FIGURE 1 in Megalomma Johansson, 1925 (Polychaeta: Sabellidae) from America and other world-wide localities, and phylogenetic relationships within the genus 2861

FIGURE 1. Variations on dorsal margins of collar and inferior thoracic chaetae in Megalomma. A–C) Margins fused to faecal groove; D) margins not fused to faecal groove; E) chaeta type A; F) chaeta type B; G) chaeta type C. A–D) Schematized; E–G) modified from Fitzhugh (1989). Abbreviations: dlc dorsal lappets; fg faecal groove. The partial exposition of the anterior peristomial ring is marked in gray.