Acrocoelus is a genus of alveolates.
This genus was named in 1999 by Fernández and collaborators.
The species in this genus are fusiform with an apical anterior concavity and a longitudinal groove. There are two anterior flagellae directed backward. The flagellae arise from parallel basal bodies in a flagellar pocket.
The single nucleus has a single nucleolus.
The cell wall is a trilaminate pellicle with subpellicular microtubules and a micropore.
The cytoplasm contains a single, branched mitochondrion with tubular cristae, a supranuclear Golgi apparatus and large amounts of glycan granules.
There are three types of secretory organelles present. Type I are round and structurally complex. These may be extrusomes. The types II and III appear to be rhoptry and microneme like organelles respectively.
The type species is Acrocoelus glossobalani <small>I.Fernández, Pardos, Jes.Benito & N.L.Arroyo, 1999</small>.