Rana saharica is a large frog, with one female from Morocco reported to measure 104.5 mm SVL (Schleich et al. 1996).
The published description for this species from Schleich et al. (1996) actually reflects a mixture of Rana saharica and Rana perezi. Schleich et al. (1996) describes the morphology for R. saharica/ R.perezi as follows: The head is equally as wide as long, with an oval snout and horizontal pupils. The nostrils and upper eyelids are connected by a ridge, which continues behind the eyes, separating the flanks from the back. Males have two vocal sacs, which are protruded through slits just behind either side of the mouth. Hindfeet are webbed, and the digits often have small bulges at the termini. The skin is granular on the posterolateral venter (sides) and the posterior margins of the thighs. Males have thicker arms and nuptial pads on the innermost finger (Schleich et al. 1996).
The description of color and pattern for R. saharica /R. perezi almost certainly reflects a mixture of taxa (Schleich et al. 1996). Thus it is not clear to what extent the pattern and color elements reflect within-taxon variability. Coloration is reported to be green, brown, or mixed; a yellow or green vertebral line may be present or absent; spots may be present or absent, and if present may be random or symmetrical. However, spots (bars) on the limbs are always present (Schleich et al. 1996).
The taxonomic status of Rana saharica and the closely related Rana perezi has been under debate. Mitochondrial data show that Rana saharica and Rana perezi are closely related but genetically distinct, with R. saharica occurring in NW Africa (Morocco, Tunisia, Algeria) and R. perezi on the Iberian peninsula (Harris et al., 2003). Within Rana saharica, both allozyme and mitochondrial data indicate that there are two distinct clades: R. s. saharica, from Algeria, and R. s. riodeoroi, from Morocco (Arano et al. 1998; Harris et al. 2003).
A medium-sized frog; the largest examined specimen from Egypt has SVL of 60 mm. Snout obtusely pointed; back with two rather indistinct, longitudinal, dorso-lateral ridges; hind limbs long, with extensive webbing between digits. Males with paired vocal sacs in slits running from corner of the mouth to the base of the forelimb. Dorsum greenish, with a few rather large, round, darkish spots; limbs with a few indistinct dark bands. Ventral sides whitish. Call characteristics: average pulse groups/call = 9.83; average pulses/pulse group = 8.26; average call duration = 547.78 ms.
Distribution and Habitat
Rana saharica occurs in North Africa, in Morocco, Tunisia, and Algeria (Schleich et al. 1996). It has also been reported to occur in Egypt, although it appears to be uncommon there (IUCN 2006). R. saharica is distributed from around the Mediterranean Sea down to the northern edge of the Sahara desert. This frog is ecologically versatile, making use of habitats ranging from alpine to pre-desert (Esteban et al. 1999). It lives in the vicinity of water bodies, both natural and manmade, ranging from lakes, ponds and puddles to flowing streams and rivers, and will tolerate polluted waters (Schleich et al. 1996). Within arid areas, it makes use of manmade water bodies such as irrigation ditches or reservoirs (Schleich et al. 1996).
Distribution in Egypt
Apparently restricted to Siwa Oasis.
Morocco, Algeria, Tunisia, Libya, and Egypt.
Habitat and Ecology
Canals, drainage ditches, water pools, and other freshwater sources. Found in highly isolated localities in the Sahara, where it survives in very small water bodies, such as wells and cisterns, usually in oases. Also found in fairly mesic situations in areas overlooking the Mediterranean in northwest Africa.
Molecular Biology and Genetics
Statistics of barcoding coverage: Pelophylax saharicus
Public Records: 0
Specimens with Barcodes: 117
Species With Barcodes: 1
IUCN Red List Assessment
Red List Category
Red List Criteria
- 2004Least Concern
Status in Egypt
Common and localized.
Life History, Abundance, Activity, and Special Behaviors
Rana saharica is unusual in that it appears to have minimal or no estivation (i.e., it does not undergo an extended period of inactivity in the summer), unlike other frogs from arid areas (Schleich et al. 1996; Esteban et al. 1999). Bone growth measurements confirm this lack of a resting period (Esteban et al. 1999). Life expectancy for this species is reported to be six years (Esteban et al. 1999).
Reproduction typically begins in the second year of age. However, some R. saharica individuals (from both sexes) reach sexual maturity in their first year, at a minimum size of about 40 mm (Esteban et al. 1999). Breeding males are territorial and maintain distances of up to 2 meters, with a minimum of 50 cm (Schleich et al. 1996). R. saharica appears to have an extended breeding season. Esteban et al., (1999) found that their sample locality contained tadpoles of all stages (including metamorphic ones) and adult female frogs with oocytes of varying degrees of maturity. This species is predominantly aquatic. Rana saharica searches for prey in and around open water, but will also venture into nearby gardens and fields. The adult diet includes insects, fish eggs, frog eggs and fish fry, as well as one report of a 30 cm snake. Consumption of smaller conspecifics has been reported in captivity (Schleich et al. 1996).
This frog is quite abundant in the Maghreb (Schleich et al. 1996).
Life History, Abundance, Activity, and Special Behaviors
Schleich et al. (1996) noted that Rana saharica was the most common amphibian in the Maghreb, as well as having high population densities. Fragmentation of populations may have a negative local impact, as well as loss of aquatic habitat, particularly in areas prone to drought (IUCN 2006).
The Sahara Frog (Pelophylax saharicus) is a species of frog in the family Ranidae. It is native to Algeria, Egypt, Libya, Morocco, Spanish North Africa, Tunisia, and Western Sahara; it has also been introduced to Gran Canaria. In French it is called grenouille verte d'Afrique du Nord, and in Spanish it is known as rana verde norteafricana. Its natural habitats are rivers, freshwater lakes, arable land, ponds, and irrigated land.
- Donaire-Barroso, D., Martínez-Solano, I., Salvador, A., García-París, M., Gil, E.R., Tahar, S. & El Mouden, E.H. 2004. Rana saharica. 2006 IUCN Red List of Threatened Species. Downloaded on 23 July 2007.
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