Within the diversity exhibited by rotifers, superorder Gnesiotrocha are distinct from superorder Pseudotrocha (order Ploima) in that all gnesiotrochans (1) possess a foot that lack toes, (2) their anterior end is either a funnel-shaped structure or possesses ciliated lobes, and (3) their trophi are either malleoramate or uncinate (Edmondson 1959; Koste 1978; Ruttner-Kolisko 1974; Wallace & Snell 2010; Wallace et al. 2006). Ploimids may lack a foot, and, if present, may possess toes; their anterior end and trophi do not resemble that of the sessile taxa. Uncinate trophi possess few teeth: usually one or more large, pincer-like teeth and a few smaller teeth (Fig. 2A); malleoramate trophi possess crescent-shaped manubria and unci with numerous club-shaped teeth (Fig. 2B). Teeth close to the fulcrum are usually larger than those more distant. Trophi in the Flosculariaceae characteristically exhibit a grinding or pounding-like action, which is not seen in the Collothecacea.