Reptilia · Squamata
Egernia saxatilisCogger, 1960
Black Rock Skink
Photograph by Lando25, CC BY-SA, via Wikimedia Commons
A day-active, omnivorous skink from the Australo-Pacific region, reaching 135 mm snout to vent.
Also called Black Crevice-skink.
Reptilia › Squamata › Scincidae › Egernia
- Grows to
- 135mm
- greatest recorded
- Eats
- Omnivorous
- Active
- Diurnal
- Lives up to
- 8years
Longer than 91% of all skinks anyone has measured.
The bar is the rank itself: its length is the share of the family this animal exceeds. The chart below is the family’s real spread, on a logarithmic scale because body length here runs from 24 to 500 mm. The solid rule is this animal. Every bar is a count of real species, and nothing on this figure is estimated.
What is known
35 sourced facts, each taken from a named scientific dataset. How to read these.
Cited from a dataset unless a row is marked otherwise.
Standing in the world
- Still living
- Extant
- Conservation status
- Least Concern
- Status assessed · the year the Red List last looked
- 2017
The animal itself
- Limbs
- Four legs
- Venomous
- No
- Fangs
- None
- Longest recorded life
- 8years
- Preferred body temperature · chosen in a laboratory gradientmeasured
- 33–34°C91–93 °F
Greer 2005: at least 8
Size
- Length snout to vent · greatest recorded
- 135mm5.25 in
- Length snout to vent · adult female mean
- 106mm4.25 in
- Body mass · greatestcomputed
- 54.57g1.9 oz
- Body mass · adult female, meanmeasured
- 17.5g0.62 oz
- Body mass at hatchingmeasured
- 4g0.14 oz
max 135 mm SVL (Feldman et al. 2016)
computed from length by a family-level allometric equation, not weighed
How it lives
- Diet
- Omnivorous
- Active
- Diurnal
- Where it lives
- Arboreal, saxicolous
- Habitat
- Rocky
- Biome
- Temperate Broadleaf & Mixed Forests
- Region
- Australo-Pacific
- Mainland or island
- Mainland
- Elevation · above sea level
- 1040–1650m
- Range size
- 250,880km²
Omnivorous: mainly Arthropods, 28.6% plants (Greer 2005), invertebrates, some plant material and "occasional" small vertebrates
e.g., Swan 2020 and pers. obs; heliotherm, Robertson and Coventry 2019
Saxicolous, Semi Arboreal / saxicolous (Foster et al. 2018, Shai pers. obs.), rock crevices and fallen timber (Swan 2020)
1040-1650 (Pengilley 1972)
Breeding
- Reproduction
- Viviparous
- Average clutch
- 2eggs
- Eggs or young per clutch
- 1–5eggs
- Mean clutch
- 2eggs
- Clutches a year
- 1per year
- First breeds at
- 12–24months
1-4 (Brown 2012, Robertson and Coventry 2019, Whiting and While 2017), 2 (Pengilley 1972; n=1), 3 (Dave Chapple pers. comm., 27.2.2019 ; n=1)
Naming and history
- Suborder
- Sauria
- Infraorder
- Scincoidea
- Subspecies
- Egernia saxatilis saxatilis COGGER 1960 Egernia saxatilis intermedia COGGER 1960
- Described by
- Cogger
- Moved to another genus · since it was first described
- No
- Described in
- 1960
- Type locality
- Australia
Keeping one
21.5 in × 21.5 in × 21.5 in(54 × 54 × 54 cm)
Minimum length × width × height, for one animal. Bigger is always better.
The standard sizes ground species at 4 × 4 × 2.5 and climbing species at 4 × 2.5 × 4 times snout-vent length.
Recorded both on the ground and climbing, so this is the larger of the two rules in every dimension.
Lives on rock, so stable hard surfaces and basking ledges suit it.
Mindestanforderungen an die Haltung von Reptilien (Sachverständigengutachten), German Federal Ministry for Nutrition, Agriculture and Forestry, Animal Welfare Division, 10 January 1997. The standard states these floor areas are recommendations rather than binding limits.
From this animal’s own snout-vent length of 5.25 in (135 mm), at 4 × 4 × 4 times it, following the German federal welfare standard — how this is worked out.
In a laboratory thermal gradient this species settled at 91–93 °F (33–34 °C).
Preferred body temperature, recorded in a laboratory gradient where the animal could choose freely. A measurement of the animal, not a setting for a thermostat.
Feeding
A prey item should be no wider than the space between the animal's eyes.
Widely used across reptile husbandry references. The stated reason is that the gap approximates the width of the throat, so wider prey is associated with impaction. This is established practice, not a measurement.
7kJ per day
Worked out for an animal of 55 g, the heaviest recorded for Black Rock Skink — so it is the top of the range, not a figure for a particular animal. Weigh yours and the number will be lower.
An upper estimate, not a feeding target, and not veterinary advice. The equation covers only what an animal burns staying alive, so a growing, gravid or recovering animal needs more — and it was measured on wild animals, which move far more than one in an enclosure. Body condition and a vet who knows the species are what a feeding decision should rest on. Where this comes from.
What nobody knows
These are not gaps in our research. No scientific dataset records them for this species — and saying so is information you cannot get from a reference that simply leaves a field out.
- — Length snout to vent · adult male mean
- — Length snout to vent · adult mean
- — Length nose to tail · greatest recorded
- — Female length · mean, nose to tail
- — Length nose to tail · adult male mean
- — Length nose to tail · adult mean
- — Largest female · snout to vent
- — Largest male · snout to vent
- — Largest female · shell length
- — Largest male · shell length
- — Hatchling length · snout to vent
- — Hatchling length · nose to tail
- — Largest juvenile · snout to vent
- — Largest juvenile · shell length
- — Egg length
- — Egg width
- — Body mass · a typical adult
- — Body temperature when active · measured in the wild
- — Eats arthropods
- — Eats vertebrates
- — Eats plant matter
- — How it hunts
- — How the young develop
- — Gestation or incubation
- — Clutches in a year
- — Hatchling length · smallest recorded
- — Hatchling length · largest recorded
- — Age at first breeding · female
- — Mature from · youngest recorded
- — Mature by · oldest recorded
- — Size at maturity · smallest recorded
- — Size at maturity · largest recorded
- — Body temp in the wild · lowest mean recorded
- — Body temp in the wild · highest mean recorded
- — Colour on the back
- — Pattern on the back
- — Pupil
- — Sex decided by
- — Population trend
- — Red List criteria
- — Active season · shortest recorded
- — Active season · longest recorded
- — Density · lowest recorded
- — Density · highest recorded
- — Home range · largest recorded
- — Active in
Others in Scincidae
Take this data
Everything on this page is available as data under CC BY 4.0 — use it freely, credit it, no permission needed.
This species as JSON · the whole dataset
Cite this page
The Reptile & Amphibian Encyclopedia (2026). Egernia saxatilis. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/egernia-saxatilis
@misc{egernia_saxatilis_2026,
title = {Egernia saxatilis},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/egernia-saxatilis}
}Sources
- Meiri, S. (2024). SquamBase — a database of squamate (Reptilia: Squamata) traits. Global Ecology and Biogeography. Public domain (CC0).
- Oskyrko, O. et al. (2024). ReptTraits: a comprehensive dataset of ecological traits in reptiles. Scientific Data. Used under CC BY 4.0.
- Catalogue of Life (dataset 3LR), used under CC BY.