Terreneuvian Orthothecid (Hyolitha) Digestive Tracts from Northern Montagne Noire, France; Taphonomic, Ontogenetic and Phylogenetic Implications
Figure 1
A, Reconstruction of the hyolithid conch Joachimilites novaki [23] with proturding helens and in situ operculum. External (left) and internal (right) surfaces of operculum are detailed. l: ligula; h: helens; CaS: cardinal shield; r: rooflet; CoS: conical shield; cp: cardinal process; cl: clavicle; modified after [8], [56]. B, Reconstruction of the orthothecid conch Nephrotheca housina [23] with in situ operculum and detail of external (left) and internal (right) surfaces of operculum. p: process; lc: clavicle-like structure; modified after [23].