taxonomy sourceWagin, V. L. (Vladimir Lvovich). (2007). On the annelid theory about the origin of myzostomids, their position in the system of Trochozoa, and identification of the new phylum Myzostomida. (In Russian). <em>Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki.</em> 149 (3): 31–41., available online athttps://elibrary.ru/item.asp?id=11137617 note: raised to phylum [details] Available for editors [request]
additional sourceHelm, Conrad; Stevenson, Paul A.; Rouse, Greg W.; Bleidorn, Christoph. (2014). Immunohistochemical investigations of Myzostoma cirriferum and Mesomyzostoma cf. katoi (Myzostomida, Annelida) with implications for the evolution of the myzostomid body plan. <i>Zoomorphology</i>. 133(3): 257-271., available online athttps://doi.org/10.1007/s00435-014-0221-z page(s): [evolution of segmentation] [details]
status sourceMwinyi, A.; Meyer, A.; Bleidorn, C.; Lieb, B.; Bartolomaeus, T.; Podsiadlowski, L. (2009). Mitochondrial genome sequence and gene order of Sipunculus nudus give additional support for an inclusion of Sipuncula into Annelida. <i>BMC Genomics</i>. 10(1): 27., available online athttps://doi.org/10.1186/1471-2164-10-27[details]
status sourceWang, Y.; Xie, Q. (2014). The Molecular Symplesiomorphies Shared by the Stem Groups of Metazoan Evolution: Can Sites as Few as 1% Have a Significant Impact on Recognizing the Phylogenetic Position of Myzostomida?. <i>Journal of Molecular Evolution</i>. 79(1-2): 63-74., available online athttps://doi.org/10.1007/s00239-014-9635-y page(s): [Position of Myzostomida unresolved] [details]
status sourceBleidorn, C.; Helm, C.; Weigert, A.; Eeckhaut, I.; Lanterbecq, D.; Struck, T. H.; Hartmann, S.; Tiedemann, R. (2014). From morphology to phylogenomics: Placing the enigmatic Myzostomida in the tree of life. <em>[Book section].</em> 161-172 In: Deep Metazoan Phylogeny: The Backbone of the Tree of Life, edited by Wägele, Wolfgang & Bartolomaeus, Thomas., available online athttps://doi.org/10.1515/9783110277524.161[details]
status sourceWagin, V. L. (Vladimir Lvovich). (2007). On the annelid theory about the origin of myzostomids, their position in the system of Trochozoa, and identification of the new phylum Myzostomida. (In Russian). <em>Uchenye Zapiski Kazanskogo Universiteta. Seriya Estestvennye Nauki.</em> 149 (3): 31–41., available online athttps://elibrary.ru/item.asp?id=11137617 note: an article published many years after Wagin had died. [details] Available for editors [request]
Classification Myzostomida have apparent morphological affinities to Polychaeta, and have been treated as a group within Phyllodocida. The position of Myzostomida is unresolved and recent molecular studies have not placed Myzostomida close to Polychaeta (uncertain if real or artifactual placement), although authors find similarities (just for example their planktonic larvae look very polychaete like). Myzostomida are placed in Annelida based on mitochondrial gene orders (Mwinyi et al. 2009). Most recently Bleidorn et al (2014) wrote "Placing the myzostomids in the Annelida is the best supported and most plausible hypothesis in the light of the current data"
However, there have been contrary views. As recently as 2000 it was concluded (Eeckhaut et al, 2000) that "analyses strongly reject the grouping of myzostomids with any subgroup of annelids.This does not really conflict with morphological data because, although myzostomids are most often considered as polychaete annelids, not a single morphological synapomorphy (i.e. a shared derived character state) linking the two taxa has been unambiguously identified. Indeed, the character states usually put forward for grouping myzostomids and polychaetes (the presence of chaetae and a trochophore larva) are encountered in other spiralian groups: chaetae occur in the Clitellata, Pogonophora, Echiura, and some Mollusca and Brachiopoda (Specht 1988), and trochophores are found in the development of some Mollusca, Sipuncula, Echiura and Pogonophora (Heimler 1987). " As recently as 2007 (Wagin, 2007) the Myzostomida were raised to a separate phylum status. This appears to be the only publication ever to treat myzostomids at phylum-level. Wagin (2007) was a posthumous publication some twenty years after his death [details] Ecology Most Myzostomida are free-living associates of crinoid echinoderms. Some are encysted by the host in galls, some are endoparasitic. Others live on basket-stars, asteroids, or ophiuroids. Jumars et al (2015:A169) have further family-level feeding analysis [details]