Frontonia ocularis Bullington, 1939 from the near-shore benthos of marine estuary Accabonac Harbor. It measures 115 um in length. It is quite distinctive and unusual by virtue of the anterior dark pigment spot similar to those seen in metopids. The paper by Pan et al 2013 solved the identification.
"Improved diagnosis: Marine or brackish Frontonia, about 115–140 × 50–75 μm in vivo, reniform with anterior end broad and posterior end slightly narrowed, right margin depressed in anterior 1/3 of body; length to width ratio about 2:1; small buccal field about 15 to 20% of body length; a prominent pigment on right side of anterior extremity; about 93–107 somatic kineties; three vestibular and three or four postoral kineties; peniculi 1 and 2 each with four rows, peniculus 3 with two rows; macronucleus ellipsoidal, located in central region of body; two contractile vacuoles located right-ventral, one in anterior half and the other in posterior half of body."

Studies on Three Diverse Frontonia Species (Ciliophora, Peniculida), with Brief Notes on 14 Marine or Brackish Congeners.
Xuming PAN, Weiwei LIU, Zhenzhen YI, Xinpeng FAN, Khaled A. S. AL-RASHEID, and Xiaofeng LIN. Acta Protozool. (2013) 52: 35–49 doi:10.4467/16890027AP.13.004.0832

Imaged in Nomarski DIC using Olympus BH2S under SPlan 40x objective plus variable phone cropping on Samsung Galaxy S9+.