Apometamera

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Apometamera

animal phylum

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animal
Annotated classification
Phylum Apometamera Unsegmented worms; food-gathering proboscis with cilia below or in tentacles; sedentary tube dwellers; metanephridia; marine; filter feeders; Devonian to recent; 400 species. Phylum Phoronida Wormlike; sedentary in chitinous tube; lophophore; closed circulatory system; metanephridia; marine; filter feeders; Devonian? to recent; 15
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Phylum Apometamera Unsegmented worms; food-gathering proboscis with cilia below or in tentacles; sedentary tube dwellers; metanephridia; marine; filter feeders; Devonian to recent; 400 species. Phylum Phoronida Wormlike; sedentary in chitinous tube; lophophore; closed circulatory system; metanephridia; marine; filter feeders; Devonian? to recent; 15
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animal
Appearance of animals
The Apometamera show traces of segmentation in the Echiura but none in the overall more-derived Sipuncula. Apometamera are also annelid relatives but may be even closer to mollusks. They lack useful fossils, unless the tube-forming Hyolitha, which may alternatively be annelids or a separate phylum and…
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The Apometamera show traces of segmentation in the Echiura but none in the overall more-derived Sipuncula. Apometamera are also annelid relatives but may be even closer to mollusks. They lack useful fossils, unless the tube-forming Hyolitha, which may alternatively be annelids or a separate phylum and…
Read More