Checklist of water mites from mainland Portugal and its archipelagos Author Cantallo, Harold 0000-0001-7005-6462 Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos, s / n, 4450 - 208, Matosinhos, Porto, Portugal. & https: // orcid. org / 0000 - 0001 - 7005 - 6462 Author Gomes, Nuno 0000-0002-5513-6875 Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos, s / n, 4450 - 208, Matosinhos, Porto, Portugal. & Aquamuseu do Rio Minho, Vila Nova de Cerveira, 4920 - 290, Portugal. & https: // orcid. org / 0000 - 0002 - 5513 - 6875 Author Antunes, Carlos 0000-0003-2294-6174 Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos, s / n, 4450 - 208, Matosinhos, Porto, Portugal. & Aquamuseu do Rio Minho, Vila Nova de Cerveira, 4920 - 290, Portugal. & https: // orcid. org / 0000 - 0003 - 2294 - 6174 Author Martins, Duarte 0000-0003-3736-5743 Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos, s / n, 4450 - 208, Matosinhos, Porto, Portugal. & Faculdade de Ciências, Universidade do Porto, rua do Campo Alegre s / n, 4169 - 007 Porto, Portugal & https: // orcid. org / 0000 - 0003 - 3736 - 5743 Author Costa, Dimítri De Araújo 0000-0002-5399-2483 Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Terminal de Cruzeiros do Porto de Leixões, Avenida General Norton de Matos, s / n, 4450 - 208, Matosinhos, Porto, Portugal. & Aquamuseu do Rio Minho, Vila Nova de Cerveira, 4920 - 290, Portugal. & https: // orcid. org / 0000 - 0002 - 5399 - 2483 text Zootaxa 2022 2022-11-28 5213 4 336 370 journal article 198868 10.11646/zootaxa.5213.4.2 bf19faf6-6e2f-4f68-83c2-79c95be93fa0 1175-5326 7381432 685D4DC1-0C1E-4E76-BEEE-E54749603695 Eylais extendens ( Müller, 1776 ) Synonyms: Hydrachna extendens Müller, 1776 ( original designation ); Eylais undulosa Koenike, 1897 ; Eylais muelleri Koenike, 1897 ; Eylais limnophila Piersig, 1899 ; Eylais soari Piersig, 1899 ; Eylais similis Thon, 1899 ; Eylais tenera Thon, 1899 ; Eylais mosquensis Croneberg, 1899 ; Eylais unisinuata Croneberg, 1902 ; Eylais instabilis Halbert, 1903 ; Eylais similis gibberipons Viets, 1910; Eylais sugambra Koep, 1911 ; Eylais thienemanni Koenike, 1911 ; Eylais monofissa Szalay, 1934 ; Eylais szalayi Husiatinschi, 1939 Type material: Unknown, possibly lost. Type locality: Denmark (probably surroundings of Copenhagen) or Norway ( Müller 1776 ) . Geographical distribution: Western Palaearctic ( Davids et al. 2006 ). Distribution in Portugal : Centre: Beira Litoral, Alcobaça municipality; South: Alentejo, Guadiana River-between Serpa and Beja municipalities ( Lundblad 1956 ; Valdecasas 1988 ). Ecological notes: In oligotrophic and euritrophic slow-moving waters and sensitive to high electrolyte concentrations (absent in brackish water) ( Davids et al. 2006 ), present in dead twigs, plants, such as grasses, Alisma spp. , Myriophyllum spp. and Scirpus spp. ( Lundblad 1956 ) ; Larval insects hosts: parasitic of 26 different water beetle species from families Dytiscidae , Haliplidae , Noteridae , Lacophilidae, and Hydrophilidae ( Davids et al. 2006 ) .