Psammophilus dorsalis
The Peninsular rock agama, also known as the South Indian rock agama (Psammophilus dorsalis), is a common lizard species inhabiting the rocky hills of south India. Adult males in the breeding season display striking bright colors, transforming their upper parts to vermilion red or yellow, while females and young are typically olive-brown with dark markings. These lizards are insectivores and are known for their habit of basking on exposed rocks, where their coloration provides camouflage.
Key Facts
- ›Found on rocky hills in south India.
- ›Males develop bright red or yellow coloration during the breeding season.
- ›Feeds primarily on insects.
- ›Adult males have enlarged scales at the base of their tails.
- ›Known for basking on exposed rocks.
- ›Females and juveniles have a more cryptic olive-brown coloration.
Peninsular Rock Agama, South Indian Rock Agama
South India
Rocky Hills, Exposed Rocks
- Large, Elongated, and Depressed Head With Swollen Cheeks In Adult Males.
- Snout Is Longer Than the Eye Cavity Diameter.
- Upper Head Scales Are Unequal and Smooth Or Obtusely Keeled.
- Clear and Sharp Edge On the Canthus Rostralis and Supraciliary.
- Two Small, Separated Spines Or Groups of Spines Above the Ear May Be Present Or Absent.
- Tympanum Diameter Is Half Or A Little More Than Half That of the Orbit.
- 10 To 13 Upper and Lower Labial Scales.
- Slightly Flattened Body.
- Dorsal Scales Are Small, Uniform, Smooth, Or Feebly Keeled In Adults, Strongly Keeled In the Young.
- Dorsal Crest Is Reduced To A Ridge of Enlarged Scales.
- Ventral Scales Are As Large As Dorsals and Smooth .
- 115 To 150 Scales Around the Middle of the Body.
- Gular Scales Are Smaller Than Ventral Scales.
- Four Or Five Enlarged Scales On the Chin Parallel With the Anterior Labials.
- Strong Transverse Fold Covered With Small Scales Across the Throat.
- Nuchal and Dorsal Crests Are Tooth-Like Protrusions.
- Strong Legs Covered With Uniform, Keeled Scales.
- Hind Limb Extends To the Ear Or Rear End of the Eye When Extended Forward.
- Tail Is Slightly Flattened and Covered With Keeled Scales.
- Adult Male Tail Is Distinctly Swollen At the Base With Thickened Scales.
- Young and Females Are Olive-Brown, Spotted, Speckled, Or Marbled With Dark Brown, With A Series of White Spots Along Each Side of the Back.
- Adult Male Has Pale Brownish Color On the Head and Back, Yellowish-Brown Lips Extending As A Strip Beyond the Ear.
- Adult Male Has A Dark Brown Or Black Lateral Stripe Behind the Eye.
- Adult Male Has A Yellow Underside With the Throat Mottled With Grey.
- Breeding Season Male Has Fine Vermilion Red Or Yellow Upper Parts, Sometimes Pink Lip Stripe, and Black Undersides, Limbs, and Tail.
Insects
Bask On Bare Rocks., Flatten Bodies When Birds Fly Overhead., Males Bask Openly On Exposed Rocks., Show Head Push-Up Displays .
Birds
About Psammophilus dorsalis
The Peninsular rock agama, scientifically known as Psammophilus dorsalis, is a common lizard species native to the rocky hills of south India. It is also referred to as the South Indian rock agama.
Description and Appearance
This species is characterized by a large, elongated, and depressed head, with adult males exhibiting swollen cheeks. The snout is notably longer than the diameter of the eye socket. The scales on the upper head are generally smooth or obtusely keeled, becoming larger on the brow than on the occiput. A distinct edge runs along the canthus rostralis and supraciliary ridges, and small spines may be present above the ear. The body is slightly flattened, with small, uniform dorsal scales that are smooth or feebly keeled in adults but strongly keeled in juveniles. A dorsal crest is present as a ridge of enlarged scales, and ventral scales are similar in size to dorsal scales and are smooth. The legs are robust and covered in uniform, keeled scales. When extended forward, the hind limb of an adult specimen typically reaches the ear or the rear of the eye. The tail is somewhat flattened and adorned with keeled scales, which are larger on the underside. In adult males, the base of the tail is distinctly swollen with thickened scales.
The coloration of Psammophilus dorsalis varies significantly between sexes and ages. Young and female lizards are typically olive-brown, marked with spots, speckles, or marbling of dark brown. They often display a series of elongated white spots along each side of their back. Adult males, especially during the breeding season, undergo a dramatic transformation. Their upper parts can become a striking vermilion red or yellow, with lips that are yellowish-brown and may extend as a strip beyond the ear. A prominent dark brown or black lateral stripe begins behind the eye and widens along the lower sides. The underside of the male is yellow, with the throat often mottled in grey. During the breeding season, the undersides, limbs, and tail of the male become black.
Habitat and Behavior
Psammophilus dorsalis is predominantly found in hilly regions of southern India, generally south of approximately 16°N latitude. They inhabit areas such as the Western Ghats, Nilgiris, South Arcot, and Nallamalai Hills, with sightings reported at altitudes up to 6000 feet above sea level in the Nilgiris. They are particularly common in certain parts of the Nilgiris and were noted as being very common near Bangalore.
These lizards are well-adapted to their environment and are often seen basking on bare rocks, where their cryptic coloration provides effective camouflage. Their diet consists primarily of insects. Males are known to bask openly on exposed rocks and engage in distinctive head-pushing displays. When birds fly overhead, they exhibit a defensive behavior by flattening their bodies.
Size
In terms of size, Psammophilus dorsalis can reach a snout-to-vent length of approximately 135 mm (5.3 inches), with a tail that measures around 200 mm (7.9 inches). Females are generally smaller than males.
Source: Wikipedia ↗
Frequently Asked Questions
What is the common name for Psammophilus dorsalis?
Psammophilus dorsalis is commonly known as the Peninsular rock agama or the South Indian rock agama. These names reflect its geographic distribution and preferred habitat.
What does the Peninsular rock agama eat?
The Peninsular rock agama is an insectivore, meaning its diet consists mainly of insects. This provides them with essential nutrients for survival and energy.
How can I distinguish between male and female Peninsular rock agamas?
During the breeding season, adult males develop vibrant colors, with their upper parts turning vermilion red or yellow, and their undersides and limbs becoming black. Females and young lizards are typically olive-brown with dark brown markings, offering better camouflage.
Where does the Peninsular rock agama live?
This species is found on rocky hills in southern India, generally south of 16°N latitude. They inhabit hilly regions, including areas like the Western Ghats and Nilgiris, at elevations up to 6000 feet.
What is the typical size of a Peninsular rock agama?
Adult lizards can reach a snout-to-vent length of approximately 135 mm, with a tail that can be up to 200 mm long. Females are generally smaller than males.
How do Peninsular rock agamas behave?
Males are often seen basking openly on exposed rocks and engage in head-pushing displays. They can flatten their bodies when birds fly overhead, likely as a defensive response to potential predators.
Related Lizards
Peninsular rock agama
The Peninsular rock agama is a common lizard species found on rocky hills in southern India. Adult males are distinguished by swollen cheeks and can display brilliant coloration during the breeding season, while females and young are typically olive-brown with dark markings. These lizards are insectivorous and exhibit behaviors like head-pushing displays and flattening their bodies to avoid predators.
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