FIGURE 4 in Phylum Tardigrada: A re-evaluation of the Parachela

FIGURE 4. Stylised diagrams of the apophysis for the insertion of the stylet muscles (AISM) (in lateral view, left —dorsal, right—ventral). Hook shaped AISM of Hypsibioidea, Hypsibiidae, Hypsibiinae: A. Hypsibius, simple hooks; B. Borealibius, modified spherical hooks; C. Acutuncus, accentuated hooks. Modified hook shaped AISM of Hypsibioidea, Microhypsibiidae: D. Microhypsibius, accentuated hook and hook with ridge. Modified hook shaped AISM of Hypsibioidea, Calohypsibiidae: E. Calohypsibius, triangular hook and triangular hook with triangular ridge. Modified hook shaped AISM of Hypsibioidea, Ramazzottidae: F. Hebesuncus, asymmetric triangular and basic hook, G. Ramazzottius, asymmetric hooks. Ventral crest ASIM of the Macrobiotoidea, Macrobiotidae: H. Macrobiotus, asymmetric crest, 10 peribuccal lamellae present. Ventral crest ASIM of the Macrobiotoidea, Murrayidae: I. Dactylobiotus, asymmetric crest with hook, 10 peribuccal lamellae present. Ridge shaped AISM of Eohypsibioidea, Eohypsibiidae: J. Eohypsibius, Broad ridges widening mouth with 14 peribuccal lamellae. Ridge shaped AISM of Isohypsibioidea, Isohypsibiidae: K. Isohypsibius, simple triangular ridges, L. Thulinius, simple undulating ridges, 12 peribuccal lamellae present, M. Pseudobiotus, simple undulating ridges, 30 peribuccal lamellae present, N. Mixibius, modified ridges with small gap, and O. Doryphoribius, asymmetric crest ridge.