Figure 9
From: Origin and evolutionary plasticity of the gastric caecum in sea urchins (Echinodermata: Echinoidea)
Comparative anatomy of the sea urchin digestive tract. (A-T) Aboral views of 3D models that were produced based on magnetic resonance imaging scans of 20 sea urchin species. Cidaridae (A), Micropygidae (B), Diadematidae (C), Stomopneustidae (D), Arbaciidae (E), Saleniidae (F), Temnopleuridae (G), Trigonocidaridae (H), Parechinidae (I), Echinometridae (J), Strongylocentrotidae (K), Echinoneidae (L), Cassidulidae (M), Echinolampadidae (N), Clypeasteridae (O), Laganidae (P), Rotulidae (Q), Echinarachniidae (R), Pourtalesiidae (S), Schizasteridae (T). Dark blue = main digestive tract (comprising the lateral dilation in "regular" euechinoid species (B-K)); cyan = thin-walled pouch(es) in irregular sea urchin species. Not to scale.