Asian brown frog
| Asian brown frog | ||||||||||||
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Asian brown frog ( Rana macrocnemis ) |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Rana macrocnemis | ||||||||||||
| Boulenger , 1885 |
The small Asian brown frog ( Rana macrocnemis ) is within the order of Anura to the family of Real frogs as well as to the kind of genuine frogs . In addition, it is counted according to appearance, way of life and relationships to the group of brown frogs . Its distribution area extends from the Caucasus to Turkey and Iran .
features
It is a long-legged brown frog with a rounded or moderately pointed snout. The skin is relatively smooth. The top is olive green, greyish, dark purple, orange-pink, reddish or brown in color. A drawing made up of dark spots can vary in its arrangement, size and number of spots. A light longitudinal line may be indicated on the middle of the back or it may be missing. The ventral side is usually unmarked and colored pink to orange-red, sometimes whitish or yellowish. The throat is white or gray in color and is occasionally spotted. This drawing extends to the chest in some copies. The males have oestrus calluses on their first finger at spawning time and have internal vocal sacs .
distribution and habitat
The distribution area of the Asian brown frog extends from the Caucasus through Anatolia to Iran. An isolated population can be found in the Stavropolskii region in the Strizhament Mountains in the European part of Russia , another in the area of Karagöl and Çiniligöl in Bolkar Dagi (Turkey). These are considered relics of an originally wider distribution of the species. The presence in Iraq is also assumed, but has not yet been confirmed. The greatest abundance can be observed in the Caucasus.
The altitude distribution ranges from 1000 to 2300 meters. The species occurs in herbaceous deciduous and mixed forests, swamp areas, steppes, subalpine and alpine regions. In dry areas, the adult animals always live near permanent bodies of water such as lakes, ponds, rivers, ditches and river pools. The spawning grounds can be located in calm water areas of flowing waters as well as in still waters.
Reproduction and Individual Development
Hibernation takes place aquatic or terrestrial depending on the habitat conditions and begins, depending on the altitude, from the end of September to the beginning of November and ends between February and May. Then the sexually mature frogs migrate to the spawning water, where they mate on the way (axillary amplexus ) or directly at the spawning site. The main spawning phase is around April / May. A female produces a single ball of spawn with 580 to 3500 eggs. The tadpoles reach metamorphosis between the end of May and the beginning of October, depending on the altitude and water temperatures , but this is usually the case in June / July. In cold, deep waters, the larvae may occasionally overwinter. The frogs reach sexual maturity in the second or third year of life.
Systematics
The taxonomic status of the brown frogs of the Caucasus, Asia Minor and neighboring regions is controversial. Another species, Rana camerani , is sometimes distinguished because of major morphological differences. This variability can also be interpreted intraspecific, especially since both forms are neither geographically isolated nor separated in their reproduction. A previously differentiated species Rana holtzi is now also included by some authors Rana macrocnemis . Both forms are sometimes seen as subspecies. As a result, there are three subspecies - R. macrocnemis macrocnemis , R. macrocnemis camerani and R. macrocnemis holtzi - while other earlier subspecies are now regarded as separate species Rana tavasensis and Rana pseudodalmatina .
Danger
The Asian brown frog is classified as Least Concern in the IUCN's Red List of Threatened Species because it has a relatively large distribution area, is more adaptable to habitat changes and is believed to have a relatively large total population. The main threat to this species comes from habitat loss, which occurs as a result of increasing habitat change through agriculture and settlement.
supporting documents
- ↑ a b c d Artportrait at Amphibiaweb.org accessed on August 1, 2008
- ↑ Database "Amphibian Species of the World" ( Memento of the original dated November 2, 2005 in the Internet Archive ) Info: The archive link was inserted automatically and not yet checked. Please check the original and archive link according to the instructions and then remove this notice.
- ↑ Rana macrocnemis in the endangered Red List species the IUCN 2008. Posted by: Kuzmin, S., Tarkhnishvili, D., Ishchenko, V., Ananjeva, N. Orlov, N., Tuniyev, B., Sparreboom, M. , Ugurtas, I., Rastegar-Pouyani, N., Papenfuss, T. & Anderson, S., 2008. Retrieved August 1, 2008.
Web links
- IUCN Red List: Rana macrocnemis (Engl .; with distribution map )
- Species portrait at Amphibiaweb.org (Engl.)
- Photo of Rana macrocnemis macrocnemis from Georgia (at www.herpetofauna.at)
- Photos of Rana macrocnemis camerani from Georgia (at www.herpetofauna.at) (three pictures, click through )