Fig. 4

3D visualisation of Alviniconcha gross anatomy based on computed tomography (CT). Images are from the A. kojimai specimen scanned using computed tomography. A more detailed interactive model of this specimen is embedded in Supplementary figure 1 and a second interactive model for A. strummeri is included in Supplementary figure 2. Note that for clarity purposes, some tissues and features present in the interactive model, are not included in the above 3D visualisation (but see Figs. 6 and 8). Abbreviations: 1° EBV Primary efferent branchial vessel; AA Anterior aorta; ADD Anterior digestive duct; AOe Anterior oesophagus; BC Buccal cavity; BM Buccal mass; CpV Cephalopedal Vein; Ct Ctenidium; CT Cephalic tentacles; DF Dorsal fold; DG Digestive gland; Ft Foot; Gd Gonoduct; Go Gonad; H Heart; HF Head-foot; In Intestine; MOe Mid-oesophagus; mPOe Mid-posterior oesophagus; Ne Nephridium; NR Oesophageal nerve ring; OeP Oesophageal pouches; Op Operculum; PDD Posterior digestive duct; PF Pallial fringe; POe Lower posterior oesophagus; PS Pallial skirt; R Radula; Re Rectum; SD Salivary ducts; SG Salivary glands; Sn Snout; St Stomach; uPOe Upper posterior oesophagus; VM Visceral mass. Figure is of 3D renderings with exaggerated perspective, thus scales are approximate