Acoela

Superregnum: Eukaryota
Cladus: Unikonta
Cladus: Opisthokonta
Cladus: Holozoa
Kingdom: Animalia
Subregnum: Eumetazoa
Cladus: ParaHoxozoa
Cladus: Bilateria
Phylum: Xenacoelomorpha
Subphylum: Acoelomorpha
Classis:
Familiae (16): Actinoposthiidae – Antigonariidae – Antroposthiidae – Convolutidae – Dakuidae – Diopisthoporidae – Hallangiidae – Hofsteniidae – Isodiametridae – Mecynostomidae – Nadinidae – Otocelididae – Paratomellidae – Proporidae – Solenofilomorphidae – Taurididae
[Source: Jondelius et al., 2011]

Acoela Uljanin, 1870

• Achatz, J.G., Chiodin, M., Salvenmoser, W., Tyler, S. & Martinez, P. 2012. The Acoela: on their kind and kinships, especially with nemertodermatids and xenoturbellids (Bilateria incertae sedis). Organisms Diversity & Evolution 13: 267–286. DOI: 10.1007/s13127-012-0112-4 .
• Achatz, J.G., Hooge, M., Wallberg, A., Jondelius, U. & Tyler, S. 2010. Systematic revision of acoels with 9+0 sperm ultrastructure (Convolutida) and the influence of sexual conflict on morphology. Journal of Zoological Systematics and Evolutionary Research 48(1): 9–32. DOI: 10.1111/j.1439-0469.2009.00555.x . [Corrigendum: 48(2): 196. DOI: 10.1111/j.1439-0469.2010.00569.x .] Reference page. 
• Egger, B., Steinke, D., Tarui, H., De Mulder, K., Arendt, D., Borgonie, G., Funayama, N., Gschwentner, R., Hartenstein, V., Hobmayer, B., Hooge, M., Hrouda, M., Ishida, S., Kobayashi, C., Kuales, G., Nishimura, O., Pfister, D., Rieger, R., Salvenmoser, W., Smith, J., III, Technau, U., Tyler, S., Agata, K., Salzburger, W. & Ladurner, P. 2009. To be or not to be a flatworm: the acoel controversy. PLoS ONE 4(5): e5502. DOI: 10.1371/journal.pone.0005502 . Reference page. 
• Faubel, A. & Kolasa, J. 1978. On the anatomy and morphology of a freshwater species of Acoela (Turbellaria): Limnoposthia polonica (Kolasa et Faubel, 1974). Bulletin de L'Academie Polonaise des Sciences serie des sciences biologiques 26: 393–397.
• Hooge, M.D., Haye, P.A., Tyler, S., Litvaitis, M.K. & Kornfield, I. 2002. Molecular systematics of the Acoela (Acoelomorpha, Platyhelminthes) and its concordance with morphology. Molecular Phylogenetics and Evolution 24: 333–342. DOI: 10.1016/S1055-7903(02)00236-1 PDF
• Hooge, M.D. & Tyler, S. 2003. Two new acoels (Acoela, Platyhelminthes) from the central coast of California. Zootaxa 131: 1–14. Abstract & excerpt Reference page. 
• Jondelius, U., Wallberg, A., Hooge, M. & Raikova, O.I. 2011. How the Worm Got its Pharynx: Phylogeny, Classification and Bayesian Assessment of Character Evolution in Acoela. Systematic Biology 60(6): 845–871. DOI: 10.1093/sysbio/syr073 . Reference page. 
• Kånneby, T. & Jondelius, U. 2013. Four new species of Acoela from Chile. Zootaxa 3736(5): 471–485. DOI: 10.11646/zootaxa.3736.5.3 Reference page. 
• Kolasa, J. & Faubel, A. 1974. A preliminary description of a freshwater Acoela (Turbellaria): Oligochoerus polonicus nov. spec. Boll. Zool., 41: 81–85.
• Philippe, H., Brinkmann, H., Copley, R.R., Moroz, L.L., Nakano, H., Poustka, A.J., Wallberg, A., Peterson, K.J. & Telford, M.J. 2011. Acoelomorph flatworms are deuterostomes related to Xenoturbella. Nature 470: 255–258. DOI: 10.1038/nature09676 Reference page. 
• Ruiz-Trillo, I., Riutort, M., Littlewood, D.T.J., Herniou, E.A. & Baguñà, J. 1999. Acoel flatworms: earliest extant bilaterian metazoans, not members of Platyhelminthes. Science 283: 1919–1923. DOI: 10.1126/science.283.5409.1919
• Schockaert, E.R., Hooge, M., Sluys, R., Schilling, S., Tyler, S. & Artois, T. 2008. Global diversity of free living flatworms (Platyhelminthes, “Turbellaria”) in freshwater. Hydrobiologia 595: 41–48. DOI: 10.1007/978-1-4020-8259-7_5 , DOI: 10.1007/s10750-007-9002-8 .
• Zauchner, T., Salvenmoser, W. & Egger, B. 2015. A cultivable acoel species from the Mediterranean, Aphanostoma pisae sp. nov. (Acoela, Acoelomorpha). Zootaxa 3941(3): 401–413. DOI: 10.11646/zootaxa.3941.3.6 Reference page. 

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