FIGURE 4 in Spirobranchus bakau sp. nov. from Singapore: yet another species of S. kraussii-complex (Polychaeta: Serpulidae)

FIGURE 4. Structural variation in opercular peduncles and talons in specimens of Spirobranchus bakau sp. nov.. A—Dorsal view of specimen, showing peduncle insertion on the left of median line, with peduncular wings tapering diagonally to the central axis of the operculum; B—Peduncular wings tapering perpendicularly to the central axis of the operculum; C—Wing tips end abruptly as if truncated; D—Top view of opercular endplate showing ovoid concentric layers with shallow depression in innermost layer; E—Opercular talon with bifid terminal region; F—Underside of opercular endplate showing position of talon relative to edges of endplate; G—Opercular talon of holotype (ZRC.ANN.0480) with trifid terminal region; H—Lateral view of talon of holotype (ZRC.ANN.0480); I—Talon of paratype (ZRC.ANN.0486) with protuberances from endplate on each side of peg and wing-shaped protuberance from the peg. Scale bars—A–I: 0.5 mm.