Overview of sampling localities (red dots) with the ecoregions in italics. Localities 3 and 5 are located within the cities Mbanza-Ngungu and Kisantu, respectively. The inset shows the Lower Congo region on the African continent. Sampling localities: 1, Tondé Estuary near Muanda (05°57′35.9″S 12°21′58.4″E); 2, Muila Kaku, mangroves near Lower Congo River (05°59′33″S 12°35′03.2″E); 3, Ndimba Leta ponds, Mbanza-Ngungu, in between the Lunzadi and Lukasi rivers of which the latter flows into the Kwilu and Likunga (05°15′10″S 14°51′24″E); 4, Pond near Kila Kindinga and Lukasi river (5°29′7″S 14°53′4″E); 5, Inkisi River, off the Jardin botanique de Kisantu (05°08′02″S 15°03′52″E); 6, Mvuazi River, Inkisi (5°19′S 15°7′E); 7, Mbola River near Tshianya village (05°52′09.8″S 12°39′52.6″E); 8, Congo River near Nganda Flash station (06°02′01.8″S 12°31′48.2″E), 9, Muila Nzenze, Kibamba village, mangroves near Congo River (06°00′06.8″ S 12°40′27″ E). Rivers in blue.