OPHISAURUS (GLASS LIZARD)

Contents hide

1) Introduction

2) Classification of Ophisaurus (Glass Lizard)

3) Geographical distribution

4) Habit and habitat

5) General Characteristics of Ophisaurus (Glass Lizard)

6) Ecological Importance

7) Conservation Status

8) Special features

9) Identification

Introduction

Ophisaurus, commonly referred to as glass lizards, are a genus of legless lizards found across North America, Europe, and parts of Asia. Despite their snake-like appearance, they are true lizards, distinguished by features like movable eyelids and external ear openings. Their name “glass lizard” comes from their ability to shed their tails, which break into pieces like glass when threatened.

Classification of Ophisaurus (Glass Lizard)

Phylum :- Chordata (Dorsal tubular nerve cord, notochord and gill-slits present.)
Group :- Craniata (Definite head, Cranium with brain present.)
Sub phylum :- Vertebrata (Vertebral column present.)
Division :- Gnathostomata (Jaws and paired appendages present.)
Super Class :- Tetrapoda (Paired limbs, lungs, cornified skin and bony skeleton.)
Class :- Reptilia (Scaly vertebrates. Right and left aortic arches present. Single condyle. Pulmonary respiration. Embryo with amnion and allantois.)
Sub Class :- Diapsida (Skull with two temporal openings separated by post-orbital and squamosal.)
Order :- Squamata (Lizards and snakes with horny epidermal scales or shields. Quadrate bone movable. Vertebrae procoelous. Anal opening transverse.. Vertebrae amphicentrous.)
Sub-order :- Iguania (Lizards. Body slender, limbs 4. Pterygoid in contact with quadrate. Eyelids movable.)
Family :- Anguidae (Limbs absent. Body selender.)
Genus :- Ophiosaurus

Geographical distribution

Ophisaurus is commonly found in U.S.A., Mexico, Africa, Western Asia and India. The Indian species is O. gracilis found in the Eastern Himalayas.

Habit and habitat

It is a burrowing animal.

General Characteristics of Ophisaurus (Glass Lizard)

Commonly called as glass snake.
Body is short, snake-like, having greenish brown colouration with longitudinal stripes and divided into head, trunk and tail.
Head contains mouth, nostrils and eyes. The eyes with eyelids are reduced due to burrowing life. Behind eyes are tympanum.
Rest of the body is covered with rectangular epidermal scales arranged in circular and longitudinal rows. Beneath scales, the body plates have hard texture.
Ventrolateral longitudinal skin folds terminate into two locomotory spikes near cloaca.
Limbs are absent. Tail is fragile and breaks more quickly than in any other lizard.

Ecological Importance

Predation Control:
- Glass lizards are insectivores and small carnivores, feeding on insects, spiders, small mammals, and reptiles.
- They help regulate populations of agricultural pests and other small animals, maintaining ecological balance.
Prey for Larger Predators: They serve as prey for birds, mammals, and larger reptiles, supporting food web dynamics.
Habitat Maintenance: By burrowing and foraging in soil, they contribute to soil aeration and nutrient cycling in their habitats.

Conservation Status

Status of Species: Conservation statuses vary by species:
- Ophisaurus attenuatus (Slender Glass Lizard): Least Concern.
- Ophisaurus compressus (Island Glass Lizard): Data Deficient.
- Ophisaurus ventralis (Eastern Glass Lizard): Least Concern, though habitat loss poses threats.
Threats:
- Habitat destruction due to urbanization and agricultural expansion.
- Road mortality, as they are mistaken for snakes.
- Predation by domestic animals and invasive species.
Conservation Efforts:
- Protection of natural habitats and reduction of deforestation.
- Educational campaigns to reduce human-induced threats, such as roadkill and persecution.
- Research and monitoring to gather more data on less-studied species.

Special features

Ophisaurus is distinguished from snakes by a narrow gape of mouth, movable eyelids and tympanic holes and from limbless Amphibia by the presence of epidermal scales and a long tail.
A group of American limbless lizards (worm lizards) have head shields, annular bands like earthworms and no scales.
Legless but Not Snakes: Unlike snakes, glass lizards have movable eyelids, external ear openings, and inflexible jaws.
Tail Autotomy:
- They can shed their tails when threatened, which continues to wriggle and distract predators.
- The tail regrows, but it is shorter and less vibrant.
Burrowing Adaptation: Their streamlined bodies allow them to burrow efficiently in sandy or loose soil.
Diurnal Behavior: Most glass lizards are active during the day, relying on keen vision to hunt prey.
Longevity and Resilience: They are known for their relatively long lifespans and ability to survive in a variety of habitats, from grasslands to forests.