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A Two-Headed Green Sea Turtle (Chelonia mydas) Hatchling on Samandağ Beach, Turkey

Bektaş Sönmez, Mehmet Sert, Senem Kayıkçı, Özay Bedirci, Şükran Yalçın Özdilek


A two headed green sea turtle (Chelonia mydas) was found on Samandağ Beach, Turkey in 2015 nesting season. The two heads were anatomically similar with independent reaction to external stimuli. The carapace scutes showed anomalies. Radiography was performed and the spinal column was seen to bifurcate in the area close to the caudal region. In the post mortem examination, esophagus, stomach, liver, lung, heart and trachea were duplicated. The two headed green turtle was subclassified as teratodidymus. Dicephalism rarely occurs in sea turtle and perhaps genetic factors may play a significant role for this two headed green sea turtle.


dicephalism; anatomy; green turtle; morphology

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