Measured and counted morphological characters of Trichodina unionis. (A) Morphological characters of the aboral side, (B) morphological characters of a denticle with the bold arrow indicating the distinctive bend angle on the blade margin, and (C) denticle arrangement. Abbreviations are as follows: Ant.: anterior side; ADD: adhesive disc diameter; BD: Body diameter; BMW: Border membrane width; CA: Cilia area; D: denticle; Dis.: Distal end; DRD: Denticular ring diameter, BL: Blade length; DL: Denticle length; DS: Denticle span; LCD: Length of central part of denticles; Post.: Posterior side; Prox.: Proximal end; R: Radial pin; RL: Ray length.