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Arrow Worms

taxon links [down<--]Bilateria Interpreting the tree
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This tree diagram shows the relationships between several groups of organisms.

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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Containing group: Bilateria


Bieri, R. 1991. Systematics of the Chaetognatha. Pages 122-136 in: The Biology of Chaetognaths. Q. Bone Q, H. Knapp, and A. C. Pierrot-Bults, eds. Oxford University Press, Oxford

Bone, Q., H. Knapp, and A. C. Pierrot-Bults, eds. 1991. The Biology of Chaetognaths. Oxford University Press, Oxford.

Casanova, J.-P. 1985. Description de l'appareil g?nital primitif du genre Heterokrohnia et nouvelle classification des Chaetognathes. Compte-rendus hebdomadaires des S?ances de l'Academie des Sciences, Paris, Ser. 3, 301:397-402.

Chen, J.-Y. and D.-Y. Huang. 2002. A possible Lower Cambrian chaetognath (arrow worm). Science 298:187.

Halanych, K. M. 1996. Testing hypotheses of chaetognath origins: long branches revealed by 18S ribosomal DNA. Systematic Biology 45:223–246.

Helfenbein, K. G., H. M. Fourcade, R. G. Vanjani, and J. L. Boore. 2004. The mitochondrial genome of Paraspadella gotoi is highly reduced and reveals that chaetognaths are a sister group to protostomes. Proceedings of the National Academy of Sciences 101(29):10639-10643.

Kapp, H. The unique embryology of Chaetognatha. Zoologischer Anzeiger 239:263-266.

Papillon, D., Y. Perez, X. Caubit, and Y. Le Parco. 2006. Systematics of Chaetognatha under the light of molecular data, using duplicated ribosomal 18S DNA sequences. Molecular Phylogenetics and Evolution 38(3):621-634.

Salvini-Plawen, L. W. 1986. Systematics notes on Spadella and on the Chaetognatha in general. Z. Zool. Syst. Evol. 24:122?128.

Shinn, G. L. and M. E. Roberts. 1994. Ultrastructure of hatching chaetognaths (Ferosagitta hispida): phylogenetic implications. Journal of Morphology 219:143-163.

Tokioka, T. 1965. The taxonomical outline of Chaetognatha. Publications of the Seto Marine Biological Laboratory 12:335-357.

Telford, M. J. 2004. Affinity for arrow worms. Nature 431:254-256.

Telford, M. J., and P. W. H. Holland. 1993. The phylogenetic affinities of the chaetognaths: A molecular analysis. Molecular Biology and Evolution 10:660-676.

Telford, M. J. and P. W. H. Holland. 1997. Evolution of 28S ribosomal DNA in chaetognaths: duplicate genes and molecular phylogeny. Journal of Molecular Evolution 44:135-144.

Information on the Internet

Title Illustrations
Scientific Name Spadella
Creator J. M. Cavanihac
Copyright © BIODIDAC
About This Page
Citing this page:

Tree of Life Web Project. 2002. Chaetognatha. Arrow Worms. Version 01 January 2002 (temporary). http://tolweb.org/Chaetognatha/2478/2002.01.01 in The Tree of Life Web Project, http://tolweb.org/

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