Morphology study of the otoliths of the parrotfish,Chlorurus sordidus(Forsskål, 1775) andHipposcarus harid(Forsskål, 1775) from the Red Sea coast of Egypt (Family: Scaridae)

Abstract

In the present study a comparison of the otolith morphology of two species of parrotfish, family Scaridae, collected from the Red Sea coast of Egypt, is conducted to identify the most appropriate taxonomic characters that separate these species. Ontogenetic changes in the otoliths of the two scarid fishes become evident. In the otoliths ofChlorurus sordidus, the following characters are comparable in small-sized adult fishes: otolith width, otolith depth, mesial surface shape, lateral surface shape, shape of sulcus acusticus, column, rostrum and size of rostrum. The otoliths of young adults (GI)C. sordidusdiffer from the adult ones in 14 out of the 22 characteristics studied. In the otoliths ofHipposcarus harid, the following characters are comparable in small and large fish: otolith width, otolith depth, mesial and lateral surface shapes, shape of sulcus acusticus, rostrum and size of rostrum.