Differences between dinoflagellates and euglenoids are
Dinoflagellates :
They are mostly marine.
They have a cell wall with stiff cellulose plates on the outer surface.
They are always photoautotrophic.
They have two flagella, one transverse and one longitudinal.
Euglenoids : .
They are freshwater forms found in stagnant water.
They have no cell wall, but pellicle which give shape and flexibility to body.
They may be photoautotrophic or heterotrophic.
They have two flagella and both are anterior.