FIGURE 2 in Spirobranchus bakau sp. nov. from Singapore: yet another species of S. kraussii-complex (Polychaeta: Serpulidae)

FIGURE 2. Spirobranchus bakau sp. nov. tubes. A—Cluster of tubes from mangroves at Lim Chu Lang end (photographed ex situ); B, C—Top view of individual tubes; D–F—Cross-sectional views of tubes, showing variation in shapes of tube mouths and lumina: sub-trapezoidal cross-section (D–F), ovoid lumen (D) and circular lumen (E–F); G—Top view of tube with winglike keel structures; inset figure shows cross-sectional view of tube; H—Lateral keels that run along sides of tube of paratype ZRC.ANN.0481 (indicated by red arrows). Scale bars—A: 5 mm, B–H (including inset figure): 0.5 mm.