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Peanut Worms

taxon links [down<--]Bilateria Phylogenetic position of group is uncertain Monophyly Uncertain Phylogenetic position of group is uncertain Monophyly Uncertain Phylogenetic position of group is uncertain Phylogenetic position of group is uncertain Phylogenetic position of group is uncertain Phylogenetic position of group is uncertain Interpreting the tree
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The root of the current tree connects the organisms featured in this tree to their containing group and the rest of the Tree of Life. The basal branching point in the tree represents the ancestor of the other groups in the tree. This ancestor diversified over time into several descendent subgroups, which are represented as internal nodes and terminal taxa to the right.

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Relationships after Maxmena et al. 2003.
Containing group: Bilateria

Discussion of Phylogenetic Relationships

Sipunculidea (Sipunculidae + Golfingiiformes), Sipunculidae (Sipunculus + Xenosiphon + Siphonosoma + Siphonomecus + Phascolopsis), and Phascolosomatidae (Phascolosoma + Apionsoma + Antillesoma) of Cutler (1994) are most likely not monophyletic (Maxmena et al. 2003).


Cutler, E. B. 1994. The Sipuncula, their systematics, biology, and evolution. Cornell University Press, Ithaca, NY.

Cutler, E. B. and P. E. Gibbs. 1985. A phylogenetic analysis of higher taxa in the phylum Sipuncula. Systematic Zoology 34:162-173.

Edmonds, S. J. 2000. Phylum Sipuncula. Pages 375–400 in: Polychaetes & Allies: The Southern Synthesis. Fauna of Australia, vol. 4A, Polychaeta, Myzostomida, Pogonophora, Echiura, Sipuncula. P. L. Beesley, G.J.B. Ross, and C.J. Glasby, eds. CSIRO Publishing, Melbourne.

Ferrier, D. and P. W. H. Holland. 2001. Sipunculan ParaHox genes. Evol. Dev. 3:263-70

Huang, D. Y., J.-Y. Chen, J. Vannier, and J. I. Saiz Salinas. 2004. Early Cambrian sipunculan worms from southwest China. Proceedings of the Royal Society of London Series B 271(1549):1671-1676.

KennetLundin, K. and C.Schander. 2003. Epidermal ciliary ultrastructure of adult and larval sipunculids (Sipunculida). Acta Zoologica 84(2):113-119.

Maxmena, A. B., B. F. King, E. B. Cutler and G. Giribet. 2003. Evolutionary relationships within the protostome phylum Sipuncula: a molecular analysis of ribosomal genes and histone H3 sequence data. Molecular Phylogenetics and Evolution 27(3):489-503.

Rice, M. E. 1985. Sipuncula: developmental evidence for phylogenetic inference. Pages 274-296 in The Origins and Relationships of Lower Invertebrates. S. C. Morris, J. D. George, R. Gibson and H. M. Platt, eds. Oxford University Press, Oxford.

Rice, M. E. 1993. Sipuncula. Pages 238–325 in: Microscopic Anatomy of Invertebrates, Vol. 12: Onychophora, Chilopoda, and Lesser Protostomata. F. W. Harrison and M. E. Rice, eds. Wiley-Liss, New York.

Information on the Internet

Title Illustrations
Scientific Name Phascolopsis gouldii
Creator David Remsen
Copyright © 1995 Marine Biological Laboratory, Woods Hole
About This Page
Citing this page:

Maddison, David R. 1999. Sipuncula. Peanut Worms. Version 01 January 1999 (temporary). http://tolweb.org/Sipuncula/2487/1999.01.01 in The Tree of Life Web Project, http://tolweb.org/

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