LARVAL DEVELOPMENT OF KING-GEORGE WHITING, SILLAGINODES-PUNCTATA, SCHOOL WHITING, SILLAGO-BASSENSIS, AND YELLOW FIN WHITING, SILLAGO-SCHOMBURGKII (PERCOIDEI, SILLANGINIDAE), FROM SOUTH-AUSTRALIAN WATERS

The larval development of Sillaginodes punctata, Sillago bassensis, an d Sillago schomburgkii is described based on both field-collected and laboratory-reared material. Larvae of the three species can be separat ed based on a combination of pigment and meristic characters, includin g extent and appearance of dorsal midline pigment, lateral pigment on the tail, presence or absence of pigment above the notochord tip, myom ere number, extent and timing of gut coiling, and size at flexion. The most useful meristic character across the range of specimens was numb er of myomeres. Sillaginodes punctata with 42-45 myomeres are easily d istinguished from Sillago schomburgkii with 36-38, and from S. bassens is with 32-35. The timing of gut coiling and its subsequent effect on anus position differed both among the three species examined here and from that previously reported for sillaginid larvae in general. Timing of gut coiling and extent of anus migration are not useful characters for the identification of temperate Australian sillaginids at the fam ily level but are useful on a specific level. Possible implications of the development of the gut to diet are discussed. Based on the presen ce of larvae, all three species spawn in South Australian waters. No l arvae of a fourth sillaginid species, S. flindersi, were found during the study. South Australia is the western distributional limit for S. flindersi and it does not appear to spawn in the area.