The absolute growth pattern of Matuta lunaris (Forskål) is assessed, based on moult increment data and analyses of size frequency distributions. Both sexes show determinate growth with maturity occurring at the terminal puberty moult. However, Matuta lunaris is unusual as the sexes differ markedly in their growth patterns. Males mature at a larger size than females and grow to a larger maximum size. Male growth is characterized by relatively constant moult increments and an unknown and possibly variable number of immature instars with widely overlapping size ranges. In contrast, female growth is characterized by relatively large moult increments and a fixed number of instars, each with restricted size ranges.