Database details : World list of Acoelomorpha

Full name: World list of Acoelomorpha NEW!
Short name: WoRMS Acoelomorpha
Version: 01-Nov-2014
Release date: 2014-11-01
Authors/editors: Tyler S. & Artois T.
Taxonomic coverage: Animalia - Xenacoelomorpha - Acoelomorpha
English name of the group:
Number of species 428
Number of infraspecific taxa 11
Number of synonyms: 220
Number of common names: 0
Total number of names: 648
Abstract: Small ciliated worms known as acoels and nemertodermatids comprise the Acoelomorpha. Their position among other bilaterian animals is not clear, but a recent genomic study (Phillipe et al., 2011) placed them within the Deuterostomia, in a phylum Xenacoelomorpha that includes also the enigmatic sack-like animal Xenoturbella). Xenacoelomorpha is placed as sister group to the Ambulacraria (Echinodermata + Hemichordata). Earlier proposals that Acoelomorpha was the most primitive bilaterian group are likely to be a result of a statistical error known as long-branch attraction. Relationships of species within the Acoelomorpha are no less certain. Their relatively simple morphology offers few characters to determine relationships and still too few of them have been examined for significant molecular-sequence data. Especially the smaller and probably more primitive species living in sediments are little studied; more is known of the more derived and larger acoels such as the convolutids. The current framework from molecular-sequence data, reflected in the hierarchy shown in this database, comes from Jondelius et al., 2011. Data have been contributed to the Catalogue of Life via the WoRMS, hosted by the Flanders Marine Institute (VLIZ).
Organization: School of Biology and Ecology, University of Maine, Orono ME, USA; Hasselt University, Diepenbeek, Belgium
Website: http://www.marinespecies.org