The Alert pigfish was first formally described in 1960 by the New Zealand ichthyologist John Munne Moreland with they type locality given as east of the Otago Peninsula at 45°47'S, 171°7'E.

[3] The genus name is a combination of Alert, the name of the research vessel the holotype was collected on, and ichthys, Greek for "fish", while the specific name honours Alex J.

[4] The Alert pigfish has a relatively long snout with a small terminal mouth.

The overall colour is silvery grey, paler on the lower body and with a dark forward margin to the pectoral fins.

[5] The Alert pigfish is known only from the waters of southern and central New Zealand as far north as the Chatham Rise.