In this study, a totally 103 (53♀♀, 50♂♂) C. trutta and 82 (67♀♀, 15♂♂) C. umbla samples from the Tigris River between Ilısı Dam and Cizre town were collected and ages of scales taken from front and upper section of line lateral of dorsal fins of fishes were determined and one scale from each fish sample photographed by an Olympus digital camera with Canon SX7 model binocular under the same conditions with 40X magnification and then six landmarks were taken by tpsDig. After GPA (General Procrustes Analysis) performed, ANOVA (Analysis of Variance), PCA (Principal Component Analysis), CVA (Canonical Variance Anlysis) and DFA (Discriminant Function Analysis) analysis were conducted by MorphoJ and PAST. In CV (Canonical Variance) Analysis, the permutation p-value of the mahalanobis and procrustes distance between the two species (p<.0001) shows that the difference is quite significant. As a result of the reclassification done by the analysis, we see that 79% of C. umbla and 77% of C. trutta are classified correctly.

Conjoined twinning is a rarely existed gross malformation in natural conditions. The term refers to the two individuals united at any part of their bodies. The extraordinary incidences of conjoined twinning cases may reflect important problems on the marine environment. Therefore, the purposes of this study were to report the incidences of Trachurus mediterraneus conjoined twins in Bandırma Bay, Southern Marmara Sea and to discuss the possible causes of them to derive new research questions. Four polyembryonic individuals were collected from three stations of Bandırma Bay Ichthyoplankton Survey in June 2012. The anomalous individuals were observed at the stations, St-9, 10 and 13 (Critical Stations). St-9 was at about 20m depth contour between Karşıyaka town and Dalyan village in western coasts of bay. St-10 and 13 was off Yenice village at about 10 and 30m depth contours respectively in the eastern coasts of the bay. The surface temperature, salinity, dissolved oxygen and pH of critical stations were seemed to be normal. Therefore the pollution was considered as the most possible reason of these incidences.