Along the coastal lowlands of Australia, the skink has been observed laying eggs and giving birth to live young for reproduction.

Individuals of the species in the lowlands lay eggs (oviparous), while its neighbors to the north in the mountains are almost exclusively giving birth to live young (viviparous).

[10] Phylogenetic analysis in 2003 showed that the closest sister taxa of Saiphos equalis are Coeranoscincus reticulatus and members of the genus Ophioscincus.

[15] Lizards from high elevation sites (greater than 1,000 m (3,300 ft)) in north-eastern New South Wales are viviparous, while low-elevation populations from northern and southern in New South Wales exhibit short-period oviparity, an intermediate between viviparity and typical oviparous behaviors.

In the northernmost coastal region of New South Wales, the lizards have relatively long incubation periods (approximately 15 days), and the eggshells are thicker.