Mediterranean Tree Frog (Hyla meridionalis)
Order Anura, Family Hylidae, Genus Hyla, Species H. meridionalis. This family consists of 'true tree frogs' characterized by rounded toe pads and an intercalary cartilage between phalanges.
Species
Mediterranean Tree Frog (Hyla meridionalis)
Family
Order Anura, Family Hylidae, Genus Hyla, Species H. meridionalis. This family consists of 'true tree frogs' characterized by rounded toe pads and an intercalary cartilage between phalanges.
Size
Adults typically measure between 4.5 and 6.5 cm in Snout-to-Vent Length (SVL). Females are generally larger than males. Weights usually range from 6 to 10 grams.
Conservation
IUCN Status: Least Concern. While widespread, populations are declining in some areas due to habitat loss, drainage of wetlands, pollution from pesticides, and the spread of chytrid fungus.
Description
Like a living emerald against the reeds, the Mediterranean Tree Frog is the quintessential arboreal amphibian of the Riviera and Iberian landscapes. Its glossy skin and acrobatic climbing skills make it a favorite for naturalists and gardeners alike.
Key Features
Bright green smooth skin; dark eye stripe ending at the shoulder; large circular toe pads; horizontal pupils; white or cream belly.
Physical Description
A relatively small, slender tree frog with a rounded snout and large, prominent eyes featuring horizontal pupils. It has long, slender limbs with well-developed adhesive toe pads and moderate webbing on the hind feet. The tympanum is distinct and clearly visible behind the eye.
Skin Texture & Coloration
The skin is very smooth on the back and slightly granular on the belly. Coloration is typically a bright, vivid apple-green, though it can change to brownish or grayish based on environment or mood. A distinctive dark lateral stripe starts at the nostril and passes through the eye, but crucially, in this species, it ends just behind the front leg attachment.
Distinguishing Features
The most diagnostic feature is the short lateral stripe that stops at the armpit, unlike the closely related Hyla arborea, whose stripe continues along the entire flank. It also lacks a dorsal 'step' in its stripe and generally appears more vibrant green.
Habitat
Occupies a variety of habitats including orchards, vineyards, gardens, and Mediterranean scrub near water. They are primarily arboreal, preferring reeds, bushes, and tall herbaceous vegetation near permanent or semi-permanent ponds and marshes.
Geographic Range
Native to Southwest Europe (Southern France, Monaco, Italy, Spain, Portugal) and Northwest Africa (Morocco, Algeria, Tunisia). It also exists on the Canary Islands and Madeira as an introduced species.
Behavior
Primarily nocturnal and crepuscular. They are exceptional climbers, often found sunning themselves on leaves high above the ground during spring mornings. When threatened, they rely on camouflage or high-speed leaps into water or dense foliage.
Diet & Feeding
An active insectivore that hunts by sit-and-wait ambush or short bursts of movement. Diet includes flies, mosquitoes, beetles, spiders, and occasionally small caterpillars. Its sticky, projectile tongue is highly efficient for catching aerial prey.
Reproduction
Breeding occurs from late winter to early summer. Males gather in choruses around water bodies. Amplexus is axillary. Females lay 800-1000 eggs in small clumps attached to submerged vegetation.
Vocalizations
The call is a deep, slow 'kraa-kraa-kraa' with long intervals between notes. It is significantly deeper and slower than the rapid, machine-gun-like call of Hyla arborea. The vocal sac is large and yellow when inflated.
Life Cycle
Eggs hatch into tadpoles within 8-15 days. The larval stage lasts about 3-4 months. Metamorphosis occurs in mid-summer. Juveniles are tiny (1.5 cm) but resemble adults. Maturity is reached in 2-3 years, with a lifespan of 5-8 years in the wild.
Conservation Status
IUCN Status: Least Concern. While widespread, populations are declining in some areas due to habitat loss, drainage of wetlands, pollution from pesticides, and the spread of chytrid fungus.
Toxicity & Defense
Not toxic to humans. Defenses include excellent disruptive camouflage and a mild skin mucus that can irritate mucous membranes (eyes/mouth) if handled and then touched. Its primary defense is its 'flash' leap and escape into water.
Ecological Role
Acts as a significant predator of insect pests, especially dipterans and small beetles. It serves as a vital prey source for snakes (like Natrix), birds (herons), and small carnivorous mammals.
Similar Species
European Tree Frog (Hyla arborea) - distinguished by the lateral stripe that continues all the way to the groin. Italian Tree Frog (Hyla intermedia) - very similar but geographically separated into the Italian peninsula.
Observation Tips
Listen for their deep clicking calls on warm spring evenings near standing water. Use a flashlight to scan reed stems; their eyes reflect light intensely. They are easiest to spot during the breeding season in March and April.
Handling & Safety
Minimize handling. Skin oils and salts on human hands can harm their permeable skin. If necessary, use wet hands and avoid using lotions or repellents. Wash hands thoroughly after contact to avoid irritation from their natural mucus.
Seasonal Activity
Active from February to October in the northern range; may be active year-round in warmer African or island populations. They undergo a brief period of dormancy (brumation) in winter, hiding in rock crevices or under root mats.
Cultural Significance
Commonly featured in Mediterranean folklore as a symbol of rain and fertility. It is frequently depicted in regional art and is a popular 'garden friend' in rural France and Spain.
Interesting Facts
The genus name 'Hyla' comes from Greek mythology, named after Hylas, a companion of Hercules. These frogs are remarkable weather predictors; their increased calling is often associated with rising humidity before rain.