We estimated age of the Caspian pond turtle, Mauremys caspica caspica in Golestan Province with the skeletochronological method, using specimens collected by nets in natural habitats such as ponds and fish farms. In adult M. c. caspica, lines of arrested growth (LAGs) were clearly discernable in the phalangeal and fibula bone cross-sections. The median age of M. c. caspica in the examined Golestan Province population (n = 22) was calculated 9. 6 years (4-12) in males (n = 10), and 10. 16 years (4-13) in females (n = 12) for the first time. The maximum straight carapace length (SCL2) was in the range of 83. 74– 221. 41 (mean ± SD = 178. 39 ± 48. 89) mm in males and 103. 02– 236. 84 (193. 52 ± 41. 32) mm in female specimens. Significant correlation was found between body size and age (p < 0. 001). No difference was found in age composition between the sexes. Our study showed that skeletochronological method can be successfully applied to the Caspian pond turtle based on the clear arrest of growth in the hibernation period.

Caspian Pond Turtle of Khouzestan Province belongs to Geoemydidae family of pond turtles and Mauremys caspica siebenrocki subspecies. This species have seen in fresh water habitats such as main rivers in this province. In this study which was continued from winter 2010 to fall 2010, for morphometric study of Caspian pond turtle in Khouzestan province, 44, 54 and 36 samples of Caspian pond turtle collected from Dez, Karoun and Karkhe rivers respectively. Generally, 107 samples from all of the samples were female and 27 samples of them were male. The ratio of male samples to female samples in these rivers was 1 to 4. Also the samples which were captured in Summer, Fall and Spring were 63, 46 and 25 respectively. According to the results of Kolmogorov Smirnov Test, among 12 morphometric characteristics of Caspian turtle only two characteristics, CCL and CCW showed unormal distribution (P-value<0.05) and in other characteristics, normal distribution were seen.

Background and aims: Antioxidant defense plays a vital part in organism protection against oxidative stress which is produced by reactive oxygen species (ROS). Oxidative stress represents a serious threat to the animals facing with heavy metals. This study was designed to analyze the habitat suitability for Caspian pond turtles, namely, Mauremys caspica in Mazandaran province by measuring lead (Hg) and mercury (Pb) tissues concentrations and heavy metals’ effects on the health status of Caspian pond turtles through quantifying the oxidative stress factors. Methods: Hg and Pb were measured in kidney and liver tissues of 20 sampled Caspian pond male turtles (treatment group) using atomic absorption spectrometry (AAS) and a Caspian pond male turtle was included in the control group. Moreover, glutathione (GSH) level, catalase (CAT), and superoxide dismutase (SOD) activities were investigated in kidney and liver tissues. Results: The mean (SD) concentration of Pb and Hg were 35. 83 (4. 20), and 0. 604 (0. 03) mg/kg for the sampled livers and also 31. 01 (3. 42) mg/kg and 0. 316 (0. 04) mg/kg for the sampled kidneys, respectively. Levels of trace elements, CAT, and SOD activities were found to be higher in the liver. Totally, GSH levels, as well as, CAT, and SOD activities were found to be higher and lower, respectively, in the control turtle as compared with the contaminated Caspian pond turtles. Trace-element levels had a positive correlation with CAT and SOD activities while having a negative association with GSH levels in contaminated Caspian pond sampled turtles. Conclusion: According to the results, it was inferred that high Hg and Pb concentrations in the turtles were due to the heavy metal contamination of their habitat in Mazandaran province. Based on the positive correlation between the heavy metal concentration of the tissue and dysfunction of oxidative stress defense markers, it can be concluded when the Caspian pond turtles are faced with heavy metal contamination risk, these markers can act as a bioindicator of their health status. No doubt, more studies are required to prove this hypothesis.

The Caspian pond turtle of the northern part of Iran belonging to subspesies, Mauremys caspica caspica. In this research, 111 specimens were collected from19 stations in Golestan and Mazandaran provinces during 1999-2001. Were Studied in terms of their biology and morphometry. Coloration of body is dark olive with yellow strips and the flat carapace has 2 pygal scutes.The bridges between carapace and plastron are bony; Plastron with axillary and inguinal scutes. The suture between abdominal scutes is Longer than the suture between anal scutes and the end of analscutes is mecrunate. The males and females are distinguishable, with difference of anus position on the tail. Fore and hind limbs have swimming membranes and 5 and 4 claws respectively. This species is carnivorous and lays almost 4 or 5 eggs every year and length of the largest one is equal to 38.7mm and width is equal to 24.lmm. Statistical results showed that 77.5% of males and females are different in measured traits. In males, maximum straight carapace length frequency (44%) was between77.62- 100.98 and in females (50%) was between 54.26-77.62. In this research sexual ratio (male / female) was 1/3.

Caspian pond turtle, Mauremys caspica shows allometric growth and sexual dimorphism in the shell. Differences in allometric growth produce sexually dimorphic adults. Our results revealed that females are smaller than males that may be related to the risk of the predation, desiccation, and thermal stress. Allometric changes in shape of the shells are different between males and females. In females shape related characters such as plastral length (Pl1) and plastral fore and hind lobe width (PFLW, PHLW), gular, pectoral, abdominal and anal seam length (GSL, PSL, AbSL, AnSL) which represent width of plastron and plastral length proportionally change with size (related to SCL2 as index of size). The most remarkable changes related to size are right and left bridge length (RBr, LBr) in females but these changes have not effect on shell shape. For males character TL2 changes dramatically related to size (SCL2). Sexual dimorphism of the shell was also evident. ANCOVA indicated that the regression slopes of males and females differed significantly (p> 0. 000) in 15 of the 24 characters examined.

The turtles of Emydidae family in the northern Iran includes two species, Emys orbicularis and Mauremys caspica. In the present research, 200 specimens were collected from 25 different stations in Golestan and Mazandaran provinces during 1999-2001 and were biologically studied in terms of morphology, parasitology, feeding, reproduction and behaviour. Emys orbicularis coloration is dark olive with yellow spots, the bridges between carapace and plastron are cartilagenous and the interabdominal suture is shorter than interanal suture. It lays about 7 eggs every year, on average. Mauremys caspica coloration is dark olive with yellow parallel stripes, the bridges between carapace and plastron are bony, the anal plate is pointed and the interabdominal suture is longer than interanal suture. It lays about 4 or 5 eggs every year, on average. Both species are carnivorous and the males are more aggresive. Turtle leech, Haementeria costata, belonging to the order Rhynchobdellida was observed in some specimens of Emys orbicularis. Comparison of TL1 and TL2 in studied samples shows that anus position is different in males and females. In Emys orbicularis, 91% of males and females and in Mauremys caspica 77.5% of them are different in measured traits.

Objective-The intention of this research is studying the full topographic characteristics of the lower respiratory tract consist of lungs, bronchi, and trachea in Caspian pond tortoise, especially those features that are applicable in clinical examination, and their proximity to other organs. Design-Experimental study. Animals-Six female adult Caspian Pont turtles (Mauremys Caspica) Procedures-Siemens Somatom spirit Dual Slice computed tomography (CT) scan machine has been used. The samples were fixed in ventral recumbency to take CT-scan images. In each sample, the CT-scan was done in both fixed limb and neck and extended form. Some morphometric parameters like the volume of the coelomic cavity, right and left lungs, and others were measured through the Syngo MMWP VE40A software. Results-Trachea passing a short distance in the midline of the neck, and deviated to the left; then, it entered to the coelomic cavity. The tracheal bifurcation site was movable and move to caudal parts with neck flexion. The entrance site of the bronchi to the lungs was fixed. With the consideration of coelomic cavity volume and various parts of that in the neck extended position, the lungs consist of 42. 12% of the coelomic cavity and 22. 58% in the flexed neck position. Conclusion and Clinical Relevance-According to the observations, we can say the flexion of the neck leads to some alterations in the tracheal bifurcation site and locating posteriorly to the lungs hilum. As a result, the way of the bronchus changes to inter the lungs. The branches of bronchus in these turtles also are like other reptiles, and it's not similar to a bronchial tree and it contains just limited small branches. The CT-scan is applicable for alive animals, so this is one of the best choices for anatomical studies in animals who are in danger of extinction.

Although turtles are the most threatened taxonomic group within the reptile class, we have a very limited understanding of how turtles respond to climate change. Here, we evaluated the effects of climate changes on the geographical distribution of Caspian pond turtle (Mauremys caspica). We used an ensemble approach by combining six species distribution models including artificial neural network, generalized boosted model, generalized linear model, flexible discriminant analysis, random forest and multivariate adaptive regression splines. To predict the future distribution, modelling projection of MRI-CGCM3 was used for the year 2070 under four scenarios of representative concentration pathways (RCP). Based on the findings, the suitable habitat of Caspian pond turtle was estimated to be about 835941 km2 (about 8. 73%) of the study area. Our model projections showed that about 26 to 33% of the current suitable habitats will be unsuitable by 2070 due to climate change. The annual precipitation (24. 56%), precipitation of wettest quarter (24. 28%), precipitation seasonality (16. 93%) and temperature seasonality (14. 64%) had the highest contribution to model performance of Caspian pond turtles. Overall, our findings emphasize the need for a comprehensive understanding of the complex effects of climate change on the species, specially turtles.