There are a large number of gudgeon species native to Australia however by eliminating those found only in the tropics and those limited to altitudes below 700 metres (Dunmore is above 1300 metres) left us with only six species. The records of sightings in the “Atlas of Living Australia” decreased this number to two, being the the western carp gudgeon (Hypseleotris klunzingeri) and the flathead Gudgeon (Philypnodon grandiceps)

Both are fairly similar in general appearance, being small and laterally compressed with two separate and distinct dorsal fins and a truncate to slightly rounded tail. The most obvious difference being that the Flathead gudgeon has a broad and flat head with a large mouth.

The western carp gudgeon are found in a number of East Coast drainages, from the Hunter River system in northern New South Wales to the Fitzroy River system in central Queensland. Maximum length 70mm; usually around 40mm. The upper portion of their dorsal fins often develops an orange-red colour, bordered by a bluish-white stripe, which is particularly noticeable in breeding males. The back is yellowish-grey to greenish-brown and the scales of the upper sides and back have darker edges.

The Flathead gudgeon occurs from coastal rivers of the Mackay region, Queensland to the Murray River, South Australia. It is also known from inland waters of the Murray-Darling drainage from Lachlan River, New South Wales to the Murray River, South Australia. It can also be found in northern Tasmania.

Colouration varies from black, brown, grey or reddish to greenish-brown overall. There are faint dark blotches on the back behind the head and below the dorsal fins. The sides of the body have irregular faint brown markings and thin bands on the lower sides and yellowish belly. There is a dark spot on the caudal fin base and several dark lines radiating from the eyes. The caudal and dorsal fins have alternating grey and orange bands. Maximum length of 110 mm, usually about 55mm.

Muddlers imitate gudgeon quite well and our April Fly of the month, the Gambusia, should also be a close imitation. Basically any fly imitating a small brown baitfish should work. American sculpin patterns using ‘sculpin helmets’ are a great imitation of the Flathead gudgeon.