At the time of European settlement, the terrestrial reptile fauna of the Sydney metropolitan area, west and north to the Hawkesbury-Nepean River, consisted of 45 species, based on Australian Museum records, although most regions had between 30-36 species. Skinks and elapid snakes dominated the fauna, with progressively fewer agamid and gekkonid lizards, pygopod and varanid lizards, colubrid snakes, pythons and typhlopid snakes. Most of these species have declined and some have disappeared over the past 140 years, both in suburban environments and adjacent small bushland fragments. Some species disappear rapidly from bushland areas with only minor disturbance, and listings based on records over the past 50 years often underestimate historical faunal diversity. Only large bushland reserves appear to retain the majority of species. Only a small number of skink species are typically retained in suburban environments, although a small number of other lizards and snakes may persist if suitable habitats are retained, and some large snake species may utilise suburban environments adjacent to undeveloped or agricultural areas. Ecological features possessed by the surviving suburban reptile fauna include either a lack of habitat specialisation or a habitat preference for moist environments, high fecundity, a lack of dietary specialisation, and small size. In contrast, a habitat specialisation for sandstone environments (other than caves), stenophagy, low fecundity and large size combined with large home ranges are features commonly possessed by species that have not persisted in suburban environments.