Sillaginodes

The King George whiting (Sillaginodes punctatus), also known as the spotted whiting or spotted sillago, is a coastal marine fish of the smelt-whitings family Sillaginidae. The King George whiting is endemic to Australia, inhabiting the south coast of the country from Jurien Bay, Western Australia to Botany Bay, New South Wales in the east. The King George whiting is the only member of the genus Sillaginodes and the largest member of the smelt-whiting family Sillaginidae, growing to a length of 72 cm and 4.8 kg in weight. The species is readily distinguishable from other Australian whitings by its unique pattern of spots, as well as its highly elongate shape. King George whiting are often found in bays and protected waterways over sand and seagrass beds, also venturing out onto deep continental shelf reefs during adulthood. The species is a benthic carnivore, consuming a variety of crustaceans, polychaete worms, molluscs and fish. The King George whiting forms the basis of one of southern Australia's most important commercial fisheries, reportedly worth over five million Australian dollars per year. The species is also heavily targeted by recreational anglers, who value the whiting for its sporting and eating qualities. The King George whiting is the only species nested in the genus Sillaginodes, which itself is in the family Sillaginidae, containing all the smelt whitings. The Sillaginidae are part of the Percoidei, a suborder of the order Perciformes.The King George whiting was first officially named by Cuvier in 1829 as Sillago punctata, based on an individual taken from King George Sound in Western Australia. In 1861, Theodore Gill created the monotypic genus Sillaginodes based on a number or morphological characteristics and assigned S. punctatus to it. A number of synonyms have been applied after the initial correct naming, apparently due to Cuvier not designating a holotype, or it being lost. A lectotype was finally designated by McKay in 1985. The species has a variety of common names (many now obsolete), with the most common, “King George whiting”, taken from the name of the body of water where the initial description was made. It is also often called the spotted whiting in reference to its obliquely positioned bars of brown spots, with other names used in markets, especially outside of Australia. The King George whiting has the same overall profile as the rest of the sillaginid fishes, an elongate, slightly compressed body with a tapering head and terminal mouth. The genus Sillaginodes is distinguished by a first dorsal fin with twelve or thirteen spines and the second dorsal fin with a single spine and 25 to 27 soft rays. The vertebrae number between 42 and 44 in the genus. The King George whiting is the only member of the genus Sillaginodes and is further distinguished from any other possible taxa assigned to that genus by a number of distinct anatomical features. It is the largest of the Sillaginid fishes with 129 to 147 lateral line scales, and like all fishes in the family is best distinguished by the shape of its swim bladder. In plan view, the swim bladder has a land slug-like appearance, with a posteriorly tapering extension and two anterolateral extensions or ‘horns’. There are no duct-like processes on the ventral surface unlike taxa in the genus Sillago. In situations where identification is needed quickly, the colour of the King George whiting is also very distinctive, with a pale golden brown to olive brown top colour and white to silver colour on its underside. The species also as distinct obliquely positioned rows of brown spots running the length of its body, which are apparent to see even after removal from the water and after death. The caudal, anal and pectoral fins are usually a light brown, with some having olive green caudal fins. It is the largest member of Sillaginidae, growing to a maximum length of 72 cm long and 4.8 kg in weight. The King George whiting is endemic to Southern Australia, ranging lower Western Australia, South Australia, Victoria and occasionally even lower New South Wales. The westernmost reported capture was in Jurien Bay and the furthest east King George whiting have been reported from is Botany Bay in New South Wales (although this appears to be a rare occurrence). King George whiting are most commonly found in tidal bays, estuaries and creeks along the coast of the mainland and numerous islands scattered throughout the species’ range.There is a distinct difference in habitat between the adult and juvenile fish, with the juveniles more inclined to inhabit shallower waters in protected bays, creeks and estuaries. A favourite habitat of young fish appears to be Zostera and Posidonia seagrass beds in protected bays, apparently using the seagrass as protection and for foraging purposes.Juveniles tend to form schools of varying sizes, occasionally schooling with other species, including other members of the family Sillaginidae. Adults tend to be solitary and found in deeper water in a range of habitats including bays, offshore surf gutters, broken bottom and deep reef, also venturing into shallower water on occasion.