Petz, Song & Wilbert (1995: 84, fig. 24)
In vivo 50–55 × 25–30 µm. Body reniform, anteriorly obliquely truncate, without a frontal plate; oral cavity small, invaginated in anterior third of body; laterally flattened. Somatic kineties 38–46, densely ciliated, curving around oral cavity on right, 1 or 2 kineties on either side of oral area posteriorly shortened; caudal cilium 1, fine, rather short (c. 16 µm long). Adoral membranelles 3, small; curved paroral membrane short. Scutica composed of c. 5–9 kinetosomes. Extrusomes (mucocysts) inconspicuous, in interkinetal rows. Macronucleus 1; micronucleus 1. Contractile vacuole terminal. Movement: moderately fast, rotating slightly spirally about main body axis when swimming, rests for feeding.
Weddell Sea (Petz et al., 1995).