Figure 2

Posterior ciliary belts of the P. dumerilii larva. Bottom views of developing larvae showing the changing region of the future pygidium. Nuclei are stained with DAPI (grey) and cilia with an anti-acetylated tubulin antibody. Views are 3D renderings of confocal stacks of images, made with Image J. The telotroch cilia have been false-colored in green whereas prototroch and paratroch cilia are colored in red. A: schematic representation of the perspective chosen for the 3D rendering, the presumptive pygidial territory is colored in cyan. B-D: 3D reconstructions of larvae at 30, 48 and 60 hpf, respectively. The presumptive pygidium is delineated with blue dashed lines. pr – prototroch; p2 and p3 – paratrochs of the second and third chaetigerous segments respectively; tt – telotroch; st – stomodeum; cp – pygidial cirri.