The fin anatomy is highly useful for identification purposes, with the species having 10 to 12 spines in the first dorsal fin, with one spine and 18 or 19 soft rays on the second dorsal fin. The anal fin has two spines with 18 to 20 soft rays posterior to the spines. Lateral line scales and cheek scales are also distinctive, with southern school whiting possessing 63 to 70 lateral line scales and cheek scales positioned in 3–4 rows, all of which are ctenoid. The amount of vertebrae are also diagnostic, having 33 to 35 in total. The swim bladder has a short, blunt anterior median projection with no posterior projection.