On the embryology ofSiboglinumand its implications for the systematic position of the Pogonophora

Publisher Website
Google Scholar
Abstract
The larval development of Siboglinum is described in detail from some new and well fixed material. It was found that gastrulation occurs by epiboli, and mesoderm formation takes place in two separate phases. Some mesoderm is formed on the ventral side of the embryo immediately below the embryonic epidermis. This mesoderm spreads forward on either side of the embryo between ento- and ecto-derm and a constriction is formed near the hind end of the embryo. After the formation of this constriction a second wave of mesoderm is formed from a peripygidial zone. Regular segmentation can be detected in this mesoderm. Ultimately the hind end of the embryo is regularly segmented and carries setae that are very similar to polychaete setae. It is concluded that the embryology of Pogonophora points towards an annelid affinity, possibly close to Archiannelida.

This publication has 6 references indexed in Scilit: