All euglenozoa seem to have some form of ingestion apparatus. It is evident in Bodo, the diplonemids, it is said to occur even in the green euglenids, but they are most strongly developed in the heteronematine euglenids. The mouth in these flagellates is almost always seen as two dark rods (this is the case for Jenningsia - the genus illustrated below, Peranema, Dinema, Heteronema, Ploeotia and Urceolus).
The mouths of heterotophic euglenids have two principal parts - the vanes and the rods. The vanes, usually four of them, seem to attach to the membrane of forming food vacuoles and probably act to draw food into the cell. The rods provide more structural support. They vary considerably from one species to another in the extent of their development. The ingestion apparatus of small euglenids, such as Petalomonas (left), have very few associated microtubules, while those of species that eat detritus , large bacteria, or other protozoa tend to have 'jaws' comprised of many microtubules (such as the mouth of Entosiphon on the right). Autotrophic euglenids have relatively simple mouths.
Three arrangements are common in euglenids. An arrangement where there are three support rods (Entosiphon), two support rods (Peranema and Ploeotia) and an arrangement in which the mouth structure is undulating or folded (plicate).
Click here for more details of mouths of (1) Entosiphon, (2) Peranema and (3) Ploeotia.