Rana temporaria
SUBFAMILY
Raninae, tribe Ranini
TAXONOMY
Rana temporaria Linnaeus, 1758, Sweden.
OTHER COMMON NAMES
English: European common frog, grass frog; French: Grenouille rousse; German: Grasfrosch; Spanish: Rana roja, rana bermeja.
PHYSICAL CHARACTERISTICS
This is the most common European species of the group of brown frogs, the distribution of which covers most of Europe from sea level in the north to above 6,562 ft (2,000 m) in the south. Over this vast area, the species shows considerable variety in most characters, and several subspecies have been recognized. It is 2.4–3.7 in (60–95 mm) in snout-vent length and displays a vast array of colorations, including brown, reddish, orange, yellow, olive, gray, and blackish; none is green. The dorsum is more or less spotted, the legs are barred, and the eye coloration varies considerably, with a basic golden iris, which may be more or less charged in melanophores. The hind limbs are short but may be longer in some southern populations or regions. The webbing is usually large but is less developed in Iberian populations. Males have nuptial pads and internal vocal sacs, and their throats are bluish during the breeding period.
DISTRIBUTION
The species is distributed throughout Europe.
HABITAT
This frog occurs in forest habitats and grasslands. At high elevations and latitudes, it lives in meadows, marshes, and peat bogs.
BEHAVIOR
This frog spends most of its life on the forest floor or in the grass, but it moves to ponds for breeding. In mountain habitats it may remain around ponds or lakes for most of the year.
FEEDING ECOLOGY AND DIET
Little is known.
REPRODUCTIVE BIOLOGY
This species breeds as soon as snow and ice melt, at widely different periods according to elevation and latitude. Males gather for calling, and egg masses often are grouped by the dozens or hundreds in shallow parts of the ponds. Each female lays 1,000–4,000 eggs that are each 0.08–0.12 in (2–3 mm) in diameter. Tadpoles, which have 3–4/4 tooth rows, may reach a length of 1.77 in (45 mm) before metamorphosis.
CONSERVATION STATUS
This species is not listed by the IUCN. However, in several countries, and especially in mountain areas, commercial exploitation of these frogs for human consumption has had drastic negative impacts on the populations.
SIGNIFICANCE TO HUMANS
This species is eaten by Europeans.
