Abstract
This paper focuses on the origin of Trichoptera species in Iceland in light of the island biogeography of caddisflies in the North-Atlantic islands, i.e., Greenland, Svalbard, Iceland, Faroe Islands, Shetland, and Orkney, and adjacent larger regions, Norway and Britain. Three of the 12 recorded species have circumpolar distribution, the other nine are Palaearctic. The number of species declines with the distance from the mainland of Europe and is independent of the island sizes. However, the occurrence of species is stochastic, with only a few species common to the more remote islands—e.g., Iceland has 12 species and the Faroe Islands 20, but only 4 species are common to both islands. Studies on phylogeographic patterns of two species, Potamophylax cingulatus and Apatania zonella, show different history based on genetic markers. Potamophylax cingulatus in Iceland is from a western European lineage, distinct from two eastern and southern European lineages that may have diverged in southern refugia during the glacial periods of the latest Ice Age. The ancestors of the Icelandic population have migrated from the Iberian Peninsula up the west cost of Europe to the Faroe Islands and Iceland. The parthenogenetic A. zonella in Iceland originated near the Bering Strait, and has migrated along two routes, one westward through northern Eurasia and the other eastward through North America and Greenland to Iceland, where the two populations meet. Preliminary phylogeographic studies on two other circumpolar species, Limnephilus fenestratus and L. picturatus indicate possible interchanges between North America and Europe, but due to a low number of samples, it is difficult to state where the Icelandic population came from.
References
Aegisdóttir, H.H. & Thorhallsdóttir, T.E. (2004) Theories on migration and history of the North-Atlantic flora: Areview. Jökull, 54, 1–16.
Andersen, T. & Wilberg-Larsen, P. (1987) Revised check-list of NW European Trichoptera. Entomologica scandinavica, 18, 165–184.
Andrew, R.H. (2014) Orkney caddis (Trichoptera) species list with ecological notes: Part 1. Orkney Field Club Bulletin, 2014, 43–52
Barnard, P. & Ross, E. (2012) The adult Trichoptera (caddisflies) of Britain and Ireland. Handbooks for the Identification of British Insects, 1. Part 17, 192 pp.
Barry, J.R. (1985) The natural history of Orkney. Collins, London, 300 pp.
Böcher, J. (2002) Insekter og andre smådyr—I Grønlands fjeld og ferskvand. Forlaget Atuagkat, Nuuk, 302 pp.
Brochmann, N.C., Gabrielsen, T.M., Nordal, I., Landvik, J.Y. & Elven, R. (2003) Glacial survival or tabula rasa? The history of North Atlantic biota revisited. Taxon, 52, 417–450.
https://doi.org/10.2307/3647444
Buckland, P.C. & Panagiotakoulu, E. (2010) Reflections on North Atlantic Island Biogeography: a Quaternary entomological view. Annales Societatis Scientiarum Færoensis Supplimentum, 52, 181–209.
Buckland, P.C., Perry, D.W., Gíslason, G.M. & Dugmore, A.J. (1986) The pre-Landnám fauna of Iceland: A palaeoontological contribution. Boreas, 15, 173–184.
https://doi.org/10.1111/j.1502-3885.1986.tb00081.x
CLIMAP (1976) The surface of the ice age earth. Science, 191, 1131–1144.
https://doi.org/10.1126/science.191.4232.1131
Corbet, P.S. (1966) Parthenogenesis in caddisflies (Trichoptera). Canadian Journal of Zoology, 44, 981–982.
https://doi.org/10.1139/z66-100
Crosskey, R.W. (1965) A new species of Simulium (Eusimulium) from St. Helena Island, South Atlantic (Diptera: Simuliidae). Proceedings of the Royal Entomological Society of London B, 34, 33–37.
https://doi.org/10.1111/j.1365-3113.1965.tb01646.x
Curtis, J. (1834) Description of some hitherto nondescript British species of mayflies of anglers. The London and Edinburgh Philosophical Magazine and Journal of Science, 3 (4), 120–125, 212–218.
https://doi.org/10.1080/14786443408648304
Downes, J.A. (1988) The post-glacial colonization of the North Atlantic islands. Memoirs of the Entomological Society of Canada, 144, 55–92.
https://doi.org/10.4039/entm120144055-1
Edington, J.M. & Hildrew, A.G. (1995) A Revised Key to the Caseless Caddis Larvae of the British Isles: A Key with Ecological Notes. Freshwater Biological Association, Ambleside, Scientific Publication No. 53, 134 pp.
Elven, H. & Andersen, T. (2019). Nøkkel til vårfluefamilier. Artsbanken. Available from: https://www.artsdatabanken.no/Pages/262183?Key=1518696646 (accessed 4 March 2019)
Forsslund, K.H. (1930) Zwei neue Apatelia-Arten (Trichoptera, Limnophiliden). Entomologisk Tidskrift, 51, 216–218.
Forsslund, K.H. & Tjeder, B. (1942) Catalogus insectorum Sueciae. II. Trichoptera. Opuscula Entomologica, 7, 93–106.
Friedrich, W.L., Símonarson, L.A. & Heie, O.E. (1972) Steingervingar í millilögum í Mókollsdal (English summary: Tertiary fossils from Mókollsdalur, NW-Iceland). Náttúrufræðingurinn, 42, 4–17.
Geirsdóttir, Á., Miller, G.H., Axford, Y. & Ólafsdóttir, S. (2009) Holocene and latest Pleistocene climate and glacier flutctuations in Iceland. Quaternary Science Reviews, 28, 2107–2118.
https://doi.org/10.1016/j.quascirev.2009.03.013
Geirsdóttir, Á., Miller, G.H., Larsen, D.J. & Ólafsdóttir, S. (2013) Abrupt Holocene climate transitions in the northern North Atlantic region recorded by synchronized laustrine records in Iceland. Quaternary Science Reviews, 71, 48–62.
https://doi.org/10.1016/j.quascirev.2013.03.010
Gíslason, G.M. (1977) Aspects of the biology of Icelandic Trichoptera, with comparative studies on selected species from Northumberland, England. Ph.D. Dissertation, Department of Zoology, University of Newcastle upon Tyne, 412 pp.
Gíslason, G.M. (1981) Distribution and habitat preferences of Icelandic Trichoptera. In: Moretti, G.P. (Ed.), Proceedings of the 3rd International Symposium on Trichoptera. Dr. W. Junk Publishers, The Hague, Series Entomologia. 20, pp. 99–109.
https://doi.org/10.1007/978-94-009-8641-1_14
Gíslason, G.M. (2005) The origin of the freshwater fauna of the North-Atlantic Islands. Present distribution in relation to climate and possible migration routes. Verhandlungen der Internationale Vereinigung für Theoretische und Angewandte Limnologie, 29, 198–203.
https://doi.org/10.1080/03680770.2005.11901995
Gíslason, G.M., Hannesdóttir, E.R., Munoz, S.S. & Pálsson, S. (2015) Origin and dispersal of Potamophylax cingulatus (Steph.) (Trichoptera: Limnephilidae) in Iceland. Freshwater Biology, 60, 387–394.
https://doi.org/10.1111/fwb.12501
Heezen, B.C. & Tharp, M. (1963) The Atlantic floor. In: Löve, A. & Löve, D. (Eds.), North Atlantic Biota and Their History. Pergamon Press, Oxford, pp. 21–27.
Hewitt, G. (2000) The genetic legacy of the Quaternary ice ages. Nature, 405, 907–913.
https://doi.org/10.1038/35016000
Hrafnsdóttir, Th. (2005) Diptera 2 (Chionomidae). Zoology of Iceland, 3 (48), 1–169.
King, J.J.F.X. (1890) Neuroptera from the island of Unst. Entomologist’s Monthly Magazine (2), 1 (26), 176–180.
Kornobis, E., Pálsson, S., Kristjánsson, B.K. & Svavarsson, J. (2010) Molecular evidence of the survival of subterranean amphipods (Arthropoda) during Ice Age underneath glaciers in Iceland. Molecular Ecology, 19, 2516–2530.
https://doi.org/10.1111/j.1365-294X.2010.04663.x
McLachlan, R. (1866) Note respecting a species of Apatania. Entomologist’s Monthly Magazine, 3, 113.
McLachlan, R. (1871) Notes on the Trichoptera of Zetterstedt’s “Insecta Lapponica,” in connection with the nomenclature of British species. Entomologist’s Monthly Magazine, 7, 281–282.
McLachlan, R. (1875) A monographic revision and synopsis of the Trichoptera of the European fauna, Part 2. John van Voorst, London, pp. 47–108.
https://doi.org/10.5962/bhl.title.28556
Naturhistoriska Riksmusset (2018) Check-list of Norwegian Trichoptera. Available from: http://www2.nrm.se/en/trichopteranorway.html (accessed 8 May 2018)
Nilsson, A. (Ed.) (1996) Aquatic Insects of North Europe. A Taxonomic Handbook. Apollo Book, Stenstrup, Denmark.
Nilsson, A. (Ed.) (1997) Aquatic Insects of North Europe 2. A Taxonomic Handbook. Apollo Book, Stenstrup, Denmark.
Ólafsson, E. (1991) Íslenskt skordýratal. (A checklist of Icelandic insects). Icelandic Institute of Natural History report no. 17, 69 pp. [In Icelandic, English summary]
Pálsson, S., Lecaudey, L.A. & Gíslason, G.M. (2016) Phylogeographic origin of Apatania zonella (Trichoptera) in Iceland. Freshwater Science, 35, 65–79.
https://doi.org/10.1086/684850
Pennington, M. (2018a) Trichoptera. Available from: http://www.nature-shetland.co.uk/entomology/caddis.htm (accessed 8 May 2018)
Pennington, M. (2018b) Diptera. Available from: http://www.nature-shetland.co.uk/entomology/diptera.htm (accessed 8 May 2018)
Peterson, B.V. (1977) The black flies of Iceland (Diptera: Simuliidae). Canadian Entomologist, 109, 449–472.
https://doi.org/10.4039/Ent109449-3
Pinder, L.C.V. (1978) A Key to Adult Males of British Chironomidae.Vol. 1–2. Freshwater Biological Association, Ambleside, Scientific Publication No. 37, 169 pp.
Raastad, J.E. & Solem, J.O. (1989) Autogeny as successful reproductive strategy in high altitude blackflies (Diptera, Simuliidae). Annales de Limnologie, 25, 243–249.
https://doi.org/10.1051/limn/1989026
Stephens, J. (1836–1837) Illustrations of British Entomology; or a Synopsis of Indigenous Insects: Containing their Generic and Specific Distinctions; with an Account of their Metamorphoses, Times of Appearance, Localities, Food, and Economy, as far as Practicable. Mandibulata. Vol. VI. Baldwin and Cradock, London.
Tobias, W. (1981) Eine neue Apatania-Art aus Norwegen (Trichoptera: Limnephilidae). Entomologische Zeitschrift, 91, 62–65.
Wallace, I.D., Wallace, B. & Philipson, G.N. (1990) A Key to the Case-bearing Caddis Larvae of Britain and Ireland. Freshwater Biological Association, Ambleside, Scientific Publication No. 51, 237 pp.
Zetterstedt, J.W. (1840) Fauna Insectorum Lapponica. Vol. 5. Leipzig.