Pebble toad
| Pebble toad | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
European toad ( Oreophrynella nigra ) |
||||||||||||
| Systematics | ||||||||||||
|
||||||||||||
| Scientific name | ||||||||||||
| Oreophrynella nigra | ||||||||||||
| Señaris , Ayarzaguena & Gorzula , 1994 |
The European toad ( Oreophrynella nigra ) is a South American species of toad of the genus Oreophrynella . The specific epithet nigra , Latin for black, refers to the color.
features
The males of the European toad reach a head-trunk length of 16.5 to 23.5 mm, the females 20.4 to 30.0 mm. It is black on the upper side (dorsal) and underneath (ventral) and without drawing. Conserved , the color is uniformly dark brown or black with a slightly lighter belly side. The skin is soft, sometimes wrinkled and tuberculated . Their head is slightly wider than it is long, the muzzle is flattened in profile, the edge of the muzzle is short and steep. The area between the nostrils is concave (curved inward). Arms and legs are thin, the hands are flat webbed and covered with tubercles. The fingertips are enlarged. The toes are short and flat with three toes connected at the base. The tympanum , the membrane of the hearing organ, is not visible, there are no teeth. The tongue is oval and attached to the front.
distribution
The pebble toad is endemic to the Guiana Highlands in Venezuela . So far it has only been found in the state of Bolívar on the Tepuis Kukenán and Yuruaní and lives there at an altitude of 2300 to 2700 meters above sea level .
Habitat and way of life
The pebble toad is a diurnal rock inhabitant. It lives in open terrain on bare limestone on the edge of patches of vegetation with bushes, flowering plants and bromeliads and feeds on insects such as mites , ants and beetles . For its part, the toad is one of the prey of tarantulas , from which it protects itself through its color and the escape behavior described below.
The reproductive behavior is not yet fully understood. Depending on the observation, group clutches with 8 to 35 eggs or single clutches under moss and stones with groups of 8 to 13 eggs are formed. In any case, the eggs are about 5 to 6 mm in diameter and there is a direct development without the tadpole stage with a staggered development time.
particularities
The name pebble toad ( Engl . Pebble Toad ) is derived from their flight behavior in imminent danger from. It can curl up almost spherically and, if it is on an elevated, mostly stony level, drop like a pebble into the depths and thus escape its opponents.
In the BBC documentary Our Life (2011; English: One Life ), the flight behavior of the European toad was briefly discussed.
Danger
The distribution of the common toad is limited to only two localities. Even if there is no current threat, fires, for example, can threaten the population. The International Union for Conservation of Nature and Natural Resources (IUCN) therefore classifies the toad as vulnerable (Vulnerable, VU), despite the stable population development.
Individual evidence
- ↑ a b c Amphibia Web: Oreophrynella nigra
- ↑ a b Oreophrynella nigra in the IUCN Red List of Threatened Species . Posted by: Enrique La Marca, Celsa Señaris, 2004. Retrieved March 11, 2012.
- ↑ Matt Walker: Pebble toad's rock and roll life . BBC Earth News, October 15, 2009. Retrieved November 5, 2013.
- ↑ BBC documentary: Our life - Kieselkröte , accessed on March 11, 2012
literature
- Josefa Celsa Señaris, José Ayarzaguena, Stefan Gorzula: Los sapos de la familia Bufonidae (Amphibia, Anura) de las tierras altas de la Guayana venezolana. Publicaciones de la Asociación de Amigos de Doñana, 3, 1994 (first description)
Web links
- Oreophrynella nigra in the endangered Red List species the IUCN 2013. Posted by: Enrique La Marca, Celsa Señaris, 2004. Retrieved on November 5, 2013.
- Venezuela pebble toad ( Oreophrynella nigra ) at Arkive (video of a pebble toad rolling off the mountain). Retrieved November 5, 2013.