked to assess its ability as a mosquito control agent, especially in ricefields (Moyle 1976; Dill and Cordone 1997). These introductions were with the approval of the Fish and Game Commission (Dill and Cordone 1997).

Status: Reported from California where all open water introductions apparently failed (Moyle 2002). Contrary to Courtenay et al. (1986, 1991), Dill and Cordone (1997) concluded that there is no evidence of past survival and establishment of this species in California open waters. However, it was temporarily established in experimental ponds at the University of California (Bay 1966; Moyle 1976; Dill and Cordone 1997); that population reportedly survived for five or six years despite repeated floodings and dryings before dying out (Legner and Medved 1972; Shapovalov et al. 1981).

Impact of Introduction: Unknown. Moyle (1976) expressed concern about the possible impact introduced annual fishes might have on the invertebrate fauna inhabiting California temporary pools.

Remarks: Bay (1966) demonstrated that Austrolebias bellottii could survive seasonal conditions typical of southern California, although egg survival was low. Austrolebias bellottii was reported as an introduction into Hawaii but apparently never was stocked in open water (Maciolek 1984). The literature is fragmentary and somewhat contradictory concerning the introduction, and possible establishment, of this species in open waters of California. Courtenay and Hensley (1979), citing Moyle (1976), stated that the species probably was established in Riverside and possibly in Los Angeles counties. Although unclear, the Los Angeles County report by Moyle (1976) may represent an open water record, whereas his Riverside record (Moyle 1976a), apparently refers to completely confined populations restricted to experimental ponds at the University of California, Riverside, Riverside County. The literature does not provide information on the outflow, if any, of the experimental ponds nor of the ricefield areas. Courtenay et al. (1986, 1991) listed this species as an exotic formerly established in California but now extirpated. Hubbs et al. (1979) cited it as not known to occur in California. Swift et al. (1993) did not mention A. bellottii in their work on freshwater fishes of southern California. Dill and Cordone (1997) provided details of the history of this species in California. They verified that a small number of adult Argentine pearlfish were stocked in study plots at the Riverside campus in Riverside County, at the Biggs Rice Experiment Station in Butte County, and at two duck clubs in Kern County. Although possibly introduced to sites in Orange and Los Angeles counties, Dill and Cordone (1997) could not find any information on such releases.

There are no known voucher specimens.

References: (click for full references)

Axelrod, H.R., W.E. Burgess, N. Pronek, and J.G. Walls. 1985. Dr. Axelrod's atlas of freshwater aquarium fishes. Tropical Fish Hobbyist Publications, Inc., Neptune City, NJ.

Bay, E.C. 1966. Adaptation studies with the Argentine pearl fish, Cynolebias bellottii, for its introduction into California. Copeia 1966:839-846.

Boschi, E. 1957. Argentine pearl fish Cynolebias bellottii Steindachner 1881. English translation of Spanish by W. Voderwinkler. Tropical Fish Hobbyist Publications, Inc., Neptune City, NJ.

Costa, W.J.E.M. 1990. Classificação e distribuição da família Rivulidae (Cyprinodontiformes, Aplocheiloidei). Revista Brasileira de Biolgia 50(1):83-89.

Courtenay, W.R., Jr., and D.A. Hensley. 1979. Survey of introduced non-native fishes. Phase I Report. Introduced exotic fishes in North America: status 1979. Report Submitted to National Fishery Research Laboratory, U.S. Fish and Wildlife Service, Gainesville, FL.

Courtenay, W.R., Jr., D.A. Hensley, J.N. Taylor, and J.A. McCann. 1986. Distribution of exotici fishes in North America. 675-698 in Hocutt, C.H., and E.O. Wiley, eds. The zoogeography of North American freshwater fishes. John Wiley and Sons. New York, NY.

Courtenay, W. R., Jr., D. P. Jennings, and J. D. Williams. 1991. Appendix 2: exotic fishes. Pages 97-107 in Robins, C. R., R. M. Bailey, C. E. Bond, J. R. Brooker, E. A. Lachner, R. N. Lea, and W. B. Scott. Common and scientific names of fishes from the United States and Canada, 5th edition. American Fisheries Society Special Publication 20. American Fisheries Society, Bethesda, MD.

Dill, W.A., and A.J. Cordone. 1997. History and status of introduced fishes in California, 1871-1996. California Department of Fish and Game Fish Bulletin, volume 178.

Hubbs, C.L., W.I. Follett, and L.J. Dempster. 1979. List of the fishes of California. Occassional Papers of the California Academy of Science 133:1-51.

Legner, E.F., and R.A. Medved. 1972. Predators investigated for the biological control of mosquitoes and midges at the University of California, Riverside. Proceedings of the California Mosquito Control Association 40:109-111.

Maciolek, J.A. 1984. Exotic fishes in Hawaii and other islands of Oceania. 131-161 in W. R. Courtenay, Jr., and J. R. Stauffer, Jr., eds. Distribution, biology, and management of exotic fishes. The Johns Hopkins University Press, Baltimore, MD.

Mills, D., and G. Vevers. 1989. The Tetra encyclopedia of freshwater tropical aquarium fishes. Tetra Press, Morris Plains, NJ.

Moyle, P.B. 1976. Inland fishes of California. University of California Press, Berkeley, CA.

Moyle, P.B. 2002. Inland fishes of California. Univeristy of California Press, Berkeley, CA.

Parenti, L.R. 1981. A phylogenetic and biogeographic analysis of cyprinodontiform fishes (Teleostei, Atherinomorpha). Bulletin of the American Museum of Natural History 168(4):335-557.

Shapovalov, L., A.J. Cordone, and W.A. Dill. 1981. A list of freshwater and anadromous fishes of California. California Fish ad Game 67(1):4-38.

Sterba, G. 1973. Freshwater fishes of the world. English translation and revision from German. Two volumes. Tropical Fish Hobbyist Publications, Inc., Neptune City, NJ.

Swift, C.C., T.R. Haglund, M. Ruiz, and R.N. Fisher. 1993. The status and distribution of the freshwater fishes of southern California. Bulletin of the Southern California Academy of Science 92(3):101-167.

Other Resources:
FishBase Summary

Author: Leo Nico, and Matt Neilson

Revision Date: 5/7/2019

Peer Review Date: 6/28/2011

Citation Information:
Leo Nico, and Matt Neilson, 2024, Austrolebias bellottii (Steindachner, 1881): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=879, Revision Date: 5/7/2019, Peer Review Date: 6/28/2011, Access Date: 3/4/2024

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 [3/4/2024].

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