Reptilia · Squamata
Lanthanotus borneensisSteindachner, 1878
Borneo Earless Monitor
Photograph by Chien C. Lee, Wild Borneo Photography, CC BY-SA, via Wikimedia Commons
A nocturnal, meat-eating lizard from the Oriental region, reaching 220 mm snout to vent.
Reptilia › Squamata › Lanthanotidae › Lanthanotus
- Grows to
- 220mm
- greatest recorded
- Eats
- Carnivorous
- Active
- Nocturnal
- Lives up to
- 7.8years
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
- Endangered
- Status assessed · the year the Red List last looked
- 2019
- Population trend
- Decreasing
- Red List criteria
- B2ab(iii,iv,v)
The animal itself
- Limbs
- Four legs
- Venomous
- No
- Fangs
- None
- Longest recorded life
- 7.8years
- Body temperature when active · measured in the wild
- 26.4°C80 °F
- Body temp in the wild · mean, when active
- 25.6–26.4°C78–80 °F
Carey and Judge 2000: 6.9; Slavens and Slavens 1999: 7 and 10 months; Petzold 2008: 6+
mean body temperature of active individuals in nature
body temperature of active animals in nature
Size
- Length snout to vent · greatest recorded
- 220mm8.75 in
- Length snout to vent · adult female mean
- 178mm7 in
- Largest female · snout to vent
- 166.9mm6.5 in
- Hatchling length · snout to vent
- 60.3mm2.25 in
- Body mass · greatestcomputed
- 203.7g7.2 oz
- Body mass at hatchingmeasured
- 3.39g0.12 oz
Shai Meiri, unpublished
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
- Active
- Nocturnal
- Where it lives
- Semi-aquatic
- Habitat
- Forest, Wetlands
- Biome
- Tropical & Subtropical Moist Broadleaf Forests
- Region
- Oriental
- Mainland or island
- Found only on islands
- Elevation · above sea level
- 170–200m
- Range size
- 45,790km²
invertebrates and small vertebrates / fish and shrimps (Langner 2017), earthworms in captivity (Shirakawa and Bacchini 2015)
(e.g., Langner 2017, Jenssen and Sy 2022), strictly nocturnal (Leah et al. 2023)
fossorial, and semiaquatic / "all were active on the ground. Earless monitors were observed on land (Fig. 4) as well as submerged in water" (Langner 2017), semi aquatic (Shirakawa and Bacchini 2015), "subfossorial and semi-aquatic" (Leah et al. 2023)
178-197 (Langner 2017)
Breeding
- Reproduction
- Oviparous
- Average clutch
- 5.3eggs
- Eggs or young per clutch
- 1–8eggs
- Mean clutch
- 4.6–6eggs
- Clutches a year
- 1per year
e.g., Shirakawa and Bacchini 2015
6 (Shirakawa and Bacchini 2015, n=2), 1-8, mean 4.6 (Voronin and Kudryavtsev 2019, n=5),
Naming and history
- Suborder
- Sauria
- Infraorder
- Anguimoprha
- Subspecies
- No
- Described by
- Steindachner
- Moved to another genus · since it was first described
- No
- Described in
- 1878
- Type locality
- Malaysia
Keeping one
Borneo Earless Monitor is assessed as Endangered on the IUCN Red List. Species at risk in the wild are often covered by CITES and by national law, which decide what may be bought, sold, moved across a border or kept at all — and captive-bred and wild-caught animals are usually treated differently. Check the rules where you are before acquiring one. Nothing below is a judgement about keeping this species; it is what a published welfare standard says about space, and what the animal itself was measured doing.
2 ft 11 in × 2 ft 11 in × 21.5 in(88 × 88 × 55 cm)
Minimum length × width × height, for one animal. Bigger is always better.
The standard sizes ground-dwelling species at 4 × 4 × 2.5 times snout-vent length.
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 8.75 in (220 mm), at 4 × 4 × 2.5 times it, following the German federal welfare standard — how this is worked out.
Active animals measured in the wild averaged 80 °F (26.4 °C).
Mean body temperature of active individuals measured in nature. 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.
22kJ per day
Worked out for an animal of 204 g, the heaviest recorded for Borneo Earless 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 · snout to vent
- — Largest juvenile · shell length
- — Egg length
- — Egg width
- — Body mass · a typical adult
- — Body mass · adult female, mean
- — Preferred body temperature · chosen in a laboratory gradient
- — Eats arthropods
- — Eats vertebrates
- — Eats plant matter
- — How it hunts
- — 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
- — Colour on the back
- — Pattern on the back
- — Pupil
- — Sex decided by
- — Active season · shortest recorded
- — Active season · longest recorded
- — Density · lowest recorded
- — Density · highest recorded
- — Home range · largest recorded
- — Active in
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). Lanthanotus borneensis. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/lanthanotus-borneensis
@misc{lanthanotus_borneensis_2026,
title = {Lanthanotus borneensis},
author = {{The Reptile & Amphibian Encyclopedia}},
year = {2026},
url = {https://www.allanglescreatures.com/species/lanthanotus-borneensis}
}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.