A medium sized fish up to 16cm in length. This species was once very common in the lower reaches of both the Murray and Gulf drainages as well as t all coastal streams between about Brisbane and Adelaide. Still common but habitat destruction has significantly reduced its range. Despite this, of all the Australian galaxiids, the Common jollytail has been able to withstand predation as well as habitat destruction better than other galaxiids. This is probably due to its ability to recolonise freshwater following marine larval stage migration. Yet, weirs and habitat alterations inhibit the ability of this species to migrate upstream.

This species feeds on a range of small aquatic and terrestrial insects including crustaceans, insects, molluscs and midge larvae. Migrates down to the edge of river estuaries to spawn. Competes with trout for food source and is also predated upon by trout.