FIGURE 3 in A morphological re-study of three spinicaudatan species from the Middle-Upper Jurassic of Gansu Province, northwestern China

FIGURE 3. Triglypta shandanensis (Chen in Zhang et al., 1976) emend. SEM images of the holotype specimen in Fig. 1A (NIGP 29776). A, The external mould of the left valve. B–D, Growth bands in the middle part of the carapace, ornamented by puncta, appearing as fine nodules on external mould. E, F, Growth bands near the antero-ventral margin of the carapace, ornamented by radial lirae, which are formed by linearly arranged clustered puncta, fine striae with intercalated clustered nodules on external mould. G, Growth bands near the postero-ventral margin of the carapace, ornamented by dense punctate reticulation, appearing as dense nodules on external mould. Scale bars = 1 mm in A, 100 μm in B–G.