Common name: an oligochaete
Synonyms and Other Names: Ripistes parasitica, Ripistes macrochaeta
available through www.itis.gov
Identification: Dorsal setal bundles on segments VI–VIII are characterized by 2–16 giant hair setae; following segments have 1–3 moderately long hairs. Ventral setae are absent on segments IV and V. Stomachal dilation is sudden, beginning in segments VI or VII. Clitellum is located in ½ V–½ VIII; spermathecal ampulla are large and baglike with a fairly long, well-defined duct. Penial setae 2 per bundle with a simple hook. Swims with sagittal movements; constructs fixed, hyaline tubes (Brinkhurst 1971, Brinkhurst and Jamieson 1971).
Note: segments are counted from anterior to posterior using roman numerals.
Size: 8 mm
Native Range: Ripistes parasita is native to Europe and Lake Baikal in Asia (Brinkhurst and Jamieson 1971).
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 Ripistes parasita are found here.
Table last updated 12/8/2023
† Populations may not be currently present.
Ecology: This aquatic oligochaete has been found in waters between 6 m and 10 m deep in the Great Lakes, both on bare, rocky substrates and amongst macrophyte vegetation (Barton and Griffiths 1984; Winnell and Jude 1987; Grigorovich et al. 2003). Specimens taken from riverine habitats occupied waters between 0.9 m and 3.5 m deep and in flow rates ranging from 0 to 50 cm/s (Simpson and Abele 1984; Montz 1988).
Means of Introduction: The prevalence of R. parasita at sites near major shipping ports suggests invasion via international shipping (Winnel and Jude 1987).
Status: Established where collected. Additionally, Montz (1988) stated that the sporadic distribution of R. parasita could be the result of typical benthic sampling methods leading to either the loss or distruction of this organism, and that this naidid may be much more widespread than records show.
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)
Barton, D.R., and M. Griffiths. 1984. Benthic invertebrates of the nearshore zone of eastern Lake Huron, Georgian Bar, and North Channel. Journal of Great Lakes Research 10(4): 407-416.
Brinkhurst, R.O. 1971. A Guide to the Identification of British Aquatic Oligochaeta. Freshwater Biological Association. Scientific Publication No. 22, 2nd edition.
Brinkhurst, R.O., and B.G.M. Jamieson. 1971. Aquatic Oligochaeta of the World. University of Toronto Press. Toronto and Buffalo.
Grigorovich, IA. A.V. Korniushinm D.K. Gray, I.C. Duggan, R.I. Coulatti & H.J. MacIsaac. 2003. Lake Superior: an invasion coldspot? Hydrobiologia 499: 191-210
Mills, E.L., J.H. Leach, J.T. Carlton, and C.L. Secor. 1993. Exotic species in the Great Lakes: a history of biotic crisis and anthropogenic introductions. Journal of Great Lakes Research 19(1): 1-54.
Montz, G.R. 1988. The occurrence of Ripistes parasita (Oligochaeta:Naididae) in Minnesota and its implications for benthic sampling. Journal of the American Benthological Society 7(2): 160-162.
Nalepa, T.F., D.J. Hartson, D.L. Fanslow, G.A. Lang, S.J. Lozano. 1998. Declines in Benthic Macroinvertebrate Populations in Southern Lake Michigan, 1980-1993. Canadian Journal of Fisheries and Aquatic Sciences 55(11): 2402-13.
Simpson, K.W., and L.E. Abele. 1984. Ripistes parasita (Schmidt) (Oligochaeta: Naididae), a distinctive oligochaete new to North America. Freshwater Invertebrate Biology 3(1): 36-41.
Spencer, D.R., and P.L. Hudson. 2003. The Oligochaeta (Annelida, Clitellata) of the St. Lawrence Great Lakes Region: An Update. Journal of Great Lakes Research 29(1): 89-104
Stewart, T.W., and J.M. Haynes. 1994. Benthic Macroinvertebrate Communities of Southwestern Lake Ontario Following Invasion of Dreissena. Journal of Great Lakes Research 20(2): 479-493.
Wahab, M. A., Stirling, H. P. and Robertson, D. A. 1989. Influence of brown trout, Salmo trutta L., predation on the benthic fauna of earthen ponds. Aquaculture Research 20:147–158.
Winnell, M.H., and D.J. Jude. 1987. Benthic community structure and composition among rocky habitats in the Great Lakes and Keuka Lake, New York. Journal of Great Lakes Research 13(1):3-17.
Jacobs, G., J. Larson, A. Fusaro, and T. Makled
Revision Date: 9/12/2019
Jacobs, G., J. Larson, A. Fusaro, and T. Makled, 2023, Ripistes parasita: U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=2244, Revision Date: 9/12/2019, Access Date: 12/9/2023
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.