New additions to the freshwater gastropod fauna (Gastropoda: Hydrobiidae, Lymnaeidae) of Morocco Author Mabrouki, Youness Sidi Mohamed Ben Abdellah University, Faculty of Sciences Dhar El Mehraz, Biotechnology, Conservation and Valorisation of Natural Resources laboratoy, Fez, Morocco. E-mail: younes _ mab @ hotmail. fr Author Taybi, Abdelkhaleq Fouzi Sidi Mohamed Ben Abdellah University, Faculty of Sciences Dhar El Mehraz, Biotechnology, Conservation and Valorisation of Natural Resources laboratoy, Fez, Morocco. E-mail: taybiaf @ gmail. com Author Glöer, Peter Schulstr. 3, D- 25491 Hetlingen, Germany. E-mail: gloeer @ malaco. de Corresponding author: Peter Glöer text Ecologica Montenegrina 2020 2020-05-22 31 40 44 http://dx.doi.org/10.37828/em.2020.31.8 journal article 10.37828/em.2020.31.8 2336-9744 13231659 Mercuria gauthieri Glöer, Bouzid & Boeters, 2010 ( fig. 4 ) Distribution: This recently described species was previously known only from Algeria , where it was confined to the westernmost part of the Algerian coast ( Glöer 2019 ; Glöer et al. 2010 ). We reported for the first time in Morocco , where it is confined to the easternmost of the country. Indeed, the species was found in the catchment area of the Nador lagoon, the massif mountain of Gourougou and the wetland of the Moulouya River mouth at Saidia ( fig. 1 ). Sampling site: Zebda spring ( 35°03'55.1" N 2°21'16.2" W ) ; affluent of Zebda spring ( 35°05'28.5" N 2°21'02.7" W ) ; Azouagh River at Zegangan ( 35°8'20.688" N 3°1'24.247" W ) ; Selouan River at Sidi Ali ( 35°4'36.700" N 2°55'29.100" W ) ; Selouan River at La'azib ( 35°3'6.199" N 2°57'46.598" W ) ; Moulouya River at Safsaf ( 34°54'27.530" N 2°38'8.860" W ) ; Mariouari River ( 35°18'21.600" N 2°58'38.900" W ) ; Chebbak spring ( 35°05'18.2" N 2°21'04.0" W ) ; Rio de Oro River ( 35°17.2483' N , 2°56.6283' W ) ; Izerouan River ( 35°9.8333' N , 3°6.6' W ) ; Ouzej River at Aroui ( 35°0.3634' N , 2°59.5133' W ) ; Cherarba Ponds at Saidia ( 35°6.3116' N , 2°20.75' W ) . Habitat: The species can be found in a wide range of habitats and in different physicochemical conditions of the water. It was collected from natural and artificial watercourses of low altitudes, sometimes highly charged with organic matter as Selouan River ( fig. 10 ), high altitude springs and finally from slightly brackish ponds alongside of the Mediterranean coast. Associated species: Physella acuta , Ancylus fluviatilis , Lymnaea truncatula and Planorbarius metidjensis (Forbes, 1838) .