Document Type : Original Article


Department of Biology, Faculty of Sciences, Golestan University, Gorgan, Iran


The skeletochronological technique has been used to estimatethe age of the Persian pond turtle in the north of Iran. In this study, the phalange and femur bones were removed, decalcified in chloric acid, and sections stained with Hematoxylin-Eosin. The age of the specimens was determined by the number of lines of arrested growth (LAGs) in cross sections. Additionally, correlation between age and eight morphometric characters of E. o. persica were analysed using Pearson correlation. The skeletochronology results showed the mean age in the specimens (n=23) from the Golestan, Mazandaran and Guilan provinces were estimated four years (range= from 3 to 6) in juveniles (n=4), nine years (range from 6 to 12) in males (n=8), and 9.5 years (range from 7 to 15) in females (n=11). Females were significantly longer (minimum straight carapace length (SCL1); 146.8±9.08 mm) than males (SCL1; 123.36±8.11 mm) but there was no statistically significant difference in the age structures between the sexes. Moreover, the results of correlation test shows that the correlation coefficients were not significant between morphometric characters and age (P> 0.05).


Altunisik A., Ergul T., Gul C., Özdemir N., Tosunoglu M. 2014. A skeletochronological study of the smooth newt Lissotriton vulgaris (Amphibia: Urodela) from island and mainland population in Turkey. Italian Journal of Zoology 81(3):381-388.
Arakelyan M., Ruzanna P., Ilgaz C., Kumlutas Y., Durmus S.H., Tayhan Y., Danielyan F. 2013. A skeletochronological study of parthenogenetic lizards of genus Darevskia from Turkey. Acta Herpetologica 8:99-104.
Avery H.W., Spotila J.R., Congdon J.D., Fischer R.U., Standora E.A., Avery S.B. 1993. Roles of diet protein and temperature in the growth and nutritional energetics of juvenile slider turtles, Trachemys scripta. Physiological Zoology 66: 902-925
Bannikov A.G. 1951. Materialy k poznaniyu biologii kavkazskikh cherepakh.[Materials to the knowledge of the biology of the Caucasian turtles]. Uchenye Zapiski Moskovskogo    Gorodskogo Pedagogiche-skogo Instituta 18:129-167.
Carr A., Goodman D. 1970. Ecologic implications of size and growth in Chelonia. Copeia 4:783-786.
Çieçek K., Kumaş M., Ayaz D., Tok C.V. 2016. A skeletochronological study of age, growth and longevity in two freshwater turtles, Emys orbicularis and Mauremys rivulata, from Mediterranean Turkey (Reptilia: Testudines). Zoology in the Middle East 62 (1): 29-38.
Curtin A.J., Zug G.R., Medica P.A., Spotila J.R. 2008. Assessing age in the desert tortoise Gopherus agassizii: testing skeletochronology with individuals of known age. Endangered Species Research 5: 21-27.
Dunham A.E., Gibbons J.W. 1990. Growth of the slider turtle. In Gibbons J.W. (Eds.), Life History and Ecology of the Slider Turtle. Washington D.C: Smithsonian Institution Press.
Erol Y. 2010. Skeletokronolojik yöntem ile Emys orbicularis (Linnaeus 1758)’in yaş tayininin belirlenmesi [Determining age structure of Emys orbicularis (Linnaeus 1758) via skeletochronology method]. Afyon Kocatepe University, Institut of Natural and Applied Science’s.
Frazer N.B., Ehrhar L.M. 1985. Preliminary growth models for green, Chelonia mydas, and log- gerhead, Caretta caretta, turtles in the wild. Copeia 1985 (1):73-79.
Fritz U. 2003.    Die  Europäische Sumpfschildkö- te. Laurenti, Bielefeld.
Fritz U., Fattizzo T., Guicking D., Tripepi S., Pennisi M. G., Lenk P., Joger U., Wink M. 2005. A new cryptic species of pond turtle from southern Italy, the hottest spot in the range of the genus Emys (Reptilia, Testudines, Emydidae). Zoologica Scripta 34: 351-371
Fritz U., Günther R. 1996. Europäische Sumpfschildkröte – Emys orbicularis (Linnaeus1758). pp. 518-534.
Gibbons J.W. 1967. Variation in growth rates in three populations of the Painted Turtle, Chrysemys picta. Herpetologica 23: 296-303.
Gibbons J.W. 1970. Reproductive dynamics of a turtle (Pseudemys scripta) population in a reservoir receiving heated effluent from a nuclear reactor. Canadian Journal of Zoology 48: 881–885.
Girondot M., Pieau C. 1993. Effects of sexual differences of age at maturity and survival on population sex ratio. Evolutionary Ecology 7: 645-650.
Halliday T.R., Verrell P.A. 1988. Body size and age in amphibians and reptiles. Journal of Herpetology 22: 253-265.
Jørgensen C.B. 1992. Growth and reproduction. In: Feder M.E., Burggren W.W. (Eds), Environmental physiology of the amphibians, Chicago University Press, Chicago, pp. 439-467.
Kami H.G., Hojati V., Pashaee Rad S., Sheidaee M. 2006. A biological study of the European pond turtle, Emys orbicularis persica, and the Caspian pond turtle, Mauremys caspica caspica, in the Golestan and Mazandaran provinces of Iran. Zoology in the Middle East 37: 21-28.
Keller C., Andreu A.C., Ramo C. 1998. Aspects of the population structure of Emys orbicularis hispanica from southern Spain. In: Fritz U., Joger U., Podloucky R., Servan j.  (Eds), Proceedings of the Emys Symposium Dresden 96. Mertensiella, 10: 147–158.
Kutrup B., Özdemir N., Bülbül U., Çakır E. 2011. A skeletochronological study of age, growth and longevity of Rana macrocnemis populations from four locations at different altitudes in Turkey. Amphibia- Reptilia 32: 13-118.
Luiselli L., Amori G. 2016. Diet. In: Dodd C.K. (Eed), Reptile ecology and conservation: A handbook of techniques. Oxford University Press, Oxford, pp. 97-109.
Makovický P., Kopecky O., Makovický P., Matlach R. 2015. The using of skeletochronology as a screening method for age determination of Alpine newts (Mesotriton alpestris): A Technical Report. Acta Universitat is Agriculturae et Silviculturae Mendelianae Brunensis 63 (2): 439-446.
Matthews K.R., Miaud C. 2007. A skeletochronological study of the age structure, growth, and longevity of the mountain Yellow-legged frog, Rana muscosa, in the Sierra Nevada, California. Copeia 4: 986-993.
McCreary B., Pearl C.A., Adams M.J. 2008. A protocol for aging anurans using skeletochronology. U.S. Geological Survey Open-File Report 2008-1209, 38 p.
Mitrus, S., Zemanek M. 2004. Body size and survivorship of the European pond turtle Emys orbicularis in Central Poland. Biologia Bratislava 59: 103-107.
Nayak S., Mahapatra P.K., Mishra S., Dutta SK. 2007. Age determination by skeletochronology in the common Indian toad Bufo melanostictus Schneider, 1799 (Anura: Bufonidae). Herpetozoa 19 (3/4): 111-119.
Parmenter R.P. 1980. Effects of food availability and water temperature on the feeding ecology of pond sliders (Chrysemys s. scripta). Copeia 1980: 503–514.
Rhodin A.G.J., Iverson J.B., Bour R., Fritz U., Georges A., Shaffer H.B., van Dijk P.P. 2017. Turtles of the World: Annotated Checklist and Atlas of Taxonomy, Synonymy, Distribution, and Conservation Status (8th Ed.). In: Rhodin A.G.J., Iverson J.B., van Dijk P.P., Saumure R.A., Buhlmann K.A., Pritchard P.C.H., Mittermeier R.A. (Eds). Conservation Biology of Freshwater Turtles and Tortoises: A Compilation Project of the IUCN/SSC Tortoise and Freshwater Turtle Specialist Group. Chelonian Research Monographs 7:1–292.
Rodríguez-Caro R., Graciá E., Dos Santos R.M., Anadón J.D., Gimenez A. 2015. One scute ring per year in Testudo graeca. A novel method to identify ring deposition patterns in tortoises. Acta Herpetologica 10 (2): 77-84.
Schneeweiss N. 2004. Age structure of relict populations of the European pond turtle (Emys orbicularis) at the northwestern boundary of its range. Biologia, Bratislava 59(14): 123-129.
Shcherbak N.N. 1966. Zemnovodnye ipresmy- kayushchiesya Kryma.Herpetologia Taurica [Amphibians and Reptiles of the Crimeal, Herpetologia Taurica]. Naukovadumka, Kiev pp 240.
Shine R. 1979. Sexual selection and sexual dimorphism in the Amphibia. Copeia 2: 297-306.
Sinsch U., Dehling J.M. 2017. Tropical anurans mature early and die young: Evidence from eight Afromontane Hyperolius species and a meta-analysis. PlOS One 12(2): e0171666.
Tsiora A., Kyriakopoulou P. 2002. A skeletochronological study of age and growth in relation to adult size in the water frog Rana epeirotica. Zoology 105:55-60.
Xenopoulos M.A., Schindler D.W. 2001. The environmental control of near-surface thermoclines in boreal lakes. Ecosystems 4: 699-707.
Yazarloo M, Kami H.G, Bagherian Yazdi A. 2019. A skeletochronological study of age in the Caspian pond turtle (Mauremys caspica caspica) in Golestan province of Iran (Testudines: Geoemydidae). Caspian Journal of Environmental Sciences 17 (3).
Zivari S., Kami H.G. 2017. Skeletochronological assessment of age in the Persian mountain salamander, Paradactylodon gorganensis (Clergue-Gazeau and Thorn, 1979) (Caudata: Hynobiidae) from Golestan Province, Iran. Caspian Journal of Environmental Sciences 15(1): 75-84.
Zug G.R. 1991. Age determination in turtles. SSAR Herpetol, Circular 20:1-28.
Zug GR, Wynn A.H., Ruckdeschel C. 1986. Age determination of loggerhead sea turtles, Caretta caretta, by incremental growth marks in the skeleton. Smithsonian Contributions to Zoology 427: 1-3.