Occurrence of a Sharksucker (Echeneis naucrates) on a Northern River Shark (Glyphis garricki) in a tidal riverine habitat

Remoras (family Echeneidae) are teleost fishes adapted to hitchhiking behaviour on a variety of marine taxa. Three species have been documented in the waters of the Northern Territory, including the Sharksucker (Echeneis naucrates). Sharks are a preferred host for adult E. naucrates. An additional host species, the Northern River Shark (Glyphis garricki), is reported here. A small (178 mm total length) E. naucrates was found attached to a G. garricki in tidal reaches of the West Alligator River in Kakadu National Park in October 2014. This is the first report of an echeneid fish on a shark of the genus Glyphis (‘river sharks’).