Intramacronucleata

Prostomatea is a class of ciliates. It includes the genera Coleps and Pelagothrix.

The Colpodea are a class of ciliates, of about 200 species common in freshwater and soil habitats. The body cilia are typically uniform, and are supported by dikinetids of characteristic structure, with cilia on both kinetosomes. The mouth may be apical or ventral, with more or less prominent associated polykinetids. Many are asymmetrical, the cells twisting sideways and then untwisting again prior to division, which often takes place within cysts. Colpoda, a kidney-shaped ciliate common in organic rich conditions, is representative.

Intramacronucleata is a subphylum of ciliates. The group is characterized by the manner in which division of the macronucleus is accomplished during binary fission of the cell. In ciliates of this subphylum, division of the macronucleus is achieved by the action of microtubules which are assembled inside the macronucleus itself. This is in contrast to heterotrich ciliates of the subphylum Postciliodesmatophora, in which division of the macronucleus relies on microtubules formed outside the macronuclear envelope.

Armophorea is a class of ciliates in the subphylum Intramacronucleata. . It was first resolved in 2004 and comprises three orders: Metopida, Clevelandellida, and Armophorida. Previously members of this class were thought to be heterotrichs because of similarities in morphology, most notably a characteristic dense arrangement of cilia surrounding their oral structures. However, the development of genetic tools and subsequent incorporation of DNA sequence information has led to major revisions in the evolutionary relationships of many protists, including ciliates. Metopids, clevelandellids, and

thumb|224px| Two similar-looking but sexually distinct partners connected at their front ends exchange genetic material via a plasma bridge.

right|thumb|250px|Typical large Colpoda @ 400X right|thumb|250px|Measurements of large Colpoda in micrometres

Ventrata is an infraphylum of ciliates inside the subphylum Intramacronucleata that unites the classes Phyllopharyngea, Colpodea, Nassophorea, Prostomatea, Plagiopylea and Oligohymenophorea. It is equivalent to the clade CONthreeP or Conthreep recovered by phylogenetic analyses. ==Description== Members of this taxon are characterized by having, ancestrally, a ventral cytopharynx, as the name suggests. ==Phylogeny== The monophyly of CONthreeP is well supported, being placed as sister to Protocruziea. The order Discotrichida, belonging to class Nassophorea, has been recovered as the earliest bra