All Angles Creatures
Squamata · LacertidaeEntry 534 of 21,572
Spanish Keeled Lizard, Algyroides hidalgoi

Reptilia · Squamata

Algyroides hidalgoiBosca, 1916

Spanish Keeled Lizard

Photograph by Gonzalo Colomer, CC BY, via iNaturalist

A ground-dwelling, day-active, meat-eating lizard from the Palearctic region, reaching 53 mm snout to vent.

Once published as Algyroides marchi — those names reach this page.

ReptiliaSquamataLacertidaeAlgyroides

Grows to
53mm
greatest recorded
Eats
Carnivorous
Active
Diurnal
Lives
Terrestrial
Body length across Lacertidae

Longer than only 11% of all species in Lacertidae anyone has measured.

11% of 372 species are smaller89% larger
35 mmthe whole family, smallest to largest444 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 35 to 444 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
Endangered
Status assessed · the year the Red List last looked
2008
Population trend
Decreasing
Red List criteria
B1ab(iii,iv)+2ab(iii,iv)

The animal itself

Limbs
Four legs
Venomous
No
Fangs
None
Preferred body temperature · chosen in a laboratory gradientmeasured
31.6°C

Size

Length snout to vent · greatest recorded
53mm2 in

max 53 mm SVL (Feldman et al. 2016)

Length snout to vent · adult female mean
47.7mm2 in
Largest female · snout to vent
47.7mm2 in

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

Hatchling length · snout to vent
23mm0.9 in
Largest juvenile · snout to vent
23mm0.9 in
Body mass · greatestcomputed
3.51g0.12 oz

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

Body mass at hatchingmeasured
0.33g0.01 oz

How it lives

Diet
Carnivorous

beatles (http://www.castillalamancha.es/medioambiente/SP/contenidos/fauna/default.asp?opcion=detalle&P=1&id=388), insects (Valverde 1958), Arthropods (Cardenete and Cardenete 2010)

Active
Diurnal
Where it lives
Terrestrial

Terrestrial and Leaf Litter (see Sources (general) column)

Habitat
Forest, Rocky, Wetlands
Biome
Mediterranean
Region
Palearctic
Mainland or island
Mainland
Elevation · above sea level
550–1700m

700-1700 (Speybroeck et al. 2016)

Range size
3547km²
Density
213per hectare

Breeding

Reproduction
Oviparous
Average clutch
2.5eggs
Eggs or young per clutch
1–5eggs

1-5 (Maso and Pijoan 2011), 2-3 (Speybroeck et al. 2016, Kwet 2015)

Mean clutch
2–3eggs
Clutches a year
1–3per year

Naming and history

Suborder
Sauria
Infraorder
Laterata
Subspecies
No
Described by
Bosca
Moved to another genus · since it was first described
No
Described in
1916
Type locality
Spain

Keeping one

Spanish Keeled Lizard 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.

8.25 in × 8.25 in × 5.25 in(21 × 21 × 13 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 2 in (53 mm), at 4 × 4 × 2.5 times it, following the German federal welfare standard — how this is worked out.

In a laboratory thermal gradient this species settled at 89 °F (31.6 °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.

1kJ per day

Worked out for an animal of 4 g, the heaviest recorded for Spanish Keeled 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
  • Longest recorded life
  • 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
  • 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
  • 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
  • Active season · shortest recorded
  • Active season · longest recorded
  • Home range · largest recorded
  • Active in

Others in Lacertidae

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). Algyroides hidalgoi. Retrieved 2026-09-08, from https://www.allanglescreatures.com/species/algyroides-hidalgoi

@misc{algyroides_hidalgoi_2026,
  title  = {Algyroides hidalgoi},
  author = {{The Reptile & Amphibian Encyclopedia}},
  year   = {2026},
  url    = {https://www.allanglescreatures.com/species/algyroides-hidalgoi}
}

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.