Sillago ciliata

The sand whiting (Sillago ciliata), also known as the summer whiting, yellowfin whiting or blue-nose whiting, is a common species of coastal marine fish of the family Sillaginidae, the smelt-whitings. It is a slender, slightly compressed fish that is very similar to other species of Sillago, with detailed spine, ray and lateral line scale counts needed to distinguish the species between its nearest relative Sillago analis. The sand whiting is distributed along the east coast of Australia from Cape York south to Tasmania, as well as Lord Howe Island and New Caledonia in the Pacific Ocean. The sand whiting commonly inhabits shallow sandy substrates in bays, estuaries and surf zones where it preys on polychaete worms, small crustaceans and bivalve molluscs. Reproduction in the species is variable over its range, generally spawning twice between September and April. Young fish inhabit shallow sand flats, both along the coast and well into the upper reaches of estuaries. First described in 1829, the species has long been prized as a table fish and is commonly sought by both recreational and commercial fishermen in New South Wales and Queensland. The sand whiting fishery is most prolific in southern Queensland and northern New South Wales where the species is most abundant, often caught along other species of whiting in estuaries and from beaches. Due to its importance as a commercial fish, substantial research has been carried out on the species, especially feasibility studies involving the use of sand whiting in aquaculture. The sand whiting belongs to the genus Sillago, a division of the smelt whiting family Sillaginidae containing 29 individual species. The Sillaginidae are in the suborder Percoidei, a division of the Perciformes. The species was first identified and named by the French naturalist Georges Cuvier in 1829 after receiving a specimen that was listed as having been collected in the 'Southern seas'. This holotype specimen was apparently taken near the coastline of Tasmania, Australia. Four junior synonyms were subsequently placed on the species, with Castelnau applying both S. insularis and S. terra-reginae, Thiollière applying S. diadoi and Whitley S. ciliata diadoi to the species. All of these names are invalid under the ICZN nomenclature rules, which states that the first correct naming is the one to be used. Many of these synonyms were applied due to confusion over S. ciliata and the nearly identical, closely related species S. analis. The species was also misidentified as S. gracilis, a synonym of S. maculata, the trumpeter whiting; and also S. bassensis, the southern school whiting. S. ciliata is most commonly called the 'sand whiting' in reference to its preference for sandy substrates compared to some members of the genus which prefer muddy, silty, or grassy substrates. Other common names include the 'blue-nose whiting' in reference to the colour of the nose in fish of larger sizes, and 'summer whiting', a name often applied to S. analis as well. This name is applied to these species as they move from deeper offshore waters into shallow beach and estuarine waters in summer, where they become a target for recreational fishers. The sand whiting has a very similar profile to other members of the genus Sillago, with a slightly compressed, elongate body tapering toward the terminal mouth. The dorsal fin is in two parts, the first made of feeble spines and the second of soft rays headed by a single feeble spine, while the ventral profile is straight. The species is known to grow to a maximum size of 51 cm and around 1.25 kg weight. The fin anatomy is highly useful for identification purposes, with the species having 11 spines in the first dorsal fin, with one spine and 16 or 18 soft rays on the second dorsal fin. The anal fin has two spines with 15 to 17 soft rays posterior to the spines. Lateral line scales and cheek scales are also distinctive, with sand whiting possessing 60 to 69 lateral line scales and cheek scales positioned in 3-4 rows, all of which are ctenoid. The amount of vertebrae are also diagnostic, having 32 to 34 in total. The swim bladder has rudimentary tubulesprojecting anteriorly and a series laterally that diminish in size and become sawtooth-like posteriorly. The posterior extension is a single, tapering projection that extends well into the caudal region. A duct like process extends from the ventral surface to the urogenital opening. Swim bladder morphology is useless when determining between S. ciliata and S. analis, as they are nearly identical.