First observation on sexual dimorphisms in radula of Conomurex persicus
(Gastropoda: Strombidae)in the Mediterranean Sea

• Erhan Mutlu
• Institute of Marine Sciences, Middle East Technical University POB 28, Erdemli, 33731, Mersin, Turkey.
  Fax: +90 324 5212327
• E-mail: mutlu@ims.metu.edu.tr
• The Regional Workshop on Marine Sciences & Natural Resources 25-26 May 2004.

Dentition characters of Conomurex persicus found along the Mediterranean coasts of Turkey were analyzed. For the analyses of radula 289 individuals (34 adult males, 140 adult females and the rest of juveniles) were examined. Male and female individuals of the species had different numbers of radular cusps. The radula of taenioglossate type was made up of 2 marginal teeth, one lateral and one central (rhachidian) tooth, each being delicate with different numbers of the cusps. The central and lateral teeth of males and females had 7 cusps and 5 cusps in both males and females, respectively. Outer and inner marginal teeth of males had 2 and 1 cusps while females' had 5 and 6 cusps, respectively. The female's radula is yellow-whitish. The male's radula is reddish dark brown. Binocular examination of the radula showed that marginal teeth becoming sexually dimorphous as follows: The number of cusps on the marginal teeth of the small juveniles was 11. As the verge and shell lengths grew, the number was reduced by lessening size of the cusps and making pointed of the tooth. Ultimately, the tooth of male that feed on Corallinales algae, Jania rubens, appeared to be of a hook-like structure. Marginal tooth resemble to comb in female was flattened whereas it in male was tube-like cylinder in shape. Ratios of the longest cusps to the others on each of lateral and central teeth were greater in males than those in females. Radular ribbon of the male is wider than those of the female as a function of proboscis diameter.