The black upper side has a pattern of broken-up pale scales that appear as white flecks.
The underside of the skink is slightly orange and the ventral sides of the tail and throat are white with scattered black markings.
[2] E. saxatilis is diurnal and is the most active during the morning and later afternoon and spends the majority of its time sheltered in rock crevices.
[5] These skinks prefer permanent shelter for habitat including rock crevices beneath boulders and sometimes timber on rocky outcrops.
Large crevices allow for a larger family to occupy them; however, they are at higher risk of attack from predators including snakes.
[6] Black rock skinks show strong attachment to their permanent shelters because most of their activity, basking and foraging takes place in the immediate area around this site.
[9][10] Shelter sites range in preferability due to the amount of sun exposure they receive and thus vary in their thermal properties.
An interspecific hierarchy for the most thermally-superior shelters exists based on the physical size of the lizard family who wishes to occupy it.
[9] Intruding lizards use several visible cues as indicators of the size of the inhabitant before they invade the crevice and start a confrontation.
As mentioned previously, E. saxatilis has a complex familial structure in which juveniles remain under parental care in stable nuclear groups for the first several years of their life.
Furthermore, the probability that a juvenile is found in the same crevice as a conspecific adult is correlated with the increasing size of the lizard species.
When this occurs, the smaller lizard is more likely to retreat than continue to invade the crevice and risk injury or death in a confrontation with the larger conspecific adult.
In a similar way to mammals, the familial group structure of E. saxatilis may affect the threat associated with encountering a juvenile individual when the intruding species is smaller.
[3][6] Juvenile lizards who are not in family groups are not forced into less preferable habitats though, in terms of thermoregulatory advantages.
Black rock skink recognize their family groups based on prior association and not how genetically related the other lizards are to themselves.
Kin discrimination is important for juvenile skinks to be able to stay within their own territory and avoid dangerous adults.
The small “nuclear families” live in the same permanent shelter and the parents protect their infants from infanticidal conspecifics in this way.
Solitary juvenile lizards are at higher risk of infanticide because of their lack of parental protection and must take advantage of smaller crevices that adults and families would be unable to utilize.
The species is locally abundant, but distribution is severely fragmented and the number of adults appears to be decreasing.
[12] The logging of eucalypts in southeastern Australia has caused a shift in the forest composition from a mixed population of young and old vegetation to an abundant amount of regrowing plants and trees.
However, Egernia saxatilis is predominately a log-basking species and features of regrowth including thicker regenerating vegetation and high stem density prevent adequate sun exposure for these basking lizards.