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Description
The interorbital space is narrower than the upper eyelid; tympanum is distinct, about two third the size of the eye; fingers slender, pointed or slightly swollen at the tips, first not extending beyond second; toes are completely webbed; inner metatarsal tubercle long, conical much like a rudimentary toe; male with vocal slits under the lower jaw; dorsum with numerous scattered small smooth tubercles, sides of body rugose, ventrum smooth.
Color: Dorsum light gray, olivegreen or light brown, sometimes black, with irregular black spots. Thighs posteriorly dark with one or two yellow or white irregular longitudinal stripes; ventrum white, immaculate or with dark speckling or reticulation; vocal sacs light brown.
Tadpole: Tadpole large, with oval bulging body, broadest at midbody, venter flat. Total length of the tadpole 42-44 mm, tail 23-24 mm. The eyes are large and lateral. Tail is long, muscular, with wider dorsal and narrower ventral fins, tail tip is obtuse. The anteroventral oral disc has broad anterior labium with a single tooth row, posterior labium is narrower with two rows of teeth. The labial tooth row formula is 1/2 (Figure 6B). The teeth are arranged in a single row. A tooth is a squarish, medially curved 0.13-0.34 mm long, blunt tipped rod. The beak is broad, finely serrated. A pair of lateral thick labial palps, with blunt, cut into short papillae. The posterior labial palp extends well beyond posterior labium, is narrowly interrupted medially, while its anterior half forms an outpocket to include a patch of smaller papillae.
Dorsum of tadpole blackish with dark black blotches and spots extending onto tail and fins (Khan 1982a, 1991a).
Distribution and Habitat
Country distribution from AmphibiaWeb's database: Afghanistan, Bhutan, India, Iran, Islamic Republic of, Nepal, Pakistan, Sri Lanka
The Skittering frog is one of the most widely distributed frogs. It extends from Thailand to Nepal, throughout India, almost throughout Pakistan below 1800 m (Khan 1997c). It extends westward to Iran and Afghanistan. Its several races have been described from Pakistan. Its Saudi Arabian population was described as a distinct species, Euphlyctis ehrenbergii Peter (Balletto et al. 1985).
Life History, Abundance, Activity, and Special Behaviors
Euphlyctis cyanophlyctis is a highly aquatic and littoral frog. It remains permanently resident in different types of habitats with pooled water, in the plains and submountainous parts of Pakistan. The frog is remarkably capable of adjusting itself to the uncertain aquatic conditions in temperate arid parts of Pakistan.
Its peculiar unique habit of skittering over the water surface, is reported by the Mogul Emperor Babar in his autobiography (Beveridge 1979; Khan and Tasnim, 1989).
The frog either floats or remains squatting in the vegetation along marginal water. An intruder initiates the frog’s skipping behavior during which the flattened and inflated ventral surface of the body rests on the water surface while the push comes from the completely distended webbed feet which steer the body forward so that the frog is speedily carried to the center of the pond. When further provoked, it plunges into the depths.
The frog can tolerate a wide range of pH variations, from fresh water to considerably brackish and polluted refuse water; it thrives equally well in sewer systems of towns and cities.
Individual frogs call from permanent water bodies almost throughout the year. However, active breeding activity is initiated as early summer water temperature rises to 10-12oC (Khan and Malik 1987b). The calling males usually gather in a corner of a pond with some marginal vegetation. Some sit on the moist margin others float. The tone of call is very variable, depending on water and atmospheric temperatures, and the age and breeding state of the frogs. It is just "chuutt, chuutt, chuutt" repeated several times. Calling males are very active, calling and squeaking and continuously jumping over each other, causing commotion in the pond water. They actively assault each other in reproductive frenzy. When a pair is formed it does not leave the site. A female may pair with several males, laying eggs with each.
In Balochistan Euphlyctis cyanophlyctis breeds sympatrically with Paa sternosignata, and in northern hilly tracts with Tomopterna breviceps. Often its relatively active males pair with relatively docile frogs of these species. No eggs are known to result from such pairings (Khan 1987; Khan and Ahmed 1987).
Euphlyctis cyanophlyctis is a voracious feeder, feeding mostly on aquatic insects, beetles, tadpoles, dragonflies, grasshoppers, fry, etc. It is known to come out of the water during the night and go foraging in the surrounding grass, returning to the pond at dawn.
This tadpole remains solitary, stays most of the time at the bottom, feeds mostly on debris, almost clogging its digestive tract. Usually no fresh vegetation is detected in its digestive tract. It also feeds on dead tadpoles, drowned animals like earthworms, etc. It attacks sympatric tadpoles and feeds on them (Khan and Mufti 1995).
Euphlyctis cyanophlyctis tadpoles are most common in water bodies throughout the plains of Punjab and Sindh, from late February to mid-September.
Trends and Threats
Although the frog is very common in every type of small or large water bodies, the pollutants in water do affect the frog. Either adults are killed or migrate to new ponds. However, tadpoles and eggs perish.
The frog and its tadpoles are common in the diet of herons and other water visiting birds. It is included in the dietary of several common snakes, varanids and crocodiles.
Drainage of wetlands are direct threats to this species.
Relation to Humans
It is pest exterminator, feeds voraciously on different insects and their larvae.
Possible reasons for amphibian decline General habitat alteration and loss
Habitat modification from deforestation, or logging related activities
Urbanization
Prolonged drought
Drainage of habitat
Dams changing river flow and/or covering habitat
Subtle changes to necessary specialized habitat
Habitat fragmentation
Local pesticides, fertilizers, and pollutants
Long-distance pesticides, toxins, and pollutants
Comments
In its wide range from Arabia to Thailand, this frog has several subspecies:
Seistan: E. c. seistanica Nikolskii, 1899
Sri Lanka: E. c. typus De Silva, 1958
E. c. fulvus De Silva, 1958
E. c. flavens De Silva, 1958
Northwestern Punjab, Balochistan & Afghanistan: E. c. microspinulata Khan, 1997
Arabia: E. c. ehrenbergii was described as a distinct species, Euphlyctis ehrenbergii Peter (Balletto et al. 1985).
Karyotype number recorded for this species is 26 (Yadav and Pillai 1975).
References
Balletto, E., Cherchi, M. A., and Gasperetti, J. (1985). ''Amphibians of the Arabian Peninsula.'' Fauna Saudi Arabia, 7, 318-392.
Beveridge, A.S. (1979). Babur-Nama. Sang-e-Meel Publication, Lahore.
Khan, M.S. (1987). ''Checklist, distribution and zoogeographical affinities of amphibians and reptiles of Balochistan.'' Proceedings of the7th Pakistan Congress of Zoology, 1987, 105-112.
Khan, M.S. (1997). ''A new subspecies of common skittering frog Euphlyctis cyanophlyctis (Schneider 1799) from Balochistan, Pakistan.'' Pakistan Journal of Zoology, 29(2), 107-112.
Khan, M.S. and Ahmed, N. (1987). ''On a collection of amphibians and reptiles from Baluchistan, Pakistan.'' Pakistan Journal of Zoology, 19, 361-370.
Khan, M.S. and Mufti, S.A. (1995). ''Oropharyngeal morphology of detritivorous tadpole of Rana cyanophlyctis Schneider, and its ecological correlates.'' Pakistan Journal of Zoology, 27, 43-49.
Khan, M.S. and Tasnim, R. (1989). ''A new frog of the genus Rana, subgenus Paa, from southwestern Azad Kashmir.'' Journal of Herpetology, 23(4), 419-423.
Yadav, J.S. and Pillai, R.K. (1975). ''Somatic karyotypes of two Indian species of frogs (Anura, Amphibia).'' Cytobios, 13, 109-115.
Originally submitted by: M. S. Khan (first posted 2002-03-19)
Edited by: Vance T. Vredenburg, Joyce Gross, Michelle S. Koo (2021-11-19)Species Account Citation: AmphibiaWeb 2021 Euphlyctis cyanophlyctis: Common Skittering Frog <https://amphibiaweb.org/species/4703> University of California, Berkeley, CA, USA. Accessed Dec 22, 2024.
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Citation: AmphibiaWeb. 2024. <https://amphibiaweb.org> University of California, Berkeley, CA, USA. Accessed 22 Dec 2024.
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