Scanning electron microscope study of radulae in Haliotis asinina Linnaeus, 1758 and Haliotis ovina Gmelin, 1791 (Gastropoda: Haliotidae)

Abstract

The middle parts of the radula ribbon of 10 mature snails of Haliotis asinina and Haliotis ovina were studied by scanning electron microscopy. In each transverse row, the numbers of the central and lateral teeth of H. asinina and H. ovina are 1 and 10, respectively. The number of the marginal teeth of H. asinina and H. ovina ranges from 108 to 128 and 214 to 236, respectively. The central and lateral teeth of Haliotis spp. are unicuspid. The marginal teeth of Haliotis spp. are multicuspid. In H. asinina, the anterior cusps are broad, short, and blunt ended in the central and first lateral teeth; long, narrow, and tapered in the second lateral tooth; spade shaped in the third to fifth lateral teeth; and with one large central and several lateral denticles on the marginal teeth. The radula morphologies of H. asinina and H. ovina are basically the same, with the differences in the middle part of the base of the central tooth, the size of the central tooth, the shape of the first and second lateral teeth, and the shape of the lateral denticles of the marginal teeth.