FIGURE 4 in The dorsal plate is a critical feature in the reassessment of the rotiferan genus Ptygura (Monogononta; Gnesiotrocha; Flosculariidae)

FIGURE 4. Comparison of dorsal plate bearing species with species lacking a dorsal plate. A: Lateral view of the anterior half of Ptygura ctenoida showing the corona ciliature (cc), the mouth (m), the dorsal plate (DP), the short hooks (h), and the trunk (t). B: Dorsal view of the anterior half of Ptygura sp. showing the corona ciliature (cc), the apical field of the corona (af), the dorsal gap in the corona ciliature (dg), a lateral antenna (la), the trunk (t), the cloaca opening (cl), and part of the foot (f). C: trunk (t) and head of a specimen of Ptygura thalenoiensis showing the dorsal antenna opening (da) located in the middle of a pair of dorsal hooks (dh), the lateral antennae (la), the opening of corona and mouth (mco), and the papillate ring on the trunk (pr). D: closeup of the paired dorsal hooks (dh) and dorsal antenna opening (da) of another specimen of Ptygura thalenoiensis; note the grooves and ridges of the integument. Bars: 20 µm for A, B, and C; 5 µm for D.