Hemidactylus turcicus (Linnaeus, 1758)

Common Name and Size

Hemidactylus turcicus, commonly called the Mediterranean gecko, is a very small lizard that generally reaches 10–13 cm (4–5 inches) in total length.

Head and Sensory Features

It has sticky toe pads, vertical pupils, and large eyes that lack eyelids.

Snout Characteristics

Its snout is rounded, and it is approximately as long as the distance between the eye and ear opening, measuring 1.25 to 1.3 times the diameter of the eye socket (orbit).

Forehead and Ear Features

The forehead is slightly concave, and the ear opening is oval, oblique, and nearly half the diameter of the eye.

Body and Limb Proportions

The body and limbs are moderately sized.

Digit Structure

Digit length varies across the foot, but the inner digit is always well developed.

Subdigital Lamellae Count

There are 6 to 8 lamellae under the inner digits, 8 to 10 under the fourth finger, and 9 to 11 under the fourth toe.

Head Scale Texture

The front of the head is covered in large granules, while the back of the head has minute granules mixed with round tubercles.

Rostral Scale Features

The rostral scale is four-sided, less than twice as broad as it is deep, with a medial cleft above it.

Nostril Placement

The nostril is located between the rostral scale, the first upper labial scale, and three nasal scales.

Labial Scale Count

This species has 7 to 10 upper labial scales and 6 to 8 lower labial scales.

Mental and Chin Shield Features

The mental scale is large and triangular, at least twice as long as the adjacent labial scales, with its pointed end positioned between two large chin-shields that may make contact behind it; a smaller chin shield sits on each side of this larger pair.

Dorsal Body Granules and Tubercles

The upper surface of the body is covered in minute granules mixed with large tubercles.

Dorsal Tubercle Arrangement

These tubercles are generally larger than the gaps between them, are suboval and trihedral in shape, and arranged in 14 or 16 fairly regular longitudinal rows.

Abdominal Scale Features

Abdominal scales are small, smooth, roundish-hexagonal, and overlapping (imbricate).

Male Preanal Pores

Males have a short angular series of 4 to 10 preanal pores, with 2 being an exceptional count.

Tail Shape and Scaling

The tail is cylindrical, slightly flattened, and tapering.

Tail Surface Scaling

Its upper surface is covered in minute scales and transverse rows of large, keeled tubercles, while its lower surface has a row of large, transversely expanded plates.

Coloration

The upper body is light brown or grayish with darker spots; many tubercles and all lower body surfaces are white.

Color Variation

Individuals may be completely translucent aside from their spotting, and some individuals have darker overall coloration.

Escape Behavior

When fleeing, Mediterranean geckos often move toward dark areas.

Social Structure

They can be found alone, or in groups of five or more individuals.

Native Range and Invasion Status

This species is native to the Mediterranean region, and is one of the most widely successful gecko species in the world.

Conservation Status

It has spread across much of the globe and established stable populations far outside its native range, and it is not classified as threatened or endangered.

Global Distribution

It occurs in countries with Mediterranean climates including Portugal, Spain, France, Italy, Greece, Israel, Malta, southern Bulgaria, North Macedonia, coastal Croatia (except western Istria), Bosnia and Herzegovina, the Adriatic islands, coastal Montenegro, coastal Albania, Cyprus, Turkey, northern Morocco, Algeria, Tunisia, Jordan, Syria, Libya, Egypt, Lebanon, northern Yemen (the Socotra Archipelago), Somalia, Eritrea, Kenya, southern Iran, Iraq, Oman, Qatar, Saudi Arabia, Pakistan, India, the Balearic Islands (Island Addaya Grande), the introduced Canary Islands populations of Gran Canaria and Tenerife, Panama, Puerto Rico, Belize, and Cuba.

1974 United States Distribution

As of 1974, it was recorded from scattered locations in the Southwestern United States (Arizona, California, Nevada, and New Mexico) and across a larger area of the Southern United States (Alabama, Arkansas, Florida, Georgia, Kansas, Kentucky, Louisiana, Maryland, Mississippi, Missouri, North Carolina, Oklahoma, South Carolina, Texas, and Virginia), with particularly well-established populations in eastern Gulf Coast states.

Recent Eastern US Records

More recently, published records document this species in several localities in Pennsylvania and Tennessee.

Indiana Occurrence Record

It was also reported from Indiana in 2019, though it was not known at that time whether the individual belonged to an established local population.

Introduced Mexican Distribution

In Mexico, introduced populations are known from the states of Tamaulipas, Veracruz, Tabasco, Campeche, Yucatán, Baja California, Chihuahua, Coahuila, Sonora, Durango, and Nuevo León.

Anthropogenic Habitat Use

Mediterranean house geckos occupy a wide range of habitats, most commonly in areas near human activity including university campuses, cemeteries, coastal regions, and shrublands.

Urban Microhabitat

In these urban or suburban areas, they are typically found in the cracks of old brick buildings.

Urban Habitat Adaptation Benefit

These urban habitats are less structurally complex than more natural settings, which supports the species' widespread success across its introduced range.

Natural Habitat Use

They can also occur in more natural areas including mountain cliffs and caves.

Nest Site Locations

Their nests are found in trash piles, attics, or under building baseboards.

Sexual Maturity Timeline

Mediterranean house geckos reach sexual maturity between four months and one year after hatching.

Mating Vocalizations

Males produce clicking sounds to attract mates, and females respond with their own squeaks.

Copulatory Behavior

This species practices copulatory biting, and stronger bites are associated with higher fertilization success.

Fertilization Method

Fertilization is internal.

Breeding Season and Clutch Traits

The breeding season typically runs from April to August each year, and eggs are laid between mid-May and August in an average clutch size of two.

Sperm Storage Adaptation

Females can experience delayed fertilization, as they can store sperm in a funnel-shaped organ called the infundibulum for up to five months.

Gestation Period

Because of this, the exact gestation length is unknown, but it is estimated to be around 40–60 days.

Parental Care Behavior

No parental care from either males or females has been observed; in fact, males have been recorded biting juvenile geckos.