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''Brachionus plicatilis'' is a euryhaline (tolerate a wide range of salinity) rotifer in the Family ''Brachionidae'', and is possibly the only commercially important rotifer, being raised in the aquaculture industry as food for fish larvae. It has a broad distribution in salt lakes around the world and has become a model system for studies in ecology and evolution. Reproduction Brachionus species can normally reproduce asexually and sexually (cyclical parthenogenesis). Sexual reproduction (termed Mixis) is usually induced when population density increases. Mixis in Brachionus plicatilis has been shown to be induced by a density-dependent chemical cue.〔Induction of sexual reproduction in Brachionus plicatilis (Monogononta, Rotifera) by a density-dependent chemical cue CP Stelzer, TW Snell - Limnology and Oceanography, 2003 〕 Genome size Haploid '1C' genome sizes in the ''Brachionus plicatilis'' species complex range at least from 0.056 to 0.416 pg.〔Stelzer CP, Riss S and Stadler P. (2011): Genome size evolution at the speciation level: the cryptic species complex Brachionus plicatilis (Rotifera). BMC Evol Biol. 2011 Apr 7;11:90. () 〕 The complete mitochondrial genome of B. plicatilis sensu strictu NH1L has been sequenced.〔Koushirou Suga, David B. Mark Welch, Yukari Tanaka, Yoshitaka Sakakura, and Atsushi Hagiwara (2008). Two Circular Chromosomes of Unequal Copy Number Make Up the Mitochondrial Genome of the Rotifer Brachionus plicatilis Mol Biol Evol (2008) 25(6): 1129-1137〕 Cryptic species complex Brachionus plicatilis strains have long been divided into ‘L-’ and ‘S-type’ forms. However, studies on morphology, karyotype, genetics and reproductive behaviour revealed that these types seem to be different species (B. plicatilis and B. rotundiformis). DNA sequencing studies in 2002 revealed ''Brachionus plicatilis'' to be a cryptic species complex comprising approximately 10 separate species, each of which has been diverging for several million years.〔 〕 A recent study identified 22 potential different species within the Plicatilis species complex. 〔Extreme levels of hidden diversity in microscopic animals (Rotifera) revealed by DNA taxonomy D Fontaneto, M Kaya, EA Herniou… - Molecular Phylogenetics …, 2009 - Elsevier〕 The species, rather than the complex, is now usually referred to as ''Brachionus plicatilis'' s. s. (sensu stricto). The species complex can be divided into 3 major clades (clade A = larger body and genome sizes e.g. B. plicatilis s.s., clade B = medium body and genome sizes e.g. B. 'Almenara', clade C = small body and genome size e.g. B. rotundiformis). http://www.biomedcentral.com/1471-2148/11/90/figure/F1 List of the 22 suspected species of the B. plicatilis cryptic species complex - Species names and clade in () 〔Extreme levels of hidden diversity in microscopic animals (Rotifera) revealed by DNA taxonomy D Fontaneto, M Kaya, EA Herniou… - Molecular Phylogenetics …, 2009 - Elsevier〕〔Diversity of the rotifer Brachionus plicatilis species complex (Rotifera: Monogononta) in Iran through integrative taxonomy Reza Malekzadeh-Viayeh1, *, Razieh Pak-Tarmani1, Nasim Rostamkhani2 and Diego Fontaneto3 Article first published online: 7 JAN 2014 DOI: 10.1111/zoj.12106〕 # * B01: B. 'Tiscar', 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Brachionus plicatilis」の詳細全文を読む スポンサード リンク
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