1.  Table 5. The matrix of similarities between main North-Atlantic regions (%, resemblance measure – simple matching).

Iceland / Norway / Svalbard / Greenland / Faroes
Norway / 38.0
Svalbard / 64.2 / 22.3
Greenland / 76.0 / 33.0 / 77.1
Faroes / 75.4 / 34.6 / 70.9 / 80.4
Shetland / 72.1 / 38.0 / 68.7 / 76.0 / 81.0

2.  Fig.6. Alona werestschagini, Iceland, adult male: photo, postabdomen. Scale 0.1 mm

3.  Additional references on the freshwater Crustacea (Cladocera, Copepoda):

·  Iceland:

Adalsteinsson H (1979a) Seasonal variation and habitat distribution of benthic Crustacea in Lake Myvatn in 1973. Oikos 32:195-201

Adalsteinsson H (1979b) Zooplankton and its relation to available food in Lake Myvatn. Oikos 32:162-194

Ólafsson E, Ingólfsson A, Steinarsdóttir MB (2001) Harpacticoid copepod communities of floating seaweed: Controlling factors and implications for dispersal. Hydrobiol 453/454:189-200. doi: 10.1023/A:1013196724039

Örnólfsdóttir EB, Einarsson A (2004) Spatial and temporal variation of benthic Cladocera (Crustacea) studied with activity traps in Lake Myvat, Iceland. Aquat Ecol 38:239-251. doi: 10.1023/B:AECO.0000032059.99310.d3

Steinarsdótti MB, Ingólfsson A(2004)Itunella muelleri(Harpacticoida: Canthocamptidae): a marine species with preferences for the upper part of the littoral fringe.J Crust Biol24:440-446. doi: 10.1651/C-2468

Steinarsdóttir MB, Ingólfsson A, Ólafsson E(2003)Seasonality of harpacticoids (Crustacea: Copepoda) in a tide pool in subarctic south-western Iceland. Hydrobiol 503:211-221. doi: 10.1023/B:HYDR.0000008489.41581.d7

the Faroes:

Christoffersen K (2002) Previous studies of freshwater biota in Faroese lakes. Ann Soc Scient Faroensis Suppl 36:7-13

Enckell H (1969) Distribution and dispersal of Parastenocaridae (copepoda) in northern Europe. Oikos 20:493-507

Jensen F (1987) Notes on the benthic stream fauna of the Faroe Islands. Nat Jutlandica 22:73-80

Lauridsen TL, Hansson L-A (2002) The zooplankton community of five Faroese lakes. Ann Soc Scient Færoensis Suppl 36:70-78

Malmquist HJ, Ingimarsson F, Jóhannsdóttir EE, Ólafsson JS, Gíslason GM (2002) Zoobenthos in the Littoral and Profundal Zones of Four Faroese Lakes. Ann Soc Sci Færoensis Suppl 36:79-93

·  Shetland:

George DG, Maitland PS (1984) The fresh waters of Shetland: physical and morphometric characteristics of lochs. Freshw Biol 14:95-107. doi: 10.1111/j.1365-2427.1984.tb00025.x

Scott T, Duthie R. The inland waters of the Shetland islands. Ann Rep Fish Board Scotland 1894, 1895, 1896, 1897

Shetland Biodiversity Audit (1999) Patrick Steer (ed) Shetland Amenity Trust, London.

·  Svalbard:

Amren H (1964a) Ecological and taxonomical studies on zooplankton from Spitsbergen. Zool Bidr Uppsala 36:209-276

Amren H (1964b) Ecological studies on zooplankton populations in some ponds on Spitsbergen. Zool Bidr Uppsala 36:161-191

Coulson S (ed) (2012) The terrestrial and freshwater invertebrate fauna of Svalbard: an inventory and bibliography. Norsk Polarinstitutt Skrifter, Tromsø.

Halvorsen G, Gullestad N (1976) Freshwater Crustacea in some areas of Svalbard. Arch Hydrobiol 78:383–395

Husmann S, Jacobi HU, Meijering MPD, Reise B (1978) Distribution and ecology of Svalbard's Cladocera. Verh Internation Verein Limnol 20:2452-2456

Janiec K (1996) The comparison of freshwater invertebrates of Spitsbergen (Arctic) and King George Island (Antarctic). Pol Polar Res 17:175-204

Jørgensen I, Eie JA (1993) The distribution of zooplankton, zoobenthos and fish in lakes and ponds of the Mosself peninsula, Svalbard. NINA Forskrapp 45:1-25 NINA. NINA, Trondheim

Kotwicki L (2002) Benthic Harpacticoida (Crustacea, Copepoda) from the Svalbard archipelago. Pol Polar Res 23:185-191

Kubicek H, Terek J (1991) Zooplankton of Svalbard (Spitsbergen). Biologia 46:873-879

Meijering MPD (1979) Life cycle, ecology and timing of Macrothrix hirsuticornis Norman et Brady (Cladocera, Crustacea) in Svalbard. Polarforschung 49:157-171

Mielke W (1974) Eulitorale Harpacticoidea (Copepoda) von Spitsbergen. Mikrofauna Meeresbodens 37:161-210

Oloffson O (1918) Studien űber den sűsswasser Fauna Spitzbergens.Beitr z SystematikBiol u Tiergeogr der Crustaceen u Rotatorien. Zool Bird Uppsala 6:183-648

Richard J (1897) Entomostracés recueillis par M Ch Rabot à Jan Mayenet au Spitzberg. B Soc Zool Fr 22:193-198

Samchyshyna L, Hansson L-A, Christoffersen K (2008) Patterns in the distribution of Arctic freshwater zooplankton related to glacial history. Polar Biol 31:1427-1735. doi: 10.1007/s00300-008-0482-4

Scourfield DJ (1897) Contributions to the non-marine fauna of Spitsbergen. Part I Preliminary notes and reports on the Rhipozoda Tardigrada Entomostraca. C Proc Zool Soc Lond 784-792

Summerhayes VS, Elton CS (1923) Contributions to the ecology of Spitsbergen and Bear Island. J Ecol 11:214-286

Szymelfenig M, Kwagniewski S, W¢stawski JM (1995) Intertidal zone of Svalbard.Meiobenthos density and occurrence. Polar Biol 15:137-141

Thomasson K (1959) Zur Plankton kunde Spitzbergens. Hydrobiologia 12:226-236

Walkusz W, Storemark K, Skau T, Gannefors C, Lundberg M (2003) Zooplankton community structure; a comparison of fjords, open water and ice stations in the Svalbard area. Pol Polar Res 24:149-165

Wojtasik B,Kur J(2007)Size differences between individuals of Nannopus palustrisBrady, 1880 (Crustacea, Harpacticoida, Huntemannidae) from tidal flats on Spitsbergen. Oceanol Hydrobiol St36(4):97-108

·  Greenland:

Bennike O (2000) Palaeoecological studies of Holocene lake sediments from west Greenland. J Palaeogeogr Palaeoclimatol 155:285-304. doi: 10.1016/S0031-0182(99)00121-2

Bennike O, Björck S, Böcher J, Walker IR (2000) The Quaternary arthropod fauna of Greenland: a review with new data. Bulletin of the Geological Society of Denmark 47:111-134

Böcher J (2002) Insekter og andres mådyr. I Grønlands tjeldogferskvand Forlaget Atuagkat, Nuuk

Frey DG (1991) First fossil records of Daphnia headshields and shells (Anomopoda, Daphnidae) about 10 000 years old from northernmost Greenland, plus Alona guttata (Chydoridae). J Paleolimnol 6:193-197. doi: 10.1007/BF00233071

Jeppesen E, Christoffersen K, Landkildehus F, Lauridsen T, Amsinck SL, Riget F, Søndergaard M (2001) Fish and crustaceans in northeast Greenland lakes with special emphasis on interactions between Arctic charr (Salvelinus alpinus), Lepidurus arcticusand benthic chydorids. Hydrobiologia 442:329-337.doi: 10.1023/A:1017508211819

Lauridsen TL, Jeppesen E, Landkildehus F, Søndergaard M (2001) Horizontal distribution of cladocerans in arctic Greenland lakes – impact of macrophytes and fish. Hydrobiologia 442:107-116. doi: 10.1023/A:1017517919996

Lütken CF (1875) List of Crustacea, known from Greenland. In: Jones TR (ed) Manual and instructions for the Arctic Expedition (vol 2). Pst, London, pp 146-165

Madsen H (1940) A study of the littoral fauna of Northwest Greenland. Meddelelserom Grønland, 124:1-24

Røen UI (1962) Studies on Freshwater Entomostraca in Greenland II. Localities, ecology and geographical distribution of the species. Meddr Groenland 170:1-249

Røen UI (1987) Chydorus arcticus n. sp., a new cladoceran crustacean (Chydoridae: Chydorinae) from the North Atlantic Arctic and Subarctic areas. Hydrobiologia 143:125-130. doi: 10.1007/BF02530272

Røen UI (1988) Remains of early glacial Cladocera from North Greenland.Verhandlungen der Internationalen Vereinigung für theoretische und angewandte Limnologie 32:845–847

Weider LJ, Hobaek A, Crease TJ, Stibor H (1996) Molecular characterization of clonal population structure and biogeography of Arctic apomictic Daphnia from Greenland and Iceland. Mol Ecol 5:107–118. doi: 10.1111/j.1365-294X.1996.tb00296.x

·  Norway:

Aagaard K, Dolmen D (eds) (1996) Limnofauna Norvegica. Katalog over norskferskvannsfauna. Tapirforlag,Trondheim.

Oug E, Brattegard T, Vader W, Christiansen ME, Walseng B, Djursvoll P (2010) In: Kålås JA, Viken Å, Henriksen S, Skjelseth S (eds) Krepsdyr Crustacea. Norsk Rødliste for arter 2010. The 2010 Norwegian Red List for Species Arts data banken, Trondheim, pp 209-221

Schartau AK, Halvorsen G, Walseng B (2007) Northern Lakes Recovery Study (NLRS) – microcrustaceans. Reference conditions, acidification and biological recovery. NINA Rapport 235. NINA, Trondheim

Walseng B (1994) Alona spp. in Norway: Distribution and ecology. Verh Internat Verein Limnol 25:2358-2359