Sem verification of armature and chaetotaxy ofDiplostomum paracaudum(Iles, 1959) cercaria (Digenea, Diplostomidae)

Abstract

Light microscopy observations on armature and chaetotaxy of armature and outer structure of sensory cells. They show a variety Diplostomum paracaudum (I les, 1959) were veryfied in scanning in cilia length and structure of a collar. The specific distribution electron microscopy. The new findings concern some details of of particular sensilla forms is observed. Résumé : Vérification au microscope électronique à balayage de l'armature et de la chétotaxie de la cercaire de Diplostomum paracaudum (Iles, 1959) (Digenea, Diplostomidae). Nous avons vérifié au microscope électronique à balayage (MES) les observations précédentes sur l'armature et sur la chétotaxie de la cercaire de Diplostomum paracaudum (Iles, 1959). Les nou velles observations concernant certains détails sur les épines et sur la structure externe des cellules sensorielles. Mise en évidence de différences dans la longueur des cils et dans la structure du col lier. La distribution spécifique des différents types de papilles est étudiée.

Chaetotaxy and armature of Ichthyocotylurus erraticus (Rudolphi, 1809) and I. variegatus (Creplin, 1825) cercariae (Digenea, Strigeidae)

“…All of these types were visible in silver-stained preparations but could be differentiated only by SEM. This technique also enabled Niewiadomska and Nasincova (1990) to identify four forms of sensilla in the cercaria of D. paracaudum (Iles 1959). Three of their forms closely resemble those described herein: sensilla with a long cilium and a loose, short collar; sensilla with a cilium of intermediate-length; and sensilla with a short-cilium and a tight collar.…”

“…It appears that no author has thus far identified multiciliate sensory receptors for cercariae of the superfamily Strigeoidea. Niewiadomska and Nasincova (1990) have suggested that variation in the outer sensillary structure corresponds to differences in internal structure, as has been shown by TEM investigations of sensory endings of D. pseudospathaceum Niewiadomska 1984 cercariae (Czubaj and Niewiadomska 1992). Niewiadomska and Nasincova (1990) found that the distribution of different sensilla types was stable in D. paracaudum; this was also true of the species examined in the present study.…”

“…Niewiadomska and Nasincova (1990) have suggested that variation in the outer sensillary structure corresponds to differences in internal structure, as has been shown by TEM investigations of sensory endings of D. pseudospathaceum Niewiadomska 1984 cercariae (Czubaj and Niewiadomska 1992). Niewiadomska and Nasincova (1990) found that the distribution of different sensilla types was stable in D. paracaudum; this was also true of the species examined in the present study. Similarities in sensilla types between D. paracaudum and Ichthyocotylurus cercariae are not surprising if they reflect function, as in each case the next host is a freshwater fish and the life cycle is essentially similar.…”