Vexillifera

Vexillifera Schaeffer, 1926 (ref. ID; 2092, 4667, 4688, 7540, 7757)

Phylum Sarcomastigophora: Subphylum Sarcodina: Superclass Rhizopoda: Class Lobosea: Subclass Gymnamoebia: Order Amoebida: Suborder Conopodina: Family Paramoebidae (ref. ID; 2092)
Class Lobosea: Subclass Gymnamoebia: Order Amoebida: Family Paramoebidae Poche 1913 (= Mayorellidae Schaeffer 1926; cf. Page 1972) (ref. ID; 4667)
Class Flabellinea: Order Dactylopodida (ref. ID; 6789)
Gymnoamoebia: Paramoebidae (ref. ID; 7757)

[ref. ID; 2092]
This genus is composed of small amoebae which produce elongated, linear, or narrowly conical sub-pseudopodia from an anterior hyaline lobe. Since the sub-pseudopodia are often carried to the posterior end, amoebae of the genus have a spiny appearance somewhat similar to that of Acanthamoeba. Two freshwater species and five marine species have been described. (ref. ID; 2092)

[ref. ID; 4688]
The genus Vexillifera was established by Schaeffer (1926) for naked, lobose amebas that, like the genus Mayorella Schaeffer, 1926, form clear, conical or tapered (but round-tipped) pseudopods, but unlike Mayorella also form "long, slender pseudopods, extending from the anterior end during locomotion, which are capable of moving about in the water after the manner of tentacles." Schaeffer designated V. ambulacralis (Penard, 1890) as the type species; but Penard designated 2 apparently different organisms but that name, first one (Penard 1890) and then another, later (Penard 1902). The later organism he depicted as waving its long, slender, clear pseudopods by bending them at the bases prior to or during their retraction. Bovee (1951) proposed that those Mayorella-like amebas that form such clear, slender, tapered pseudopods and wave them by basal bending prior to retraction should be placed in the genus Vexillifera. Other amebas that form pseudopods that are indeterminate in length, partly granule-filled with clear, conical tips, and which are waved actively without then being retracted, he (Bovee 1953, 1970) placed in the genus Oscillosignum. Those otherwise like Oscillosignum that form an awl-shaped, rapid, locomotive state with a clear, conical, pseudopodial tip, Bovee (1953, 1970) placed in the genus Subulamoeba. These generic distinctions, although arbitrary, are clearly visible and are useful to distinguish such amebas, and are in keeping with the general trend of classifying naked, lobose amebas on the form and movement of their pseudopods, as expressed in the more or recent systematics of amebas. (ref. ID; 4688)

[ref. ID; 7757]
The genus Vexillifera Schaeffer, 1926 includes fresh and salt water amoebae, which according to Page (Page 1969; Page 1979), produce differently shaped pseudopods from an anterior hyaline zone. Up to now, seventeen species have been described in this genus. Eleven of them, V. bacillipedes (Page, 1969), V. lemani (Page, 1976), and the nine new species recently described by Bovee (1985), are freshwater species, V. telmathalassa (Bovee, 1956), V. armata (Page, 1979), V. browni (Sawyer, 1975), V. minutissima (Bovee and Sawyer, 1979), and V. pagei (Sawyer, 1975), inhabit sea waters. V. pagei was redescribes by Page (Page 1979) as Pseudoparamoeba pagei. Of all these species, only V. bacillipedes is considered as amphizonic according to the reports of Ghitino et al. (1977) and Sawyer et al. (1978). Page (1979) has emphasized the importance that cell surface ultrastructure may have in the taxonomical ordering of the different genera and species of Gymnamoebia. (ref. ID; 7757)

Vexillifera ambulacralis (Penard, 1890) (ref. ID; 3687) reported year? (ref. ID; 3497, 5624)
Vexillifera anapes Bovee, 1985 (ref. ID; 4688 original paper)
Vexillifera arionoides Bovee, 1985 (ref. ID; 4688 original paper)
Vexillifera armata Page, 1979 (ref. ID; 2092 original paper, 2093, 3719) reported author and year? (ref. ID; 7305)
Vexillifera aurea Schaeffer, 1926 (ref. ID; 3687) reported author and year? (ref. ID; 7305)
Vexillifera bacillipedes Page, 1969 (ref. ID; 2092, 2093, 3719, 4667, 6789, 7540)
Vexillifera browni Sawyer, 1975 (ref. ID; 2093, 7757) reported year? (ref. ID; 3847) reported author and year? (ref. ID; 7305)
Vexillifera dadayi Lepsi, 1960 (ref. ID; 3687 original paper)
Vexillifera displacata Bovee, 1985 (ref. ID; 4688 original paper)
Vexillifera filopodia Bovee, 1985 (ref. ID; 4688 original paper)
Vexillifera granatensis M.L. Mascaro, Osuna & C. Mascaro, 1985 (ref. ID; 7757 original paper)
Vexillifera lemani Page, 1976 (ref. ID; 7540, 7757)
Syn; Amoeba ambulacralis Penard, 1920 (ref. ID; 7540)
Vexillifera minuta Bovee, 1985 (ref. ID; 4688 original paper)
Vexillifera minutissima Bovee & Sawyer, 1979 (ref. ID; 7710, 7757) reported year? (ref. ID; 3847) reported author and year? (ref. ID; 6789, 7305)
Vexillifera ottoi Sawyer (ref. ID; 3847) reported author and year? (ref. ID; 2093, 7305)
Vexillifera pagei Sawyer, 1975 (ref. ID; 2093, 7757)
See; Pseudoparamoeba pagei (ref. ID; 7757)
Vexillifera spinoa Bovee, 1985 (ref. ID; 4688 original paper)
Vexillifera subula Bovee, 1985 (ref. ID; 4688 original paper)
Vexillifera telma Bovee, 1985 (ref. ID; 4688 original paper)
Vexillifera telmathalassa (ref. ID; 7305)
Vexillifera telmathalassa Bovee, 1956 (ref. ID; 2092, 7757)
Vexillifera telmathalassa Page, 1972 (ref. ID; 2093)
Vexillifera variabilis Bovee, 1985 (ref. ID; 4688 original paper)

Vexillifera ambulacralis (Penard, 1890) (ref. ID; 3687) reported year? (ref. ID; 3497, 5624)

Descriptions

The granular body possesses several slender pseudopodia stretching forwards and typically few uroids. The nucleus is rather small and contractile vacuoles often appear. (ref. ID; 3497)

Measurements

Length without pseudopodia 10-38 um. (ref. ID; 3497)

Vexillifera anapes Bovee, 1985 (ref. ID; 4688 original paper)

Descriptions

Size and Shape: At rest on substrate, spherical to subglobular to irregular 6.5 to 8.7 um diameter, spherical state 6.5 to 7 um diameter; afloat, radiate with 8 slender pseudopods, body-mass 6.3 to 6.8 um diameter; active, non-locomotive from irregular, 12 to 16 um across, changing shape frequently, with several clear marginal and several slender pseudopods from the dorsal body-surface; in locomotion, spatulate to triangulate 16 to 20 um by 12 to 14 um with clear anterior margin from which 2 or 3 pairs of clear conical, round-tipped pseudopods extend, connected, arc-wise, by parts of the clear anterior margin, with one to three slender pseudopods from the body surface, general shape resembling a duck's foot. (ref. ID; 4688)
Pseudopods: Those of the radiate, floating state, rigid while the ameba floats, are clear, conical, about 1.5 um diameter basally, tapered to barely resolvable tips about 0.25 um diameter, 21 to 25 um long, but during descent to the substrate they crinkle at the bases, oscillate briefly, then twist, coil and retract, replaced briefly by others as the ameba begins movement and locomotion; during locomotion, formed as alternate pairs, to left, then right, clear, conical, round-tipped, extended from a narrow, clear anterior border (3 to 5 um) to lengths of 6 to 8 um, basal diameter about 2.5 um, tapered to about 1.0 um at the rounded tips, connected by an arc of the clear anterior border; there being also extended upward from the body surface during locomotion one to three of the slender pseudopods of the type formed by the radiate state which bend and oscillate at the base, then are retracted, coiling and twisting slowly as they collapse, often replaced by new ones. (ref. ID; 4688)
Rate of Locomotion: Travels 19 to 33 um/min along a slightly sinuous path in steady progress. (ref. ID; 4688)
Uroid: None formed; old locomotor pseudopods being retracted at the rear may resemble uroidal filaments, briefly. (ref. ID; 4688)
Ectoplasm: Thin, clear, delicate, composing the pseudopods and clear peripheral bulges of the active, non-locomotive state and the clear anterior margin of the locomotive state. (ref. ID; 4688)
Endoplasm: Clear, viscous, finely granular. (ref. ID; 4688)
Crystals: About 10 small, flake-like crystals, appearing square, perhaps deeply truncated bipyramids, about 1.25 to 1.5 um across, about 0.25 um thick, usually clustered near the nucleus. (ref. ID; 4688)
Nucleus: Single, spherical, vesicular, about 2.0 um diameter, with a round, central endosome about 1.25 um diameter, pale, difficult to see even with phase contrast, usually about centrally placed in the granular body-mass. (ref. ID; 4688)
Water-expelling Vesicle: Single, spherical, 2 to 3 um diameter at expulsion, elastic and deformed by cytoplasmic pressures during locomotion, expels dorsolaterally near the rear; replaced by a new one formed by the fusion of several smaller vesicles, about 0.5 um diameter, in about 5 min, maintained 6 to 10 min longer before expulsion; another one may be in formation before the previous one expels. (ref. ID; 4688)
Food Vesicles: Not more than one or two present at a time; about 2.0 um diameter; enclose small bacteria in various states of digestion; expelled from dorso-lateral surface near rear end during locomotion. (ref. ID; 4688)
Cysts: Not seen. (ref. ID; 4688)

Etymology

It is named for its appearance in moderate locomotion, when it resembles the splayed, webbed foot of a duck. (ref. ID; 4688)

Habitat

Slow-flowing, cool, freshwater streams at muddy bottom. (ref. ID; 4688)

Type locality

; This vexilliferan was first found in a collection taken in October 1961, from the muddy bottom, at a water temperature of 21 degrees C, of a creek at the crossing of state highway 235, 2.5 mi S of state highway 100, 7.2 mi N of the town of Brooker, Florida, U.S.A. It appears to be widely distributed in small streams on muddy bottom. (ref. ID; 4688)

Vexillifera arionoides Bovee, 1985 (ref. ID; 4688 original paper)

Descriptions

Size and Shape: Spherical to subglobular when at rest on substrate, 7 to 9 um diameter; body mass spherical 6.5 to 8.5 um diameter when afloat, with 3 to 6 (usually 6) pseudopods regularly radiate from the body-mass; in slow movement on substrate, irregular with two or several pseudopods from the body-mass, changing shape continually until locomotion begins, mean size 21 um across; in intermittent locomotion, elongate and limaciform 26 to 54 um long by 8 to 20 um wide with pseudopods formed in pairs at the clear advancing margin and from the bodymass; in steady locomotion, limaciform, 22 to 38 um long (excluding pseudopods) by 6 to 9 um wide, mean 29 by 7 um, l/w ratio 4.3, with a pair of pseudopods at the anterior end of the advancing body, and none to several (usually 2 or 3) from the anterior surface of the granular body-mass. (ref. ID; 4688)
Pseudopods: These are clear, conical round-tipped. Those of the radiate floating state are rigid, 7 to 10 um long, about 8 um diameter basally, tapered to about 0.2 um at the rounded tips; those of a temporary, erect state taken intermittently while locomotive are formed in pairs at approximately right angles to one another from the upper end of the erect body-mass, 5 to 9 um long, 0.8 to 1.0 um diameter basally, tapered to about 0.25 um diameter at the rounded tips; those formed in locomotion from the clear, advancing end are paired, each of a pair at nearly right angles or slightly obtuse ones (84 to 107 degrees) to the other, are dropped to the substrate and overridden by a clear bulge from which the next pair is formed, the formation of pairs alternating left, then right, in steady progress; those from the body surface in locomotion, none to four (usually one or two) being present, are 5 to 13 um long, about 1.0 um diameter, basally, tapered to about 0.2 um at the rounded tips, swung at the bases prior to retraction, then twisting and collapsing while being retracted. (ref. ID; 4688)
Rate of Locomotion: Steady locomotion proceeds over a sinuous path, 20 to 30 um/min, mean rate 26 um on a glass surface. Rapid bursts of advance involve extension of several bursts of clear ectoplasm, one after another, over a distance of about 50 um in 50 to 70 sec, with the body-mass then being drawn along, "inchworm" fashion, before the next series of ectoplasmic bursts occurs, net rate of advance being about the same as the usual rate of locomotion. The slender, oscillating pseudopodia are more often found during the locomotive "bursts", than during the steady rate of progress. (ref. ID; 4688)
Uroid: None is formed. (ref. ID; 4688)
Ectoplasm: Thin, delicate, clear over the body-mass; forms the anterior 1/4 to 1/2 of the length and the pseudopods during locomotion. (ref. ID; 4688)
Endoplasm: Clear, viscous, finely granular. (ref. ID; 4688)
Crystals: Few (seldom more than 10), truncated bipyramids about 1.0 um long, many other crystalline granules, smaller, of undetermined shapes. (ref. ID; 4688)
Nucleus: Single, spherical, vesicular, 2.5 to 3 um diameter, slightly elastic, with distinct central, spherical endosome, 1.3 to 1.8 um diameter, centrally placed in the radiate state, about midway in the granular body-mass during locomotion. (ref. ID; 4688)
Water-expelling Vesicle: Single, spherical, 3 to 4 um diameter at expulsion, replaced by a new one; excentric in the floating state, near the rear in locomotion; forms slowly (in about 5 min) maintained full for 12 to 20 min before expulsion; a second may be forming before the previous one is expelled, dorsolaterally. (ref. ID; 4688)
Food-vesicles: Few (one or 2 usually present) containing small bacteria or remnants thereof, 2 to 3 um diameter; formed at the lower surface of the granular body mass; residue expelled dorsolaterally near the WEV-site. (ref. ID; 4688)
Cysts: Not seen. (ref. ID; 4688)

Habitat

Backwaters of organically laden cool streams, with much decaying vegetal detritus. (ref. ID; 4688)

Type locality

In collections at 19 degrees a quiet backwater of the Suwanee River 1/4 mi above the influx of the White Sulfur Spring into that river near the town of Fort White, Florida, U.S.A. in March 1958. (ref. ID; 4688)

Vexillifera ambulacralis (Penard, 1890) (ref. ID; 3687) reported year? (ref. ID; 3497)

Descriptions

The granular body possesses several slender pseudopodia stretching forwards and typically few uroids. The nucleus is rather small and contractile vacuoles often appear. (ref. ID; 3497)

Measurements

Length without pseudopodia 10-38 um. (ref. ID; 3497)

Vexillifera armata Page, 1979 (ref. ID; 2092 original paper, 2093, 3719) reported author and year? (ref. ID; 7305)

Diagnosis

Locomotive form longer than broad, producing linear or finely conical pseudopodia characteristic of genus from anterior hyaloplasm; length not including long pseudopodia approximately 10 to 23 um, mean 15.5 um; length : breadth ratio 1.0 to 2.2, mean 1.6. The hyaline zone usually occupied about one quarter of the total length. Floating form usually irregularly rounded, with hyaline pseudopodia, if any, usually unevenly distributed. Nucleus 2.8 to 4.2 um, with central nucleolus 1.9 to 2.8 um; nuclear division with dissolution of nuclear membrane by metaphase. Surface covered with flexible hexagonal cylinders (glycostyles), approximately 60-70 nm tall and 50 nm in diameter, unique to genus but not to species. Several trichocyst-like bodies, approximately 5 um long and 0.2 um in diameter, with quadrilateral transverse section, present in each cell; no fixed position; ejection not known to occur. (ref. ID; 2092)

Descriptions

This strain have a spiny appearance, usually longer than broad, with the anterior hyaline region more or less flattened and the posterior mass granular and often conical toward the tail. The pseudopodia start as blunt projections of the hyaline zone, elongate rapidly and become thinner and more or less linear, with a more or less constant diameter along much of the length. After the initial blunt, conical projection has lengthened, the pseudopodium has a basal diameter of less than 0.5 um. When it has reached its full length, often greater than the length of the main cell mass, the pseudopodium may bend, rarely may become helical, and usually is carried back along the sides to be resorbed posteriorly; this accounts for the spiny appearance of the amoeba. The cell moves by advance of the broad hyaline lobe from which the sub-pseudopodia are produced. This lobe may narrow as it is pushed forward, so that the cell as a whole sometimes is urn-shaped, but generally the hyaline is more flattened than the posterior mass. Surface covered with flexible hexagonal cylinders (glycostyles), approximately 60-70 nm tall and 50 nm in diameter, unique to genus but not to species. The amoebae often fed by ingesting one or more bacteria toward the posterior end; ingestion of single bacteria by the hyaline anterior edge was also observed. Large numbers of bacteria are not ingested in a single food vacuole. Ten amoebae bore from four to 12 sub-pseudopodia, including those along the sides and at the posterior end, with a mean count of more than seven. Again, this maximum probably can be surpassed. The locomotive rates of 10 amoebae at 19 degrees were 8.4 to 17 um per minute, that is, from 0.6 to 1.1 times their lengths. No crystalline or other dense granules were observed, and no contractile vacuole was present. Nuclear division with dissolution of nuclear membrane by metaphase. Several rod-shaped trichocyst-like bodies (TLB's), approximately 5 um long and 0.2 um in diameter, were recognized with the light microscope only after having been discovered in sections. They could be observed in living cells even with bright-field optics, more distinctly in somewhat flattened cells with phase contrast. They were also seen in wet mounts fixed by addition of saturated mercuric chloride solution and in hematoxyin preparations. (ref. ID; 2092)

Cyst: No cysts were ever seen. (ref. ID; 2092)

Marine species. (ref. ID; 2093)
V. armata was observed to have a surface coat only 70 nm thick, including a layer of hexagonal cylinders (glycostyles). (ref. ID; 3719)

Type locality

Kingsbridge Estuary, South Devon, England. (ref. ID; 2092)

Type material

Type slides have been deposited in the British Museum (Natural History) and given the numbers 1978:6:28:1 (holotype) and 1978:6:28:2 (paratype). (ref. ID; 2092)

Measurements

In locomotion on the under side of a coverslip, 100 amoebae were from 10 to 23 um long, with a mean of 15.5 um (these lengths do not include the long pseudopodia). The length : breadth ratio was from 1.0 to 2.2, with a mean 1.6. The hyaline zone usually occupied ?about one water of the total length. In 20 amoebae, the length of the longest pseudopodium ranged from 0.2 to 1.1 times of the main cell mass, though it undoubtedly can become greater. Floating form usually irregularly rounded, with hyaline pseudopodia, if any, usually unevenly distributed. Nucleus 2.8 to 4.2 um, with central nucleolus 1.9 to 2.8 um. (ref. ID; 2092)

Vexillifera bacillipedes Page, 1969 (ref. ID; 2092, 2093, 3719, 4667, 6789, 7540)

Descriptions

This species has only a thin, amorphous glycocalyx with no glycostyles. (ref. ID; 2092)
Freshwater species. (ref. ID; 2093)
V. bacillipedes possesses irregular tufts extending from the glycocalyx. (ref. ID; 3719)

Vexillifera browni Sawyer, 1975 (ref. ID; 2093, 7757) reported year? (ref. ID; 3847) reported author and year? (ref. ID; 7305)

Descriptions

Marine amoebae. (ref. ID; 3847)

Vexillifera displacata Bovee, 1985 (ref. ID; 4688 original paper)

Descriptions

Size and Shape: At rest, spherical 7 to 8 um diameter; afloat, when disturbed from the active locomotive state, irregularly radiate from an ovate body-mass about 8 um long by 5 um wide; active, but non-locomotive, body mass ovate 8 to 10 um long by 5 to 7 um wide, with several pairs of pseudopods peripherally extended from a clear basal bulge for each pair; in locomotion, body-mass ovate, 7 to 12 um long by 6 to 8 um wide, with 2 to 4 similar pairs of pseudopods from bulges at the advancing end, or the body surface. (ref. ID; 4688)
Pseudopods: These are clear, slender, tapered and originate, usually, as a pair, occasionally as a singlet, arising from a clear bulge at the periphery, from the body surface, or the anterior end; each bulge is 2 to 5 um diameter, sometimes extended as a short, rounded cone. Each pseudopods arising from the cone has a basal diameter of about 1.0 um, and tapers to an indistinct tip less than 0.2 um diameter; pseudopodal length varies from 5 to 12 um, those of a pair being about the same length, singlets usually being somewhat longer than those of pairs. During retraction, they bend at their bases, swing upwards, then collapse into the basal cone, which is, shortly after, also retracted. (ref. ID; 4688)
Rate of Locomotion: Usually between 12 to 15 um/min, with occasional spurts of more rapid progress to 20 um/min, mean rate 14.2 um/min. (ref. ID; 4688)
Uroid: None is formed; a few, old retracting pseudopods may temporarily trail before retraction, especially if the ameba has just altered course. (ref. ID; 4688)
Ectoplasm: Thin, clear, viscous, composes the clear bulges and the pseudopods. (ref. ID; 4688)
Endoplasm: Clear, viscous, finely granular. (ref. ID; 4688)
Crystals: Several, about 0.3 um, shape not clearly determined. (ref. ID; 4688)
Nucleus: Single, spherical, vesicular, about 3.3 um diameter, with central endosome about 2 um diameter; both difficult to discern even with phase contrast; usually centrally placed in the granular body-mass. (ref. ID; 4688)
Water-expelling Vesicle: Single, spherical, formed near the nucleus, slowly (in about 5 min), maintained 10 to 15 min before expulsion, usually laterally near the rear; replaced by a new one. (ref. ID; 4688)
Cysts: Not seen. (ref. ID; 4688)

Comments

V. displacata somewhat superficially resembles V. browni Sawyer, 1975, but the latter is clearly marine and unable to survive in freshwater (Sawyer 1975) whereas V. displacata is a freshwater species and its pseudopods are more nearly filose than those of V. browni as the latter appear in Sawyer (l.c.) photomicrographs. (ref. ID; 4688)

Habitat

Slow-flowing streams on muddy bottom. (ref. ID; 4688)

Type locality

This ameba was first found on muddy bottom of a drainage ditch at a water temperature of 22.5 degrees C in November, 1961, on the southern outskirts of the city of Gainesville, Florida, U.S.A. It apparently is widely distributed. (ref. ID; 4688)

Vexillifera filopodia Bovee, 1985 (ref. ID; 4688 original paper)

Descriptions

It is widely distributed in quiet pools and backwaters with much organic debris. (ref. ID; 4688)

Size and Shape: Spherical to slightly subspherical when at rest on substrate, 7 to 8 um diameter; body-mass of the floating state also spherical with 6 to 8 long slender pseudopods; when active but not locomotive on substrate, subglobular, 8 to 12 um diameter with one to several long, slender pseudopods; when locomotive, granular body-mass subglobular, 10 to 12 um diameter, to trapezoidal, 12 to 16 um across at widest point, with anterior clear margin 15 to 18 um broad and 6 to 8 um long; with long, slender pseudopods extended from the leading edge of the clear margin and/or from the body-mass. (ref. ID; 4688)
Pseudopods: These are long, slender, tapered, nearly filiform, extended from a clear basal cone at the body surface that is 1.5 to 3.5 um diameter basally and about 5.0 um or less where the base of the filiform pseudopod begins, the filiform portion extending to lengths of 30 um, barely visible at the tips, on the locomotive state, and to lengths of 52 um for the radiate, floating state. One or more of them are usually in oscillatory motion, swung from their bases preparatory to retraction, as newer ones form, the older, oscillating ones retracting by collapsing in spiral coils onto the body-mass or onto the clear advancing margin as the newer ones are extended. (ref. ID; 4688)
Rate of locomotion: This ameba moves on the glass surface at 16 to 24 um/min when in steady progress, with occasional rapid advance up to 48 to 52 um/min under bright illumination. (ref. ID; 4688)
Uroid: None is formed by this species; occasionally a few, trailing pseudopods in the process of retraction may temporarily resemble twisted uroidal filaments. (ref. ID; 4688)
Ectoplasm: Thin, clear over the body-mass; composes the clear anterior part in locomotion and the pseudopods. (ref. ID; 4688)
Endoplasm: Clear, viscous, finely granular. (ref. ID; 4688)
Crystals: Usually 10 to 20 present; about 0.3 to 1.0 um in size, exact shape and number of faces not determined. (ref. ID; 4688)
Nucleus: Single, spherical, pale, difficult to distinguish, 2.5 um diameter with central, spherical endosome about 1.0 um diameter, or slightly less. (ref. ID; 4688)
Water-expelling Vesicle: Single spherical, excentric in the floating state, near the rear end in locomotion, 2.5 to 3.2 um at expulsion, replaced by a newly formed one; forms quickly in 3 to 5s, maintained 4 to 8s before expulsion. (ref. ID; 4688)
Food vesicles: One or two usually present, containing bacteria or residues thereof; formed beneath the body-mass, expelled dorso-laterally. (ref. ID; 4688)
Cysts: None were observed. (ref. ID; 4688)

Habitat

Quiet, swampy backwaters of ponds, lakes, streams, at 18 to 25 degrees C. (ref. ID; 4688)

Type locality

This ameba was first seen in November 1949 from an old water sample that was collected on June, 116, 1948, from a stagnant freshwater canal extending from West Okoboji Lake at crescent Beach, in Dickinson Country, Iowa, U.S.A. (ref. ID; 4688)

Vexillifera granatensis M.L. Mascaro, Osuna & C. Mascaro, 1985 (ref. ID; 7757 original paper)

Descriptions

Light microscopy: The amoebae rapidly became motionless and acquired a rounded shape when placed between the microscope slide and the cover slip. In hanging drops, displacement is slow and occurs from an anterior ectoplasmic zone. Most amoebae in motion display different sized pseudopods up to 25 um long and therefore show a spiny appearance. Floating forms appear when cultures are resuspended in a liquid medium. Morphologically these are similar to the floating forms of the genus Vannella, that is, they are composed of a central rounded endoplasmic mass with tapering radiate pseudopodia. The number of pseudopods can be up to 9. A clear difference exists between ecto- and endoplasm. The latter is extremely granulated, and a variable number of refractile crystalline inclusions may be observed in it inside. When the trophozoites adhere tightly to the substrate, these crystals are clearly visible and can number 7-20 per amoeba. This inclusions are quadrangular or rectangular truncated bipyramids and its normal sizes are between 0.5 and 1 um. Most amoebae show only one pulsatile vacuole, usually in a posterior position with regard to the ectoplasm. The size of the amoebae is in the range 10-15 um long by 4-13 um wide, excluding the pseudopods. The nucleus is single in most specimens and includes a nuclear membrane, only one nucleolus, which is central and varies in shape, and a clear nucleoplasm. A similar morphology of the nucleus has been visualized after staining with Gallocianine. The diameter varies from 3 to 6 um. As cultures are progressively dessicated, the amoebae retract, stop moving and give rise to round or oval forms with a major diameter of 10-20 um. (ref. ID; 7757)
Transmission electron microscopy: The amoebae have a lobulate shape, due to pseudopodial projections. A clear difference between ecto- and endoplasm cannot be observed. The plasma membrane consists of two electrondense layers. With increased magnification, the outer electron-dense layer of the plasma membrane appeared somewhat thicker than the inner one. On the outer one there are electron-dense elements distributed uniformly over the entire surface of the amoeba, including the pseudopodial projections. These glycostyles rise about 150 nm above the plasma membrane, looking like a T, as tall as wide. Its section is not hexagonal like in V. armata (Page 1979). The glycostyles are absent in the food vacuoles and their possible association with phagocytic processes cannot be deduced or excluded as a consequence of these observations. The cytoplasm is very rich in free ribosomes. The rough endoplasmic reticulum is poorly developed. Small vesicles surrounded by ribosomes are present. A structure equal or similar to the Golgi body does not exist. The few mitochondria observed are oval or elongated in shape, and with a very electron dense matrix. The cristae are tubular and anastomose. No dense intramitochondrial bodies are evident. The food vacuoles contain generally one only phagocytized bacterium. Cytoplasmic filaments and microtubules were not seen. Intracytoplamic crystalline inclusions disappear during the processing for electron microscope observations, giving rise to empty lacunar spaces in the cytoplasm. The nucleus occurs in different positions and is a typical vesicular nucleus. The nuclear envelope consists of two membranes, which is a wide perinuclear space, with ribosomes adherent to the external membrane. The nucleoplasm is finely granular. The nucleolus, always single and in a central position, consists mainly of "pars granular". This species does not survive in lungs of albino mice after intranasal inoculation. (ref. ID; 7757)

Notes

The species described may be included in the genus Vexillifera, according to the generic characters indicated by Page (1969). The light microscopical study has revealed the existence in the cytoplasm of clear crystalline inclusion, which are currently under investigation in this laboratory after isolation by lysis of the trophozoites. Although Page did not mention the existence of this type of inclusions in V. bacillipedes, their presence is suggested by the photographs is his paper (Page 1979). Eight of the nine species recently described by Bovee (1985) have crystalline inclusions, in different forms and sizes, but none are so clear and patent as the inclusions observed in this species. In Bovee's work (1985), the drawings and descriptions do not give us the possibility of securing a clear morphological similitude between his species and ours, on the other hand, having not published any ulrastructural study we cannot compare it. V. armata, the other species of this genus studied with the electron microscope lacks crystalline inclusions and any other type of dense granules. Pulsatile vacuoles are also absent in this marine species. Mitochondria of V. armata (Page 1979) are very similar to those of the species described in the present paper in both the appearance of the cristae and electrondensity. The absence of a Golgi body or some similar membrane system differentiates this species clearly from V. armata or V. bacillipedes which both have a Golgi body close to the nuclear region (Page 1979). Nevertheless, the most remarkable characteristic is the peculiar morphology of its cell surface. While V. bacillipedes presents an amorphous glycocalyx without glycostyles though with long and irregular prolongation (Page 1979), this species possesses a very characteristic glycocalyx with a special morphology and disposition. This type of glycocalyx, with glycostyles arranged in a regular manner, differs clearly from that of V. armata (Page 1979) and from those of the species of the Vannella genus previously ultrastructurally described (Page 1979). Glycostyles of Pseudoparamoeba pagei are also distinct (Page 1979). All these considerations have lead us to believe that we are describing a new species and, previously to a general reorganization of the taxons of the suborder Conopodina, which possibly will be accomplished in a few years time by experts in this subject, we include it in the genus Vexillifera Schaeffer, 1926, and propose the specific denomination of Vexillifera granatensis. (ref. ID; 7757)

Vexillifera lemani Page, 1976 (ref. ID; 7540, 7757)

Synonym

Amoeba ambulacralis Penard, 1920 (ref. ID; 7540)

Description

Freshwater species. (ref. ID; 7757)

Vexillifera minuta Bovee, 1985 (ref. ID; 4688 original paper)

Descriptions

Size and Shape: At rest on substrate, spherical to subglobular, 5 to 6 um diameter, sometimes with one to three long, slender pseudopods from the upper surface; afloat, body spherical with 6 long, slender, radiate, clear pseudopods; in slow, non-locomotive movement, body-mass subglobular or irregular, 6 to 8 um across, with one to several long, slender pseudopods; in locomotion, 13.5 to 17.8 um long by 5 to 8.3 um wide, mean 15.3 by 6.2 um, length/breadth ratio 2.5, with pseudopods anteriorly and from body surface. (ref. ID; 4688)
Pseudopods: Those of floating state (usually 6) are clear, regularly radiate, 18 to 26 um long, about 1.0 um basally, tapered to about 0.2 um, barely resolvable, at the tips; of the active, non-locomotive state, similar pseudopods, 6 to 18 um long, from a clear, hemispherical, peripheral bulge, singly or in pairs, oscillating basally before retraction; in locomotion, in pairs from a clear, flat anterior border, overridden by extension of a semicircular bulge (about 5.5 um diameter) from which another pair of slender pseudopods protrude forward to lengths of 6 to 8 um, and pseudopods from the body surface, 5 to 18 um long, that oscillate from the base prior to retraction, as many as 1 to 4 pairs from the anterior margin and 1 to 3 pairs laterally and one or more, usually in pairs, from the dorsal body surface being present at one time, or as few as one forming pair at the anterior margin and a single oscillating one from the body surface. (ref. ID; 4688)
Rate of Locomotion: 11 to 24 um/min, mean rate 19 um/min in steady progress. (ref. ID; 4688)
Uroid: None occurs, but the posterior end, during steady locomotion, is often temporarily a rounded, clear bulb. (ref. ID; 4688)
Ectoplasm: Thin, pale, composes the surface of the globular body-mass, the clear bulges and borders from which pseudopods extend and the pseudopods. (ref. ID; 4688)
Endoplasm: Clear, viscid, finely granular. (ref. ID; 4688)
Crystals: Few (4 to 10), about 0.3 to 0.75 um long, number of faces difficult to determine. (ref. ID; 4688)
Nucleus: Single, spherical, vesicular, 2.3 um diameter (with distinct endosome 1.2 um diameter) usually centrally placed in the granular body-mass. (ref. ID; 4688)
Water-expelling Vesicle: Excentric in the floating stage, about 3.0 um diameter at expulsion at the rear of the granular body-mass during locomotion. (ref. ID; 4688)
Food Vesicles: Small, 2 to 3.5 um diameter, only 1 or two present at any one time, contain bacteria or residues thereof, expelled dorso-laterally near WEV. (ref. ID; 4688)
Cysts: Not seen. (ref. ID; 4688)

Habitat

In decaying vegetation in warm shallow waters at the edge of lakes with sandy bottoms. (ref. ID; 4688)

Type locality

This ameba was found repeatedly in collections from shallow water on the west side of Newnan's Lake on the eastern border of the city of Gainesville, Florida, U.S.A., from August 1956 through June 1962. (ref. ID; 4688)

Vexillifera minutissima Bovee & Sawyer (ref. ID; 3847) reported author and year? (ref. ID; 6789, 7305)

Descriptions

Marine amoebae. (ref. ID; 3847)

Vexillifera ottoi Sawyer, 1979 (ref. ID; 7710, 7757) reported year? (ref. ID; 3847) reported author and year? (ref. ID; 2093, 7305)

Descriptions

Marine amoebae. (ref. ID; 3847)

Vexillifera spinoa Bovee, 1985 (ref. ID; 4688 original paper)

Descriptions

Size and Shape: At rest on substrate, irregularly subglobular with wrinkled surface, 15 to 17 um diameter; afloat, radiate, body-mass spherical, 11 to 13 um diameter with 8 straight to slightly curved pseudopods; when active, but non-locomotive, irregular, 26 to 37 um across with several pairs of pseudopods extended from clear bulges of the periphery; when moderately locomotive, body-mass ovate with one to thee pairs of pseudopods, each from an anterior, clear bulge; fan-shaped in rapid advance with several pairs of pseudopods formed from clear bulges that coalesce as a clear, anterior-lateral border. (ref. ID; 4688)
Pseudopods: Those of the floating state are 17 to 21 um long with a clear, basal cone 3 um diameter, extended about 6 um, from which a slender, tapered pseudopod of about 1.0 um basal diameter extends the remainder of the length to a barely resolvable tip about 0.25 um diameter; those of these active and locomotive state originate in pairs, each pair from a clear subglobular bulge at the lateral or dorsal surface or the advancing end, the clear bulge being 4 to 7 um diameter, each pseudopod of the pair being 6 to 12 um long, about 0.6 um diameter basally, and less than 0.2 um diameter at the tip, which is indistinct; these are diverted laterally in locomotion, where they bend at the bases, oscillate, coil and collapse and retract into the clear bulge, which also collapses. (ref. ID; 4688)
Rate of Locomotion: Slow, sluggish, 5 to 12 um/min in the ovate form, 8 to 22 um/min in the fan-shaped form, along a wavy path. (ref. ID; 4688)
Uroid: None formed; an occasional filament may trail from the posterior margin of the fan-shaped state during locomotion. (ref. ID; 4688)
Ectoplasm: Thin, clear, viscous; composes the clear bulges, pseudopods and clear anterior margin of the locomotive state. (ref. ID; 4688)
Endoplasm: Clear, viscous, finely granular. (ref. ID; 4688)
Crystals: None; but several glossy amorphous granules may be present in the cytoplasm. (ref. ID; 4688)
Nucleus: Single, spherical, vesicular, pale, difficult to discern even with phase-contrast microscopy, 4.5 um diameter, with central endosome about 3 um diameter, nucleus usually close to center of the granular body-mass. (ref. ID; 4688)
Water-expelling Vesicle: None present. (ref. ID; 4688)
Food Vesicles: One to several usually present, 2 to 3 um diameter containing bacteria in various states of digestion, expelled dorso-laterally. (ref. ID; 4688)
Cysts: Not seen. (ref. ID; 4688)

Habitat

Brackish backwaters of the mouths of rivers at cool temperature. (ref. ID; 4688)

Type locality

This ameba was numerous in a collection at a water temperature of 14 degrees C from a brackish backwater of the Peace River at Punta Gorda, Florida, U.S.A., in January 1959, near the influx of the river into the Gulf of Mexico. (ref. ID; 4688)

Vexillifera subula Bovee, 1985 (ref. ID; 4688 original paper)

Descriptions

Size and Shape: At rest on substrate, spherical, 5 to 6 um diameter; afloat, body-mass spherical, about 3 um diameter, with 4 radiate pseudopods; in non-locomotive activity, body-mass globular to irregular, 5 to 7.5 um across with one or two pseudopods from the body surface and one to 3 pairs at the periphery; in locomotion, spatulate, 14 to 20 um long by 6 to 8 um wide, mean 17x7.5 um, body-mass at the rear, ovoid, or body awl-shaped 18 to 36 um long, 3.5 to 4.5 um broad, mean 26.3 by 4.1 um, length/width ratio 6.2, with granular body-mass posterior. (ref. ID; 4688)
Pseudopods: Those of the radiate state are clear, conical, 4 to 6 um long, about 1.3 um diameter basally, tapered to about 0.3 um diameter, apically; those of active and locomotor state from the periphery or advancing margin are clear, conical, 4 to 16 um long, 0.8 to 1.3 um diameter, basally, tapered to about 0.25 um diameter at the rounded apices, often with irregular flow of narrow ectoplasm along the inner edge of the leading pseudopod; older ones bend at bases, lift, elongate to about 25 um long, twist spirally and retract laterally. (ref. ID; 4688)
Rate of Locomotion: In steady locomotion, 26 to 34 um/min, mean 30.3 um/min, with occasional short, rapid bursts up to 37 um/min. (ref. ID; 4688)
Uroid: None. (ref. ID; 4688)
Ectoplasm: Thin, clear; forms pseudopods and their connecting clear waves where such occur. (ref. ID; 4688)
Endoplasm: Clear, viscous, finely granular. (ref. ID; 4688)
Crystals: Usually 3 to 6 highly refractile crystals 0.5 to 1.0 um long, number of faces not clearly distinguishable. (ref. ID; 4688)
Nucleus: Single, vesicular, spherical, extremely pale, difficult to see, even with phase-contrast optics, 2.25 um diameter, with an also indistinct, central endosome about 1.5 um diameter; nucleus usually centrally placed in the granular body-mass. (ref. ID; 4688)
Water-expelling Vesicle: Single, spherical, about 2.5 um diameter at expulsion near the rear end, replaced by a new one formed near the nucleus and transported to the rear one-third of the body; slowly formed, maintained many minutes before expulsion. (ref. ID; 4688)
Food vesicles: Usually only one present at any one time, about 2.5 um diameter, contents undetermined, perhaps small bacteria or miniscule bits of organic matter; expelled dorso-laterally near WEV. (ref. ID; 4688)
Cysts: Not found. (ref. ID; 4688)

Habitat

Cool, slow-flowing streams with little detritus. (ref. ID; 4688)

Type locality

This organism was found in numbers of over 50 individuals in a collection in November 1957 from a freshwater creek 1+1/2 mi NW of Fairbanks, Florida, U.S.A, where State Highway 24 crosses the creek by bridge, at water temperature of 17.8 degrees C. (ref. ID; 4688)

Vexillifera telma Bovee, 1985 (ref. ID; 4688 original paper)

Descriptions

It appears to be widely distributed in well-fertilized, stagnant, freshwater situations. (ref. ID; 4688)

Shape and Size: Irregularly spheroid to subspherical at rest on substrate, 8 to 10 um across; radiate when afloat with numerous clear, conical pseudopods, body-mass spheroid, 6 to 8 um diameter; when active, but not locomotive, subglobular to irregular, 12 to 20 um across with several peripheral pseudopods and several from the body-surface; when locomotive, body-mass 20 to 32 um long by 14 to 26 um wide, mean 25x19 um, with pseudopods extended from the anterior end and the dorsal surface. (ref. ID; 4688)
Pseudopods: These are clear, conical, round-tipped, extended from the periphery and/or the body-surface. Those of the floating, radiate state are 3 to 5 um long, 1.5 um diameter basally, tapered to about 1.0 um diameter at the rounded tips rigid while afloat, but oscillatory and twisting during retraction after descent to the substrate. Pseudopods from the body-surface during locomotion are extended singly, in pairs, or tridents (more frequently the latter) each 3 to 8 um long, 1.5 to 2.2 um diameter basally, tapered to about 1.0 um diameter at the rounded tip. Pseudopods of the locomotive state, extended from the clear, peripheral or anterior margin, are 15 to 25 um long, flattened slightly if against the substrate, about 2 um wide at the bases and 1.5 um wide at the rounded tips. Pseudopods extended forward and upwards from the clear, anterior or peripheral margin or from the body surface oscillate at their bases, then twist during retraction. Those along and adherent to the substrate are retracted at the sides and rear of the body-mass with little or no oscillation. (ref. ID; 4688)
Rate of Locomotion: Usually between 12 and 15 um/min. (ref. ID; 4688)
Uroid: None; no uroidal filaments. (ref. ID; 4688)
Ectoplasm: Clear thin; no visible ridges or structures; composes clear margin and pseudopods. (ref. ID; 4688)
Endoplasm: Clear, viscous, finely granular. (ref. ID; 4688)
Nucleus: Single, vesicular, spherical, 2 or 3 um diameter, with one central, spherical to slightly irregular endosome 1.5 to 1.7 um diameter. (ref. ID; 4688)
Water-expelling Vesicle: Single, spherical, excentric or posterior, 3 to 4.5 um diameter at expulsion in locomotive cells, 4.5 to 6.2 um diameter in floaters, replaced by a newly formed one; forms slowly; maintained, full, for 15 min in the locomotive state to 60 min or more in the floating state before expulsion. (ref. ID; 4688)
Crystals: Several dozen light-refractile crystalloids of indefinite shapes, 0.75 to 1.25 um long, in the granular endoplasm. (ref. ID; 4688)
Food-vesicles: One or more usually present, 2 to 5 um diameter, containing bacteria or remnants of them; wastes expelled through the latero-dorsal surface at or near the rear. (ref. ID; 4688)
Cysts: None were found. (ref. ID; 4688)

Comments

V. telma somewhat resembles V. bacillipedes Page, 1969, but is somewhat larger (20 to 30 um in locomotion, compared to a mean length of 12.5 um for V. bacillipedes) and has many small distinguishable crystals, whereas V. bacillipedes has none; the water-expelling vesicle of V. telma develops from a single, small vesicle, whereas that of V. bacillipedes forms by fusion of several small vesicles; the "bacilliform" pseudopods reported for V. bacillipedes are not formed by V. telma. (ref. ID; 4688)

Habitat

Stagnant freshwaters with organic detritus at temperatures between 20 and 25 degrees C. (ref. ID; 4688)

Type locality

A waterfilled ditch near a chemical fertilizer plant at El Segundo, California, U.S.A., in February 1950. (ref. ID; 4688)

Vexillifera telmathalassa (ref. ID; 7305)

Descriptions

The spherical nucleus (2-3 um diameter) contains a central nucleolus. The size of sedentary forms is 8-10 um rounded, and radiate floating forms are 6-8 um body size, with pseudopods to 45 um. Locomotive forms are 15-45 um long with pseudopods 5-30 um long, emanating from the margin or body surface. The long tapered subpseudpodia project outward or upward from the leading edge of the amoeba, and characteristically relax and collapse before retraction. The ectoplasm is clear surrounding a finely granular endoplasm. Large vacuoles known as "glanzkorper" occur in the cytoplasm in cultured specimens, and especially visible in the afternoon. Floating forms produce long tapered subpseudopodia that may be bent irregularly. Upon settling, the floating form produces a trident of three pseudopodia attached to the substrate (Bovee 1956; Bovee and Sawyer 1979; Page 1983). (ref. ID; 7305)

Remarks

The glycostyles projecting from the plasma membrane are somewhat unique for a species of Vexillifera. They are more stubby and compactly arranged than in other species (Page 1983). However, they sometimes have a fine filamentous projection extending from the tip as occurs in other species of Vexillifera (Page 1983). The filamentous projections appear to cross-link glycostyles on opposing surfaces of cell, such as between closely spaced pseudopodia. Similar fine filaments cross-linking glycostyles on the inner surface of secretory vesicles. While somewhat unique, the general arrangement and shape of the glycostyles is closer to that of Vexillifera spp. than to other glycocalyx-bearing genera (Page 1983). Since the fine structure data reported here expands the taxonomic indicators for V. telmathalassa, and provides a broader context for identifying it, some key features are summarized in comparison to related species in Table 1. This table provides a concise summary of fine structural and light microscopic features that are presently scattered in the literature. The similarity of the glycocalyx on the plasm membrane and the inner lining of the Golgi vesicles within the cytoplasm suggests that these secretory vesicles supply additional membrane to the surface of the cell by fusion with the plasma membrane and evagination as has been reported for other amoebae, including scale-bearing species (Anderson 1977; Page 1983). Evagination of vesicular membranes after fusion with the plasm membrane of cell typically projects the glycostyles outward. The role of the filamentous observed on the surface of V. telmathalassa requires further investigation. They may provide a surface coat of adhesive webs to better entangle and capture prey particles, and/or by cross-linking closely apposed membrane surface may help to strengthen the interface of the cell with the environment. It is not possible to fully characterize the glycocalyx by routine stained techniques for transmission electron microsopy. (ref. ID; 7305)

Habitats

Marine. (ref. ID; 7305)

Vexillifera variabilis Bovee, 1985 (ref. ID; 4688 original paper)

Descriptions

Size and Shape: At rest on substrate, spherical to subglobular, 6 to 8 um diameter; when afloat, body mass 5 to 6 um diameter with 6 to 8 slender, radiate pseudopods; in locomotion irregular trapezoidal to elongate, 20 to 52 um long by 6 to 10 um wide, 27x8 um, often limaciform, with pseudopodia from an anterior clear margin and from the body-surface; form and numbers of pseudopods and direction of progress changing quickly and frequently during locomotion. (ref. ID; 4688)
Pseudopods: Those of the floating stage are long and slender, 30 to 50 um long, less than 1.0 um diameter basally, tapered to barely resolvable tips about 0.2 um diameter; they extend from clear, bluntly-rounded, short, slightly tapered, a nearly cylindrical bases at the body surface. Pseudopods of the active, non-locomotive state form in conical, round-tipped pairs at the periphery from short, clear, ectoplasmic extensions of a clear wave, pseudopods 3 to 8 um long, 2 to 3 um basal diameter, bulging at the tips where they contact the glass surface; other long, slender ones are formed from the clear border or the body-surface like those of the radiate state, 22 to 58 um long, slightly or in pairs from the short, blunt basal cones; those latter ones swing at their bases before crinkling, coiling and retracting, being quickly replaced by newly extended ones. Pseudopods of the locomotive state are similar, but extend from a clear, anterior margin in pairs, those that contact the glass being lifted and retracted at the rear, those long, slender ones erected into the water being oscillatory at the base prior to retraction. Sometimes one of a pair of pseudopods will contact the glass, the other being erect, oscillatory and retracted. (ref. ID; 4688)
Rate of Locomotion: This is highly variable, since the amebas alter from and direction frequently and rapidly. Where steady advance several times the length of the body occurred, mean rate was 24 um/min. (ref. ID; 4688)
Uroid: None is formed; occasionally a pair of pseudopods retracting at the rear will form a temporary, clear bulge that is quickly absorbed. (ref. ID; 4688)
Ectoplasm: Thin, clear, fluid; forms clear margin and pseudopods. (ref. ID; 4688)
Endoplasm: Clear, viscous, finely granular. (ref. ID; 4688)
Crystals: A new (6 to 17, by counts) crystalloid, light-refracting granules in the endoplasm, less than 1.0 um, shape and number of faces not determined. (ref. ID; 4688)
Nucleus: Single, spherical, vesicular, 3 to 3.5 um diameter, with central, spherical endosome 2 to 2.5 um diameter; central in the body-mass of the floating state, near the anterior of the granular body-mass in locomotion. (ref. ID; 4688)
Water-expelling Vesicle: Excentric, 4 to 5 um diameter at expulsion in the resting and floating state, slowly formed (30 to 50 sec.), maintained 60s or more before expulsion; in locomotive individuals, forms near the rear in locomotion in 12 to 32 sec., maintained 15 to 25 sec. before expulsion dorso-laterally near the rear end, replaced by 1 newly formed in the granular endoplasm. (ref. ID; 4688)
Food Vesicles: Not seen. (ref. ID; 4688)
Cysts: Not seen. (ref. ID; 4688)

Habitat

Clear, quiet freshwater pools with little organic debris, at 20 to 25 degrees C. (ref. ID; 4688)

Type locality

This organism was found first in August 1959, in a rain-water filled pool at 21.5 degrees C on a granite outcrop ("Bald Knob") at the summit of Salt Pond Mountain (altitude 4,250 ft.) in Giles County, Virginia, U.S.A. (ref. ID; 4688)