Ophryoglena Ehrenberg, 1831 (ref. ID; 2014)
Class Oligohymenophora: Subclass Hymenostomata: Order Hymenostomatida (ref. ID; 2014)

[ref. ID; 2014]
Medium- to large-sized ciliate, oval to pyriform in outline, transparent. The oral aperture is situated in the anterior quarter of the body, and is characteristically the shape of the concha of the right human ear with a small posterior projection similar to the tragus of the ear. The buccal cavity contains an undulating membrane and 3 membranelles which are arranged helically. On the left of the oral aperture there is a refringent body, shaped like a watch glass, often with a pigment spot on its convex side. The spot is green-yellow in life and strains deeply with iron haematoxylin and safranin and its location is used as a character for the identification of the species. The somatic ciliation is dense with many kineties running longitudinally down the body (except on one species where they spiral, Canella and Rocchi-Canella, 1976). There is a definite pre-oral suture. 1 or 2 contractile vacuoles open laterally to the right of the oral aperture. The macronucleus is circular or elliptical in outline, strongly flattened and more or less folded on itself. Careful observation is required not to attribute a sausage or horseshoe shape to the nucleus of the genus.
Quote; Colin R. Curds, Michael A. Gates and David McL. Roberts "British and other freshwater ciliated protozoa Part II Ciliophora: Oligohymenophora and Polyhymenophora" Cambridge University Press, 1983 (ref. ID; 2014)

[ref. ID; 2575]
Ophryoglena, some species of Tetrahymena and Prorodon, and other histophagous Ciliates, attracted by the fresh tissues, have a typical life cycle, through the stages of theront, trophont, tomont, tomites, theronts, which represent characteristic physiological states, i.d.: search for food, its ingestion, digestion and assimilation, and reproduction. The morphological distinction of these stages, the possibility of getting them easily, or to modify at will their functional behavior, render these histophagous Ciliates, particularly Ophryoglena, valuable cells. (ref. ID; 2575)

Ophryoglena atra Liberkuhn, 1856 (ref. ID; 1622, 3116) reported year? (ref. ID; 1618) reported author and year? (ref. ID; 4611)
Description; Oval, posterior end broadly rounded; grayish; filled with globules; cytostome near anterior end; macronucleus elongated; a contractile vacuole; trichocysts; stagnant fresh water. (ref. ID; 1618)
Measurements; 300-500 um long. (ref. ID; 1618)
Ophryoglena collini Lichtenstein, 1921 (ref. ID; 1622) reported year? (ref. ID; 1618)
Description; Pyriform; macronucleus horseshoe-shape; in the caecum of Baetis larvae. (ref. ID; 1618)
Measurements; 200-300 by 120-230 um. (ref. ID; 1618)
Ophryoglena intestinalis Rossolimo, 1926 (ref. ID; 1622) reported year? (ref. ID; 1618)
Description; In the gastrovascular cavity of Dicotylus sp. (ref. ID; 1618)
Measurements; Up to 1.5 mm. by 450-500 um; smallest 60 um long. (ref. ID; 1618)
Ophryoglena parasitica Andre, 1909 (ref. ID; 1622) reported year? (ref. ID; 1618)
Description; Ovoid; dark; micronucleus (?); in the gastrovascular cavity of Dendrocoelum lacteum. (ref. ID; 1618)
Measurements; 170-350 by 180-200 um. (ref. ID; 1618)
Ophryoglena pyriformis Rossolimo, 1926 (ref. ID; 1622) reported year? (ref. ID; 1618)
Description; Flask-shape; in the gastrovascular cavity of various Turbellaria. (ref. ID; 1618)
Measurements; 240-300 um long. (ref. ID; 1618)