Biological aspect of the jaw system of meagre (Argyrosomus regius): New insights into jaw teeth distribution, characterization, and their relationship to its carnivorous behaviour

Abstract

Documentation on the morphological appearance of teeth and their relationship to carnivorous feeding habits was lacking. Our study was applied to twelve Argyrosomus regius using the gross scanning electron microscopic techniques to provide a detailed ultrastructural description of the jaw, its tooth arrangement, and the relationship to carnivorous feeding behavior, which had not been previously described. The upper velum's oral surface contained only taste buds. There were two teeth in the upper caudal premaxillary fangs and four in the lower. Two premaxillary teeth groups were identified: the median upper of 3–4 rows and the median lower of 4–5 rows. The lateral upper incisive group had numerous small teeth (in 3–4 rows) and the long ones in one row, while the lateral lower one was organized in two rows: large posterior and small anterior. The dental arrangement in the lateral upper premaxillary group is highly specialized, with numerous small teeth in three or four rows and long teeth in one row. In contrast, the lateral lower group exhibited a different pattern, with small, short, straight teeth arranged in groups parallel to the dental space. The upper lateral tooth band had two types: the medial lower one of long teeth, while the medial upper one of small, short teeth in four or five rows, except anteriorly in just two rows. Conclusion, the arrangement and size of teeth in fish's upper and lower jaws can reveal their diet and feeding habits, and studying tooth morphology can aid researchers in understanding their evolutionary adaptations.