Squamata Families - Lizards

Dibamidae

blind skinks

Dibamidae distribution

SE Asia, Indonesia, Philippines, Mexico

Dibamidae characteristics

sister to all other squamates, longest independent evolutionary history from other clades, small, oviparous, adapted for burrowing (vestigial eyes covered by scales, no external ear openings), presence of hindlimbs are sexually dimorphic

Pygopodidae

flap-footed lizards

Pyogopodidae distribution

Australia, New Guinea

Pygopodidae characteristics

oviparous, adapted for burrowing (eyes covered by scale), hindlimbs are little flaps, no forelimbs, can hear higher pitched sounds than other reptiles, “squeak”

Gekkonidae

Spectacled Geckos

Gekkonidae distribution

worldwide (except colder areas of Americas and Asia)

Gekkonidae characteristics

2nd largest lizard family, most have toepads, some parthenogenesis, 1/10 species communally nest, popular in pet trade, some invasive

Scincidae

skinks

Scincidae distribution

worldwide (except colder parts of Europe/Asia)

Scincidae characteristics

largest family of lizard, highly variable, frequent limb reduction, oviparous and viviparous, shiny cycloid scales, osteoderms comprised of multiple bones

Cordylidae

Girdled Lizards

Cordylidae distribution

Southern Africa

Cordylidae characteristics

heavily armored (osteoderms, spines), transverse circle of scales (“girdles”), inflate to wedge between rocks, some use tail as weapon, some roll into ball with tail in mouth, flat lizards, colorful, complex social structure, all but one genus is viviparous

Teiidae

Whiptails, Tegus, and Relatives

Teiidae distribution

North and South America

Teiidae characteristics

active, diurnal, oviparous, medium to large, some parthenogenesis, major component of SW US lizard fauna

Lacertidae

Wall Lizards and relatives

Lacertidae distribution

Africa, Asia, Europe

Lacertidae characteristics

active and diurnal, sister taxa to worm lizards, oviparous (except one species), small to medium, well-developed limbs, small granular scales

Bipedidae

Mole-limbed Worm Lizards

Bipedidae distribution

Mexico (Baja and SW mainland), arid scrub and desert

Bipedidae characteristics

oviparous, autonomous tail plugs burrow, only worm lizard with limbs, toes are all thumbs, rebuilt limbs from limbless ancestor

Amphisbaenidae

worm lizards

Amphisbaenidae distribution

Sub-Saharan Africa, South America

Amphisbaenidae characteristics

largest/most widespread worm lizard, big, oviparous and viviparous, variety of head shapes

Helodermatidae

Gila Monster and Beaded Lizard

Helodermatidae distribution

Sonoran Desert down Pacific Coast of Mexico to Guatemala

Helodermatidae characteristics

big and chunky, short tail for fat storage, venomous glands in bottom jaw, oviparous, vertebrate diet, active foraging, periodically active, nestlings

Anguidae

Slowworms, glass lizards, alligator lizards….

Anguidae distribution

North America, Europe, Middle East, parts of China and Indonesia

Anguidae characteristics

diurnal, insectivores, viviparous and oviparous, egg-guarding, elongation and limb reduction, readily drops tails

Varanidae

Monitors and Goannas

Varanidae distribution

Africa, South Asia, Indonesia, Philippines, New Guinea, Australia

Varanidae characteristics

Fast active pursuit predators, throat muscles pump air into lungs, larger/complex lungs, male-male combat, some species potentially venomous, morphologically includes Mososaurs

Chamaeleonidae

Chameleons

Chamaeleonidae distribution

Africa, Madagascar, India, Mediterranean shores

Chamaeleonidae characteristics

laterally compressed bodies, zygodactylous feet, eyes move independently, fast projectile tongues, diurnal insectivores (2 species eat birds), casques/horns/crests, prehensile tails, includes smallest vertebrate in the world

Phrynosomatidae

Spiny and sand lizards

Phrynosomatidae distribution

North America

Phrynosomatidae characteristics

diverse morphology and ecology, oviparous and viviparous, desert/dry land adapted species, includes horned toad

Iguanidae

Iguanas

Iguanidae distribution

Southern North America, Northern South America, Caribbean, Galapagos, Fiji/Tonga

Iguanidae characteristics

large, largely herbivorous as adults, variety of habitats, some have special colon partitions with increased surface area to digest plants

Dactyloidae

Anoles

Dactyloidae distribution

SE USA, Mexico, Caribbean, South America

Dactyloidae characteristics

diverse, largely arboreal, toe pads (can’t climb glass), brightly colored dewlaps, model system for studying adaptive radiation, deposit 1-2 eggs weekly during breeding season

Crotaphytidae

collared and leopard lizards

Crotaphytidae distribution

West, Midwest, and Southwest USA

Crotaphytidae characteristics

medium sized, mesic and arid areas, colorful, big heads with strong bite, male-male combat determined by bite strength, insectivores, some eat vertebrates and other lizards