Parasitology

Biography

Biography: Hoda Saady Mohamadain

Abstract

Siganus rivuatus, Siganus  luridu and  Siganus  sutor are common  fishes in the red sea. In our study and during a survey of red sea fish parasites ( exactly in the region of  Northern Red Sea, Of Sharm El-Naga, Makadi Bay, Southern Hurghada, Egypt.) 94 fishes were examined  (70 Siganus rivuatus, 8 Siganus luridu and 16 Siganus  sutor ) by routine Parasitology methods. 48 out of 94 fish were found to be naturally infected by Hexangium sigani Goto &Ozaki,1929 (44 Siganus rivuatus, 2 Siganus luridu and 2 Siganus  sutor ) .The encountered parasites were described morphologically and morphometrically by means of light and scanning electron microscopy The previous comparison among all described forms of H. sigani revealed some morphological variations confined between; absence or presence of tegumental spines, testes arrangement and larger or smaller of body dimensions and ovary size. these differences are considered to be of minor importance. The present study using SEM revealed presence of one main tegumental structures, sensory papillae, which are differentiated into three forms; oral papillae, genital papillae and body papillae. Each form exhibited a moderately wide range of variations both in size and in distribution. The presence of different types of sensory papillae on different locations over body tegument of H. sigani may reflect a variation in the functions they performed .  SEM study of this parasite was done for the first time in Egypt with addition of many ultrastructural details; most of which are of taxonomical importance. Also, for the first time, Siganus luridus represened a new hos record of H. sigani .                                                                                       

Keywords:  Trematoda, Microscaphidiidae , Hexangium sigani Goto &Ozaki,1929  , Siganus spp.  Red Sea Fishes.