Molecular phylogenetic analyses indicate multiple independent emergences of parasitism in Myzostomida (protostomia)
Lanterbecq, D.; Rouse, G.W.; Milinkovitch, M.C.; Eeckhaut, I. (2006). Molecular phylogenetic analyses indicate multiple independent emergences of parasitism in Myzostomida (protostomia). Syst. Biol. 55(2): 208-227. https://hdl.handle.net/10.1080/10635150500481317
In: Systematic Biology. Oxford University Press: Washington, D.C.. ISSN 1063-5157; e-ISSN 1076-836X, more
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| Keywords |
Crinoidea [WoRMS]; Echinodermata [WoRMS]; Myzostomida [WoRMS]
Marine/Coastal |
| Author keywords |
character evolution; commensalism; crinoids; echinoderms; molecular phylogeny; myzostomids; symbiosis |
| Authors | | Top |
- Lanterbecq, D., more
- Rouse, G.W.
- Milinkovitch, M.C., more
- Eeckhaut, I., more
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| Abstract |
The fossil record indicates that Myzostomida, an enigmatic group of marine worms, traditionally considered as annelids, have exhibited a symbiotic relationship with echinoderms, especially crinoids, for nearly 350 million years. All known extant myzostomids are associated with echinoderms and infest their integument, gonads, celom, or digestive system. Using nuclear (18S rDNA) and mitochondrial (16S and COI) DNA sequence data from 37 myzostomid species representing nine genera, we report here the first molecular phylogeny of the Myzostomida and investigate the evolution of their various symbiotic associations. Our analyses indicate that the two orders Proboscidea and Pharyngidea do not constitute natural groupings. Character reconstruction analyses strongly suggest that (1) the ancestor of all extant myzostomids was an ectocommensal that first infested crinoids, and then asteroids and ophiuroids, and (2) parasitism in myzostomids emerged multiple times independently. |
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