All Angles Creatures
Squamata · XantusiidaeEntry 21,299 of 21,572

Reptilia · Squamata

Xantusia arizonaeKlauber, 1931

Arizona Night Lizard

No photograph of this species exists under a license anyone may reuse. It gets the same page regardless.

A rock-dwelling, active by day or night, meat-eating lizard from the Nearctic region, reaching 60 mm snout to vent.

ReptiliaSquamataXantusiidaeXantusia

Grows to
60mm
greatest recorded
Eats
Carnivorous
Active
Cathemeral
Lives up to
10years
Body length across Xantusiidae

Longer than only 39% of all species in Xantusiidae anyone has measured.

39% of 36 species are smaller61% larger
36 mmthe whole family, smallest to largest153 mm

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 36 to 153 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

37 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
2007
Population trend
Stable

The animal itself

Limbs
Four legs
Venomous
No
Fangs
None
Longest recorded life
10years

over 10 years (Jones and Lovich 2009)

Body temperature when active · measured in the wild
25.3°C78 °F

mean body temperature of active individuals in nature

Body temp in the wild · mean, when active
25.3°C

body temperature of active animals in nature

Size

Length snout to vent · greatest recorded
60mm2.25 in

max 60 mm SVL (Feldman et al. 2016)

Length snout to vent · adult female mean
53mm2 in
Largest female · snout to vent
53mm2 in

snout-vent length; the source column mixes this with straight carapace length

Hatchling length · snout to vent
26mm1 in
Largest juvenile · snout to vent
26mm1 in
Body mass · greatestcomputed
4.21g0.15 oz

computed from length by a family-level allometric equation, not weighed

How it lives

Diet
Carnivorous

arthropods (Brattstrom 1952, Jones and Lovich 2009, Stebbins and McGinnis 2018)

Active
Cathemeral

Cathemeral: Diurnal and Crepuscular, nocturnal on hot summers (Stebbings 2003)

Where it lives
Saxicolous

e.g., Stebbins and McGinnis 2018

Habitat
Rocky
Biome
Deserts & Xeric Shrublands
Region
Nearctic
Mainland or island
Mainland
Elevation · above sea level
1000–1590m
Range size
784km²

Breeding

Reproduction
Viviparous
Average clutch
1.69eggs
Eggs or young per clutch
1–2eggs

1-2, mean 1.8 (Goldberg and Bezy 2014, Bezy and Goldberg 2015)

Mean clutch
1.57–1.8eggs
Clutches a year
1per year

Naming and history

Suborder
Sauria
Infraorder
Scincoidea
Subspecies
No
Described by
Klauber
Moved to another genus · since it was first described
No
Described in
1931
Type locality
USA

Keeping one

9.5 in × 9.5 in × 6 in(24 × 24 × 15 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.

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 2.25 in (60 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 78 °F (25.3 °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.

1kJ per day

Worked out for an animal of 4 g, the heaviest recorded for Arizona Night Lizard — 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
  • Body mass at hatching
  • 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
  • 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 Xantusiidae

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). Xantusia arizonae. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/xantusia-arizonae

@misc{xantusia_arizonae_2026,
  title  = {Xantusia arizonae},
  author = {{The Reptile & Amphibian Encyclopedia}},
  year   = {2026},
  url    = {https://www.allanglescreatures.com/species/xantusia-arizonae}
}

Sources

  1. Meiri, S. (2024). SquamBase — a database of squamate (Reptilia: Squamata) traits. Global Ecology and Biogeography. Public domain (CC0).
  2. Oskyrko, O. et al. (2024). ReptTraits: a comprehensive dataset of ecological traits in reptiles. Scientific Data. Used under CC BY 4.0.
  3. Catalogue of Life (dataset 3LR), used under CC BY.