title: Global diversity of the Placozoa.
abstract: The enigmatic animal phylum Placozoa holds a key position in the metazoan Tree of Life. A simple bauplan makes it appear to be the most basal metazoan known and genetic evidence also points to a position close to the last common metazoan ancestor. Trichoplax adhaerens is the only formally described species in the phylum to date, making the Placozoa the only monotypic phylum in the animal kingdom. However, recent molecular genetic as well as morphological studies have identified a high level of diversity, and hence a potential high level of taxonomic diversity, within this phylum. Different taxa, possibly at different taxonomic levels, are awaiting description. In this review we firstly summarize knowledge on the morphology, phylogenetic position and ecology of the Placozoa. Secondly, we give an overview of placozoan morphological and genetic diversity and finally present an updated distribution of placozoan populations. We conclude that there is great potential and need to erect new taxa and to establish a firm system for this taxonomic tabula rasa.
authors.affiliation: Stiftung Tierärztliche Hochschule Hannover, Institut für Tierökologie und Zellbiologie, Ecology and Evolution, Hannover, Germany. meitel@hku.hk
authors.forename: Michael
authors.initials: M
authors.lastname: Eitel
authors.forename: Hans-Jürgen
authors.initials: HJ
authors.lastname: Osigus
authors.forename: Rob
authors.initials: R
authors.lastname: DeSalle
authors.forename: Bernd
authors.initials: B
authors.lastname: Schierwater
mesh_terms: D000818:Animals; D044822:Biodiversity; D019143:Evolution, Molecular; D014644:Genetic Variation; D054629:Genome, Mitochondrial; D005843:Geography; D008969:Molecular Sequence Data; D010802:Phylogeny; D054909:Placozoa / Q000033:anatomy & histology / Q000145:classification* / Q000235:genetics; D011157:Population Dynamics; D012336:RNA, Ribosomal, 16S; D012339:RNA, Ribosomal, 28S
chemical_list: D012336:RNA, Ribosomal, 16S; D012339:RNA, Ribosomal, 28S
references.citation: Genetika. 2004 Dec;40(12):1714-6
references.pmid: 15648156
references.citation: Dev Genes Evol. 2004 Apr;214(4):170-5
references.pmid: 14997392
references.citation: Biosystems. 1999 Dec;54(1-2):65-70
references.pmid: 10658838
references.citation: PLoS Biol. 2009 Jan 27;7(1):e20
references.pmid: 19175291
references.citation: PLoS Biol. 2011 Mar;9(3):e1000602
references.pmid: 21423652
references.citation: Z Naturforsch C J Biosci. 2014 Jun 02;50(3-4):282-285
references.pmid: 37978785
references.citation: Syst Biol. 2005 Oct;54(5):844-51
references.pmid: 16243769
references.citation: Int J Biochem Cell Biol. 2009 Feb;41(2):370-9
references.pmid: 18935972
references.citation: Proc Natl Acad Sci U S A. 2005 Oct 25;102(43):15518-22
references.pmid: 16230622
references.citation: Nature. 2010 Aug 5;466(7307):720-6
references.pmid: 20686567
references.citation: Proc Natl Acad Sci U S A. 2006 Jun 6;103(23):8751-6
references.pmid: 16731622
references.citation: Mol Biol Evol. 2009 Jun;26(6):1333-40
references.pmid: 19276153
references.citation: Bioessays. 2005 Dec;27(12):1294-302
references.pmid: 16299758
references.citation: Brief Bioinform. 2008 Jul;9(4):286-98
references.pmid: 18372315
references.citation: Nucleic Acids Res. 2005 Jan 20;33(2):511-8
references.pmid: 15661851
references.citation: Z Naturforsch C Biosci. 1974 Nov-Dec;29(11-12):790
references.pmid: 4281212
references.citation: Nature. 2008 Aug 21;454(7207):955-60
references.pmid: 18719581
references.citation: PLoS Genet. 2007 Jan 12;3(1):e13
references.pmid: 17222063
references.citation: Mol Ecol. 2010 Jun;19(11):2315-27
references.pmid: 20604867
references.citation: Commun Integr Biol. 2009 Sep;2(5):403-5
references.pmid: 19907700
references.citation: Trends Genet. 2009 Sep;25(9):381-6
references.pmid: 19716620
references.citation: Philos Trans R Soc Lond B Biol Sci. 2005 Oct 29;360(1462):1905-16
references.pmid: 16214748
references.citation: PLoS One. 2011;6(5):e19639
references.pmid: 21625556
references.citation: Zoolog Sci. 2012 Apr;29(4):223-8
references.pmid: 22468831
references.citation: J Morphol. 2011 Mar;272(3):371-8
references.pmid: 21246596
references.citation: Curr Biol. 2004 Nov 23;14(22):R944-5
references.pmid: 15556848
references.citation: Bioessays. 2008 Nov;30(11-12):1043-7
references.pmid: 18937347
references.citation: Biol Bull. 2004 Feb;206(1):55-60
references.pmid: 14977730
references.citation: Dev Genes Evol. 2010 Dec;220(7-8):221-34
references.pmid: 21069538
references.citation: Trends Ecol Evol. 1994 Jan;9(1):27-31
references.pmid: 21236760
references.citation: Biol Bull. 2006 Oct;211(2):149-56
references.pmid: 17062874
references.citation: Science. 2009 Feb 6;323(5915):741-6
references.pmid: 19197054
references.citation: Integr Comp Biol. 2007 Nov;47(5):677-92
references.pmid: 21669749
references.citation: Mol Phylogenet Evol. 2013 Feb;66(2):551-7
references.pmid: 22683435
references.citation: Cladistics. 2010 Aug;26(4):444-452
references.pmid: 34875804