Amoeba Bory de St. Vincent, 1822 (ref. ID; 4238, 4817), Ehrenberg, 1831 (ref. ID; 3693) reported year? (ref. ID; 1618) or Ehrenberg, nom. emend. 1831 (ref. ID; 3687)
Synonym; Amiba Bory, 1824 (ref. ID; 3693) reported year? (ref. ID; 1618); Chaos Linne, 1767 (ref. ID; 3693); Proteus O. F. Muller, 1786 (ref. ID; 3693) reported year? (ref. ID; 1618); Vibrio Gmelin, 1788 (ref. ID; 3693); Volvox Linne, 1760 (ref. ID; 3693)

[ref. ID; 1618]
Amoeboid; a vesicular nucleus, either with many spherical granules or with a conspicuous endosome; usually with one contractile vacuole; pseudopodia are lobopodia, never anastomosing with one another; holozoic; in fresh, brackish or salt water. Numerous species. (ref. ID; 1618)

[ref. ID; 4817]
Re-diagnosis; Commonly polypodial with one dominant pseudopodium at any one time. Cytoplasmic crystals are mainly bipyramidal in shape, with a few occasional plates. Cell membrane has discrete crinkled or wavy filaments. The inner nuclear membrane is organized into either a honeycomb-like layer or a loosely haneycomb-like layer. (ref. ID; 4817)
Type species; Amoeba proteus (Pallas, 1766) Leidy, 1878 (ref. ID; 4817)

Amoeba alveolata Mereschk., 1879 (ref. ID; 3687), Mereschkow (ref. ID; 3496) or Mereschkowsky (ref. ID; 3491, 3497, 5624)
Description; The small amoeba containing many contractile vacuoles creeps towards all directions, and usually takes a star-like form with long radial pseudopodia in pelagic condition. (ref. ID; 3497)
Measurements; Diameter without pseudopodia 17 um. (ref. ID; 3497)
Amoeba amazonas (Prescott) Friz, 1992 (ref. ID; 4817 original paper) reported author and year? (ref. ID; 4836, 4837)
Diagnosis; A small star-shaped amoeba, containing a single nucleus in the shape of a compressed spheroid and few, if any, cytoplasmic crystals. The plasma membrane is covered by thick cell coat composed of a 20 nm thick amorphous layer and an external layer of filaments, 150-200 nm long. Nuclear membrane has a prominent honeycomb-like fibrous lamina. Nucleoli are normally found at the periphery of the interphase nucleus with a substructure similar to A. proteus. RNA containing helices are present within the nucleoplasm. Mitochondria are unusual in having variable pattern of either plate-like and tubular cristae whereas the Golgi bodies have a greater proportion of vesicles and a smaller number of cisterni. Nucleus and cytoplasm are incompatible by transplantation with those of A. proteus. Generation time was less than 24 h at 23 degrees C. Isozymic analyses showed similarity coefficients between 0.40 and 0.70 with strains of A. proteus, A. borokensis, and A. carolinensis. (ref. ID; 4817)
Amoeba borokensis Page, 1986 (ref. ID; 4722 original paper) reported author and year? (ref. ID; 4817, 4836, 4837)
Diagnosis; Locomotive form commonly polypodial though often monopodial, with length approximately 210-545 um, mean approximately 370 um in culture. Nucleus usually a compressed sphere or ovoid, with greatest diameter usually 23-37 um, mean 29 um. Majority of cytoplasmic crystals thick rectangular plates, often square. Fine structure similar to that of A. proteus, with filamentous coat often preserved as a loosely matted filamentous layer about 100-130 nm thick; inner lamina of nuclear envelope in form of hexagonal prisms (honeycomb); nucleolar material in many pieces around periphery of nucleus. Nucleus and cytoplasm incompatible, by transplantation, with those of A. proteus and A. leningradensis. DNA content of nucleus approximately half that of A. proteus. Generation time under favourable conditions less than 24 h. Electrophoretic pattern of total proteins quantitatively different from that of A. proteus, different from that of A. leningradensis. (ref. ID; 4722)
Remarks; With the light microscope this strain could be consistently and objectively distinguished from all strains of A. proteus with which it was compared by two features: the diameter and shape of its nucleus, and the form of its crystals. In amoebae of the Bor strain (Amoeba borokensis), the majority of cytoplasmic crystals were plate-like, either square or rectangular, although some bipyramidal crystals were present. The crystals were contained in vesicles, commonly one per vesicle but occasionally 2 or 3 of different sizes in a vesicle. Square plates reached a maximum diameter of about 4.5 um, long rectangles a length rarely more than 9 um, and bipyramidal crystals a maximum length of about 5.5 um. The relative numbers of the two crystalline forms (bipyramids a small minority) appeared similar whether the amoebae were from Tetrahymena-fed cultures or from cultures containing Chilomonas set up to test the latter method of culture. (ref. ID; 4722)
Known habitat; Fresh water, northern USSR. (ref. ID; 4722)
Type specimens; Type slides deposited in British Museum (National History): Holotype, 1985:7:1:1; paratype, 1985:7:1:2. (ref. ID; 4722)
Amoeba carolinensis (Hegner & Taliaferro, 1924) Short, 1946 (ref. ID; 4817) reported author and year? (ref. ID; 4836)
Description; Multinucleated, giant amoeba with locomotive forms 0.3-3 mm in length, and discoid shaped nuclei 22-30 um in diameter. Golgi bodies, mitochondria and rough ER are identical to these structures in A. proteus. The nuclei and cytoplasm are incompatible by nuclear or cytoplasmic transfer with A. proteus. Similarity coefficients were between 0.40 and 0.70 by isozymic analyses with strains of A. proteus, A. amazonas and A. borokensis indicating an intrageneric relationship with these 3 Amoeba species. (ref. ID; 4817)
Amoeba discoides Schaeffer, 1917 (ref. ID; 3687) reported year? (ref. ID; 1618) reported author and year? (ref. ID; 4672, 4837)
See; Metachaos discoides
Description; A few blunt, smooth pseudopodia; crystals abundant, truncate bipyramidal, about 2.5 um long (Schaeffer); endoplasm with numerous coarse granule; fresh water. (ref. ID; 1618)
Measurements; About 400 um long during locomotion. (ref. ID; 1618)
Amoeba dubia Schaeffer, 1916 (ref. ID; 1335) reported year? (ref. ID; 1618) reported author and year? (ref. ID; 4672)
See; Polychaos dubium
Description; Numerous pseudopodia flattened and with smooth surface; crystals, few large, up to 30 um long and of various forms among which at least four types are said to be distinct (Schaeffer); contractile vacuole one or more; fresh water. (ref. ID; 1618)
Measurements; About 400 um long. (ref. ID; 1618)
Amoeba fibrillosa Greeff, 1891 (ref. ID; 2713) and Amoeba alba Greeff, 1891 (ref. ID; 2713)
Description; Nominal species of questionable validity. Although Penard (1902, 1905) took up these names and applied them to 'Amibes a pellicule', there is no evidence at all that Greeff had any species of Thecamoeba before him when he described these multinucleate soil amoebae. Unfortunately, Greeff did not publish illustrations of either species, but the descriptions suggest that he was dealing with species of Leptomyxa, a genus with two well-described species found principally in the soil. Greeff in fact took pains to contrast A. fibrillosa with his A. terricola, and the description of its locomotive morphology could easily be applied to Leptomyxa or another microplasmodial organism. Apart from Penard's organisms, to which he incorrectly applied these names of Greeff, no multinucleate Thecamoeba has ever been described. However, in view of the rarity of the multinucleate species Chaos carolinense (Wilson, 1900), the absence of reported findings other than Penard's is not food evidence that no multinucleate Thecamoeba exists. (ref. ID; 2713)
Amoeba gorgonia Penard, 1902 (ref. ID; 3687, 3693 original paper) reported year? (ref. ID; 1315, 1618, 6675)
Description; Body globular when inactive with a variable number of radiating "arms", formed on all sides; when in locomotion, clavate; nucleus vesicular, with a large endosome; fresh water among vegetation. (ref. ID; 1618)
Measurements; Rounded forms 40-50 um in diameter; clavate individuals up to 100 um. (ref. ID; 1618)
Amoeba guttula Dujardin, 1823 (ref. ID; 3693) or 1841 (ref. ID; 3687) reported year? (ref. ID; 1315, 1618)
Syn; Amiba guttula Dujardin, 1841 (ref. ID; 1315, 3687); Amoeba guttula Perty, 1852 (ref. ID; 1315)
Description; Ovoid during locomotion, narrowed posteriorly and often with a few minute, nipple-like dentations; movement by wave-like expansions of ectoplasm; endoplasm granulated, with crystals; nucleus vesicular; a single contractile vacuole; fresh water in vegetation. (ref. ID; 1618)
Measurements; 30-35 by 20-25 um. (ref. ID; 1618)
Amoeba horticola Nagler (ref. ID; 3497)
Description; The small form has a few broad pseudopodia and a well-developed transparent ectoplasm. The nucleus is comparatively large, and has an endosome clear in the center. Contractile vacuoles are always absent. (ref. ID; 3497)
Measurements; Length without pseudopodia 20-30 um. (ref. ID; 3497)
Amoeba leningradensis Page & Kalinina, 1984 (ref. ID; 4676 original paper) reported author and year? (ref. ID; 4238, 4722, 4728, 4817, 4837)
See; Metamoeba leningradensis (formerly known as the Sh strain of A. leningradensis) (ref. ID; 4817)
Diagnosis; Locomotive form often polypodial, with length approximately 160-550 um, mean approximately 360 um; nucleus a sphere which is often slightly compressed, often appearing ovoidal, with its greatest diameter 21 to 29 um, mean 25 um; many cytoplasmic crystals, mostly truncate bipyramids. Plasma membrane covered with amorphous coat 13-20 nm thick; nuclear envelope with internal fibrous lamina differentiated into hexagonal prisms, lamina usually 400 to 550 nm thick, inner diameter of each prism approximately 165 nm, nucleolar material concentrated around periphery of nucleus but also occurring in interior; Golgi bodies composed of about for flattened saccules and associated vesicles, possibly sometimes of vesicles alone. Nucleus incompatible, by transplantation, with nucleus and cytoplasm of Amoeba proteus. (ref. ID; 4676)
Known habitat; Fresh water, northwestern USSR. (ref. ID; 4676)
Type specimens; Type slides deposited in British Museum (Natural History): Holotype, 1983:1:28:1; paratype, 1983:1:28:2. (ref. ID; 4676)
Amoeba limicola Rhumbler, 1898 (ref. ID; 3687, 3693) reported year? (ref. ID; 1618)
Description; Somewhat similar to A. guttula; body more rounded; locomotion by eruption of cytoplasm through the body surface; nucleus vesicular; fresh water among vegetation. (ref. ID; 1618)
Measurements; 45-55 by 35 um. (ref. ID; 1618)
Amoeba papyracea Penard, 1905 (ref. ID; 2713)
Description; Nominal species of questionable validity. This name undoubtedly refers to a Thecamoeba, which Penard compared with A. terricola. He gave the average size of eight rounded up cells as 184 um, but the only illustration was of the nucleus, which had a layer of small granules beneath the nuclear membrane. (ref. ID; 2713)
Amoeba proteus Pallas (ref. ID; 1618) or (Pallas, 1766) Leidy, 1876 (ref. ID; 1315, 1335, 4817) or Leidy (ref. ID; 6675)
Syn; Amiba diffluens Dujardin, 1835 (ref. ID; 1315); Amiba divergens Bory de St. Vincent, 1822 (ref. ID; 1315); Amiba koeselii Crevier, 1875 (ref. ID; 1315); Amiba mulleri Bory de St. Vincent, 1824 (ref. ID; 1315); Amiba princeps Dujardin, 1841 (ref. ID; 1315); Amiba roeselii Bory de St. Vincent, 1824 (ref. ID; 1315); Ameba diffluens Maggi, 1876 (ref. ID; 1315); Amoeba chaos Leidy, 1878 (ref. ID; 1315); Amoeba communis Duncan, 1877 (ref. ID; 1315); Amoeba diffluens Ehrenberg, 1830 (ref. ID; 1315); Amoeba oblonga Schmarda, 1854 (ref. ID; 1315); Amoeba princeps Ehrenberg, 1831 (ref. ID; 1315); Amoeba roeselii Pritchard, 1852 (ref. ID; 1315); Chaos diffluens O. F. Muller, 1786 (ref. ID; 1315); Chaos protheus Linneus, 1767 (ref. ID; 1315)
Description; Creeping with a few large lobopodia, showing longitudinal ridges; ectoplasm and endoplasm usually distinctly differentiated; typically uninucleate; nucleus discoidal but polymorphic; endoplasmic crystals truncate bi-pyramid, up to 4.5 um long; nuclear and cytoplasmic divisions show a distinct correlation; fresh water. (ref. ID; 1618)
Measurements; Up to 600 um or longer in largest diameter. (ref. ID; 1618)
Amoeba radidosa Ehrenberg (ref. ID; 1618, 6675)
See; Amoeba radiosa Dujardin (ref. ID; 3693), Dactylospherium radiosum (ref. ID; 1315)
Description; Small, usually inactive, globular or oval in outline; with 3-10 radiating slender pseudopodia which vary in length and degree of rigidity; when pseudopods are withdrawn, the organism may be similar A. proteus in general appearance; pseudopods straight, curved or spirally coiled; fresh water. (ref. ID; 1618)
Measurements; Size varies, usually about 30 um in diameter, up to 120 um or more. (ref. ID; 1618)
Amoeba saphirina Penard, 1902 (ref. ID; 3687, 3693 original paper) reported year? (ref. ID; 3497)
Description; The body is delicate and changeable. The fine protoplasm is light blue, and rapidly moves into slender pseudopodia. Contractile vacuoles rarely appear. (ref. ID; 3497)
Measurements; Length without pseudopodia 18-42 um. (ref. ID; 3497)
Amoeba spumosa Gruber, 1885 (ref. ID; 3687) reported year? (ref. ID; 1618, 3693) reported author and year? (ref. ID; 3292)
Description; Somewhat fan-shaped; flattened; during locomotion broad pseudopodia with pointed end; temporary posterior region with nipple-like projections; a small number of striae become visible during movement, showing there is a very thin pellicle; endoplasm always vacuolated, the vacuoles varying in size (up to 30 um in diameter); vesicular nucleus with an endosome; fresh water. (ref. ID; 1618)
Measurements; 50-125 um long during locomotion. (ref. ID; 1618)
Amoeba striata Penard (ref. ID; 1618, 3693)
See; Thecamoeba striata
Syn; Amoeba verrucosa in Leidy Pl. III, fig. 37. (ref. ID; 3693)
Description; Somewhat similar A. verrucosa, but small; body flattened; ovoid narrowed and rounded posteriorly; nucleus vesicular; contractile vacuole comparatively large and often not spherical; extremely delicate pellicle shows three or four fine longitudinal lines which appear and disappear with the movement of the body; fresh water among vegetation. (ref. ID; 1618)
Measurements; 25-45 by 20-35 um. (ref. ID; 1618)
Amoeba verrucosa Ehrenberg, 1838 (ref. ID; 1315) reported year? (ref. ID; 1618)
See; Amoeba terricola (Ehrenberg) Penard, 1902 (ref. ID; 3693), Thecamoeba verrucosa (Ehrenberg, 1838)
Syn; Amiba verrucosa Dujardin, 1841 (ref. ID; 1315); Amoeba natans Perty, 1852 (ref. ID; 1315); Amoeba papillata Mereschkowsky, 1878 (ref. ID; 1315); Amoeba quadrilineata Carter, 1856 (ref. ID; 1315)
Description; Ovoid in general outline with wart-like expansions; body surface usually wrinkled, with a definite pellicle; pseudopodia short, broad and blunt, very slowly formed; nucleus ovoid, vesicular, with a large endosome; contractile vacuole; fresh water among algae. (ref. ID; 1618)
Measurements; Up to 200 um in diameter. (ref. ID; 1618)
Amoeba verrucosa var. maxima Playfair, 1914 (ref. ID; 2713)
Description; Nominal species of questionable validity. Apart from the fact that varietal names have no status in zoological nomenclature, Playfair's description is somewhat confusing. He stated that the usual size of Amoeba verrucosa in Australia was 50-60 um, which makes his identification of that species questionable. His 'var. maxima', the length of which was 120 um, had a central nucleolus of any other known Thecamoeba except T. orbis. He showed four parallel dorsal folds, with an outline such as sometimes occurs in T. similis. It is almost certain that this freshwater amoeba was not a T. verrucosa. (ref. ID; 2713)
Amoeba vespertilio Penard, 1902 (ref. ID; 3687, 3693 original paper, 3719) reported year? (ref. ID; 1333, 1618)
See; Now a considered a Mayorella (ref. ID; 3719)
Syn; Amoeba angulata? Mereschkovsky (ref. ID; 3693); Amoeba digitata? Parona (ref. ID; 3693)
Description; Pseudopodia conical, comparatively short, connected at base by web-like expansions of ectoplasm; endoplasm colorless, with numerous granules and food particles; a single vesicular nucleus with a large endosome; contractile vacuoles; fresh water. (ref. ID; 1618)
Measurements; 60-100 um long. (ref. ID; 1618)
Amoeba viridis Leidy, 1874 (ref. ID; 3687, 3719)
See; Mayorella viridis (ref. ID; 3719)
Description; "bright green from the multitude of contained chlorophyll balls. The form of the body is irregularly stellate, with thick conical pseudopods projecting in all directions...". (ref. ID; 3719)