Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Phylum Sipuncula Peanut Worms 1 Phylum Sipuncula Peanut Worms Defining Characteristics – Anterior part of the body forms an eversible and fully retractable proboscis with a mouth at the end – Multicellular bodies (urns) in the coelomic fluid Eversible proboscis 2 Phylum Sipuncula Sipunculan Body Plan 3 Phylum Sipuncula Peanut Worm Feeding 4 Mucus covered tentacles trap organic material from the surrounding water or sediment During burrow formation sediment may be ingested directly Mouth and anus are both located anteriorly resulting in a U shaped gut Phylum Sipuncula Sipunculan Anatomy Circulatory System 6 Unlike the annelids sipunculans lack a circulatory system with a heart and blood vessels Excretion occurs via urns – Cells that float in the coelom collecting waste products bringing them to nephridia Phylum Sipuncula Reproduction Sexes are separate and fertilization occurs in the sea – 7 Trochophore larvae forms resembling Annelida and Mollusca larvae Some species have a trochophore that further develops into a pelagosphera Phylum Sipuncula Local Species – 8 Hermit Sipunculan (Phascolion strombus) – Lives in the shells of gastropods Rock-Boring Sipunculan (Themiste alutacea) – Associated with calcareous surfaces (coral and limestone) Burrowing Sipunculan (Sipunculus nudus) – Burrows in fine and coarse sands Phylum Sipuncula