COMPARATIVE ULTRASTRUCTURAL STUDY OF THE SALIVARY GLANDS OF TWO HEMATOPHAGOUS LEECHES (ANNELIDA, CLITELLATA, ARHYNCHOBDELLIDA) IN IRAQ
Keywords:Annelida, Hirudo, Leeches, Limnatis, Salivary gland.
During July - August of 2021, thirty-one leeches were collected from two localities in Erbil and its suburbs for studying the morphological features of jaws, denticles, and salivary gland cells. Leeches were two blood-sucking species; Hirudo orientalis (Utevsky & Trontelj, 2005) (Family, Hirudinidae) and Limnatis paluda (Tennent 1859) (Family, Praobdellidae). The investigations conducted using a stereomicroscope (SM) and scanning electron microscopy (SEM). H. orientalis jaws were white and rigid, bearing sharp teeth, while L. paluda jaws were gray and soft bearing fewer blunt teeth with plentiful papilla and both are monostichodont. In the present study, the salivary glands of adult leeches were examined by SEM. They are composed of unicellular glands arranged in grape patterns with spherical, ovoid, and pear shapes in various cell sizes; the cell bunches of gland cells were highly developed and interconnected to one another by tiny channels. A bigger canal that led to the jaws was created by combining channels from each bunch.