The International Society of Protistologists, the recognised body for taxonomy of protozoa, recommended in 2012 that the term Unikont be changed to Amorphea because the name "Unikont" is based on a hypothesized
synapomorphy that the ISOP authors and other scientists later rejected.[1][5]
Further work by Cavalier-Smith showed that Sulcozoa is
paraphyletic.[10] Apusozoa also appears to be paraphyletic.
Varisulca has been redefined to include planomonads,
Mantamonas and
Collodictyon. A new taxon has been created -
Glissodiscea - for the planomonads and
Mantamonas. Again, the validity of this revised taxonomy awaits confirmation.
Amoebozoa seems to be monophyletic with two major branches:
Conosa and
Lobosa. Conosa is divided into the aerobic infraphylum
Semiconosia (
Mycetozoa and
Variosea) and secondarily anaerobic
Archamoebae. Lobosa consists entirely of non-flagellated lobose amoebae and has been divided into two classes:
Discosea, which have flattened cells, and
Tubulinea, which has predominantly tube-shaped pseudopodia.[11]
Clade
The group includes
eukaryotic cells that, for the most part, have a single emergent
flagellum, or are amoebae with no flagella. The unikonts include
opisthokonts (
animals,
fungi, and related forms) and
Amoebozoa. By contrast, other well-known eukaryotic groups, which more often have two emergent flagella (although there are many exceptions), are often referred to as
bikonts. Bikonts include
Archaeplastida (plants and relatives) and
SAR supergroup, the
Cryptista,
Haptista,
Telonemia and
picozoa.
Cavalier-Smith[2] originally proposed that unikonts ancestrally had a single flagellum and single
basal body. This is unlikely, however, as flagellated opisthokonts, as well as some flagellated Amoebozoa, including Breviata, actually have two basal bodies, as in typical 'bikonts' (even though only one is flagellated in most unikonts). This paired arrangement can also be seen in the organization of
centrioles in typical animal cells. In spite of the name of the group, the common ancestor of all 'unikonts' was probably a cell with two basal bodies.
References
^
abcAdl SM, Simpson AG, Lane CE, Lukeš J, Bass D, Bowser SS, Brown MW, Burki F, Dunthorn M, Hampl V, Heiss A, Hoppenrath M, Lara E, Le Gall L, Lynn DH, McManus H, Mitchell EA, Mozley-Stanridge SE, Parfrey LW, Pawlowski J, Rueckert S, Shadwick RS, Schoch CL, Smirnov A, Spiegel FW (September 2012).
"The revised classification of eukaryotes". J Eukaryot Microbiol. 59 (5): 429–93.
doi:
10.1111/j.1550-7408.2012.00644.x.
PMC3483872.
PMID23020233.