Opalozoa

Opalozoa is a subphylum of heterotrophic protists of the phylum Bigyra, and is the sister group to Sagenista. Opalozoans are non-photosynthetic heterokonts that are ancestrally phagotrophic but many times have evolved to be osmotrophic saprotrophs in the gut of vertebrate animals.

History: phylum Opalozoa
In 1993 the name “Opalozoa” referred to a group of protists that was very different from what it is now. It was a phylum composed of many unrelated zooflagellates, grouped together because of the common presence of tubular mitochondrial cristae and the lack of cortical alveoli or rigid tubular ciliary hairs (retronemes). It also included the opalinids, proteomyxids and plasmodiophorids.

Modern classification
The modern taxonomy of Opalozoa, down to order level, is as follows:
 * Subphylum Opalozoa
 * Infraphylum Bikosia
 * Class Bikosea
 * Subclass Bicosidia
 * Superorder Cyathobodoniae
 * Order Bicoecida
 * Order Anoecida
 * Order Pseudodendromonadida
 * Superorder Borokiae
 * Order Borokida
 * Subclass Rictidia
 * Order Rictida
 * Infraphylum Placidozoa
 * Superclass Wobblata [ paraphyletic ]
 * Class Placididea
 * Order Placidida [=Placidae ]
 * Class Nanomonadea
 * Order Uniciliatida
 * Class Opalomonadea
 * Superclass Opalinata
 * Class Opalinea
 * Order Proteromonadida
 * Order Opalinida
 * Class Blastocystea
 * Order Blastocystida
 * Opalozoa incertae sedis:
 * Pendulomonas
 * Bordnamonadidae

Phylogeny
The cladogram below shows the internal relationships of Opalozoa.