Myogenesis in two polyclad platyhelminths with indirect development, Pseudoceros canadensis and Stylostomum sanjuania.

摘要: SUMMARY Myogenesis of two representatives Platyhelminthes, Stylostomum sanjuania and Pseudoceros canadensis, was followed from egg deposition until well-differentiated free-swimming larval stages, using F-actin staining confocal laserscanning microscopy. Zonulae adhaerentes are the only structures to stain before 50% development between hatching in S. sanjuania, 67% P. canadenis. Subsequently, irregular fibers appear embryo, by a helicoid muscle close apical pole. Three longitudinal pairs form, which dorsal pair remains more pronounced than others. Gradually, new muscles form branching or double-stranded zones adjacent existing muscles. This results an elaborate muscular bodywall that consists single as well multiple circular Diverse retractor insert at sphincter around stomodeum. The overall arrangement formation mode musculature appears very similar both species, although canadensis has primary posterior muscle. Muscle region embryo precedes abapical pole slightly later myoanatomy highly conserved among polyclad flatworms, but differs significantly other trochozoan clades. Our data suggest ground pattern larvae comprises consisting muscle, muscles, several