Reptilia · Squamata
Varanus scalarisMertens, 1941
Banded Tree Monitor
Identification not confirmed. One observer recorded this animal as this species and no one has since agreed, so the photograph may show a different animal.
Photograph by Karl Tattersall, CC BY-SA, via iNaturalist
A day-active, meat-eating monitor lizard from the Australo-Pacific region, reaching 268 mm snout to vent.
Also called Spotted Tree Goanna, Spotted Tree Monitor.
Reptilia › Squamata › Varanidae › Varanus
- Grows to
- 268mm
- greatest recorded
- Eats
- Carnivorous
- Active
- Diurnal
- Lives up to
- 20years
Longer than only 21% of all monitor lizards 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 116.4 to 1,570 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
38 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
- 2014
The animal itself
- Limbs
- Four legs
- Fangs
- None
- Longest recorded life
- 20years
- Preferred body temperature · chosen in a laboratory gradientmeasured
- 36.7°C
- Body temperature when active · measured in the wild
- 35.2°C95 °F
- Body temp in the wild · mean, when active
- 31.5–38.9°C89–102 °F
Mendyk 2015
mean body temperature of active individuals in nature
body temperature of active animals in nature
Size
- Length snout to vent · greatest recorded
- 268mm10.5 in
- Length snout to vent · adult female mean
- 205.6mm8 in
- Largest female · snout to vent
- 205.6mm8 in
- Hatchling length · snout to vent
- 63mm2.5 in
- Largest juvenile · snout to vent
- 63mm2.5 in
- Body mass · greatestcomputed
- 358.1g12.6 oz
- Body mass at hatchingmeasured
- 4.2g0.15 oz
max 268 mm SVL (Feldman et al. 2016)
snout-vent length; the source column mixes this with straight carapace length
computed from length by a family-level allometric equation, not weighed
How it lives
- Diet
- Carnivorous
- How it hunts
- Mixed
- Active
- Diurnal
- Where it lives
- Arboreal, terrestrial
- Habitat
- Forest, Savanna, Shrubland
- Biome
- Tropical & Subtropical Grasslands, Savannas & Shrublands
- Region
- Australo-Pacific
- Mainland or island
- Mainland
- Elevation · above sea level
- 20–30m
- Range size
- 1,203,618km²
invertebrates and lizards and birds (e.g., Arbuckle 2009), arthropods, lizards, mammals and birds (Bennett 1995), insects and lizards (Auliya and Koch 2020)
active foraging (e.g., Brown and Nagy 2007, Clemente et al. 2009)/ both (Sweet 2007, p399), ambush (Weijola 2010)
e.g., Auliya and Koch 2020
Arboreal and Terrestrial (see Sources (general) column)
Breeding
- Reproduction
- Oviparous
- Average clutch
- 5.85eggs
- Eggs or young per clutch
- 3–12eggs
- Mean clutch
- 4–7.7eggs
- Clutches a year
- 1per year
mean 4 (Du et al. 2014), max 8 (Bennett 1995)
Naming and history
- Suborder
- Sauria
- Infraorder
- Anguimoprha
- Subspecies
- No
- Described by
- Mertens
- Moved to another genus · since it was first described
- No
- Described in
- 1941
- Type locality
- Australia
Keeping one
3 ft 6 in × 3 ft 6 in × 3 ft 6 in(107 × 107 × 107 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.
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 10.5 in (268 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 98 °F (36.7 °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.
37kJ per day
Worked out for an animal of 358 g, the heaviest recorded for Banded Tree Monitor — 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 male · snout to vent
- — Largest female · shell length
- — Largest male · shell length
- — Hatchling length · nose to tail
- — Largest juvenile · shell length
- — Egg length
- — Egg width
- — Body mass · a typical adult
- — Body mass · adult female, mean
- — Eats arthropods
- — Eats vertebrates
- — Eats plant matter
- — How the young develop
- — Gestation or incubation
- — Clutches in a year
- — First breeds from · youngest recorded
- — First breeds by · oldest recorded
- — 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
- — Venomous
- — 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 Varanidae
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). Varanus scalaris. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/varanus-scalaris
@misc{varanus_scalaris_2026,
title = {Varanus scalaris},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/varanus-scalaris}
}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.