Supplementary information.

Review of previous reports of Dreissena polymorpha colonising crayfish exoskeletons.

Proportion of colonised crayfish was calculated for total sample sizes over 10; N/A indicates unavailable data.

Crayfish species / Locality, country / Proportion and/or number of colonized crayfish / Reference
Astacus astacus / Poland / N/A / Kulmatycki, W., 1932. Omólek – bąk na raku rzecznym. Czasopismo Przyrodnicze, 6: 5-6.
Astacus leptodactylus / Balaton Lake, Hungary, / 1 ind
photo only / Sebestyén, O., 1938. Colonization of two new fauna-elements of Pontus-origin (Dreissensia polymorpha Pall. and Corophium curvispinum G. O. Sars forma devium Wundsch) in Lake Balaton. Verhandelungen der Internationalen Vereinigung für theoretische und angewandte Limnologie 8: 169-182.
A.leptodactylus / Rostov Province, Russia / >1 ind / Lamanova, A. I., 1971. Attachment by zebra mussels and acorn barnacles on crayfish. Gidrobiologicheski Zhurnal 6: 105-107.
Orconectes limosus / Maine, France / 1 ind / Laurent, P. J. & M. Suscillon, 1962. Les écrevisses en France. Annales de la Station Centrale d’Hydrobiologie Appliquée 9: 333-395.
unknown / Lake Erie, U.S.A. / ca 30 inds / Nalepa, T.F. & D.W. Schloesser (eds), 1993. Zebra Mussels: Biology, Impacts, and Control. Lewis Publishers, Boca Raton.
O. limosus / Lac Léman, France / N/A / Laurent, P. J., 1994. Zebra mussels on crayfish. IAA Newsletter 16, 4: 4-5.
O. limosus / Dąbie Lake, Poland / 1%; 6 inds
(total n: = 600) / Śmietana, P., 1996. Attachment of zebra mussel, Dreissena polymorpha (Pall.) to the exoskeleton of Orconectes limosus (Raf.) from the Dąbie Lake. Przeglad Zoologiczny 40: 69-72 [Polish, Eng. abstr].
Orconectes rusticus / Green Bay, Lake Michigan, U.S.A. / 6 inds
(n: – 25-50), 12-14% / Brazner, J. C. & D. A. Jensen, 2000. Zebra mussel (Dreissena polymorpha [Pallas]) colonisation of rusty crayfish (Orconectes rusticus [Girard]) in Green Bay, Lake Michigan. American Midland Naturalist 143(1): 250-256.
Orconectes luteus / Mississippi river, Illinois, U.S.A. / 1 ind in each of 3 samples
(n: = 2, 1 and 4)
(total n =: 290) / Wetzel, J. E., W. J. Poly & J. W. Fetzner, Jr., 2004. Morphological and genetic comparison of golden crayfish, Orconectes luteus, and rusty crayfish, Orconectes rusticus, with range corrections in Iowa and Minnesota. Journal of Crustacean Biology 24: 603–617.
Orconectes pardalotus / Ohio river, Illinois, U.S.A. / 0.5%; 1 ind
(total n : 200) / Wetzel, J. E., W. J. Poly & J. W. Fetzner, Jr., 2005. Orconectes pardalotus, a new species of crayfish (Decapoda: Cambaridae) from the lower Ohio River with notes on its life history. Aqua, Journal of Ichthyology and Aquatic Biology 10: 57–72.
O. limosus / Kopački Rit, Croatia / 1 ind
photo only / Lajtner, J., G. I. V. Klobučar, I. Maguire, A. Lucić, A. Štambuk & R. Erben, 2005. They came from the Danube River – History and present status of Dreissena polymorpha and Orconectes limosus in Croatia. INWAT: Biological invasions in inland waters. Firenze, 5-7 May 2000, pp. 42-43.