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 Hydrogamasus littoralis ( Canestrini & Canestrini, 1881 ) Synonym: Gamasus littoralis Canestrini & Canestrini, 1881 ( original designation ) Type material: Holotype : One specimen deposited at Instituto Sperimentale per la Zoologia Agraria ( Castilho et al. 2016 ; GBIF 2022 ). Type locality: Italy : Lido de Venezia ( Canestrini & Canestrini 1881 ; Castilho et al. 2016 ; GBIF 2022 ). Geographical distribution: Western Europe ( GBIF 2022 ). Distribution in Portugal : North: Leça da Palmeira, Cabo do Mundo, Vila Praia da Âncora, and Moledo beaches ( Costa-Garcia 2018 ). Ecological notes: Marine, intertidal, barnacle epibiont ( Costa-Garcia 2018 ; Halbert 1920 ). Remarks: This species is considered marine, however, its status as truly aquatic should be furtherly checked that it is an active species in all its life stages in water, as well as its breeding.