The group was originally proposed in 1861 by
William B. Carpenter, who created it as a taxonomic order containing the single family Amoebina. Carpenter's Lobosa consisted of amoeboid organisms whose
endoplasm (endosarc) flows into lobe-like "pseudopodian prolongations." This type of pseudopod, which was understood to be typical of the genus
Amoeba "and its allies," differed from the
filose (thread-like) or
reticulose (netlike) pseudopods of the
Foraminifera. The name Lobosa was chosen for these amoebae "as expressing the lobe-like character of their pseudopodial extensions". As currently defined, the subphylum Lobosa includes both shelled (
testate) and naked amoebae (gymnamoebae), but excludes some organisms traditionally regarded as "lobosean", such as
Pelomyxa and
Entamoeba (Amoebozoa) and some
Heterolobosea (
Excavata). ==Phylogeny==