Synonyms. _Amphileptus fasciola_ Ehr. '38; Dujardin '41; Lachmann
'56; Cohn '66, Diesing '65.
_Loxophyllum fasciola_ Claparède & Lachmann '58;
Balbiani '61.
_Loxophyllum duplostriatum_ Maupas '83. Shevyakov '96.

Body frequently brown or brilliant yellow in color, somewhat sigmoid
in form with tapering anterior end, the extremity of which is turned
dorsally. The proboscis is about half the entire length and is not
sharply marked from the rest of the body but tapers gradually, its
base being equal to the diameter of the body at its middle point. The
body is slightly contractile and the posterior end is carried to a
rounded point, but not into a distinct tail. Unlike the fresh-water
variety, this one has no hyaline margin nor hyaline caudal region,
and the contractile vacuole is double or multiple on the dorsal side
near the posterior end. Cilia are present only on the under (right)
side, with, however, a row of large cilia marking the course of the
elongate mouth, upon its left side. The right side is striated, the
left arched and without markings. The endoplasm is finely granular
with, however, larger food particles in the process of digestion,
while specimens are occasionally seen with the natural form
completely lost through distortion caused by over-large captures (Cf.
also Wrzesniowski '70, p. XXIII, fig. 32). Movement continuous, slow,
and gliding; very little tendency to jerking movements. Macronucleus
double, both parts spherical, and placed in about the center of the
larger part of the body; closely approximated but not, as Schewiakoff
described, connected. In conjugation, a large form unites with a
smaller one, the mouth parts being connected. Details of conjugation
and macronuclei not made out. Length 200µ to 600µ.