The general plan of Discoba structure is reduced to a dikinetid state (2–3 flagella or many pairs), while usually 3 microtubule roots depart from a pair of kinetosomes. Many taxa are characterized by trans splicing, the formation of a giant unsplitted transcript during RNA processing. Cells are usually large and in different groups are characterized by various particular adaptations, such as paraxial road, kinetoplast, or undulating membrane. Mitochondria, if present, with discoid, rarely tubular cristae, but in some taxa they are reduced to peroxisomes or mitosomes. Most species are phagoheterotrophs, feeding on cytostomes or lobopodia, but there are also osmotrophs and even autotrophic forms with chloroplasts that have a 3-membrane envelope and chlorophylls a and b (euglenoids). In many euglenoids, plastids are secondarily absent, but the ability to phagotrophy has also been lost – such forms feed osmotrophically (Rhabdomonadineae), however, some euglenoids (Peranematida) are phagotrophs and are primarily devoid of plastids. The sexual process is absent.
Jakobea is a sister/basal lineage.


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• DIAPHORETICKES [Adl et al., 2012]
•• DISCOBA [Hampl et al., 2009]
••• Percolozoa [Cavalier-Smith, 1991]
•••• Pharyngomonadea [Cavalier-Smith, Nikolaev, 2008]
•••• Tetramitia [Cavalier-Smith, 1993]
••••• Lyromonadea [Cavalier-Smith, 1993]
••••• Heterolobosea [Page, Blanton, 1985]
••• Euglenozoa [Cavalier-Smith, 1981]
•••• Kinetoplastida [Honigberg, 1963]
•••• Diplonemea [Busse, Preisfeld, 2002]
•••• Euglenophyta [Pascher, 1931]
•••• Symbiontida [Yubuki et al., 2009]
•• JAKOBEA [Cavalier-Smith, 1999]
••• Jakobida [Patterson, 1990]
••• Tsukubea [Cavalier-Smith, 2013]
•• HEMIMASTIGOPHORA [Foissner et al., 1988] inc. sedis

Rank correlation:
• ~Subdomain
•• ~ Kingdom
••• ~ Infrakingdom
••••~ Superphylum/Phylum