''Brachionus plicatilis'' is a euryhaline (tolerate a wide range of

salinity Salinity () is the saltiness or amount of salt (chemistry), salt dissolved in a body of water, called saline water (see also soil salinity). It is usually measured in g/L or g/kg (grams of salt per liter/kilogram of water; the latter is dimensio ...

)

rotifer The rotifers (, from Latin 'wheel' and 'bearing'), sometimes called wheel animals or wheel animalcules, make up a phylum (Rotifera ) of microscopic and near-microscopic Coelom#Pseudocoelomates, pseudocoelomate animals. They were first describ ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

'' Brachionidae'', and is possibly the only commercially important rotifer, being raised in the

aquaculture Aquaculture (less commonly spelled aquiculture), also known as aquafarming, is the controlled cultivation ("farming") of aquatic organisms such as fish, crustaceans, mollusks, algae and other organisms of value such as aquatic plants (e.g. Nelu ...

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 Ecology () is the natural science of the relationships among living organisms and their Natural environment, environment. Ecology considers organisms at the individual, population, community (ecology), community, ecosystem, and biosphere lev ...

and

evolution Evolution is the change in the heritable Phenotypic trait, characteristics of biological populations over successive generations. It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, re ...

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.

Genome size

Haploid '1C' genome sizes in the ''Brachionus plicatilis'' species complex range at least from 0.056 to 0.416 pg. The complete mitochondrial genome of B. plicatilis sensu stricto NH1L has been sequenced.

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.
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 L = larger body and genome sizes e.g. B. plicatilis s.s., clade SM = medium body and genome sizes e.g. B. 'Almenara', clade SS = 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 () 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', S.? (B) # * B02: unnamed, S. 6 (B) # * B03: B. 'Persia', S. ? (B) # * B04: B. 'Harvey', S. 14 (B) # * B05: B. ibericus, S. 10 (B) # * B06: B. Almenara (or MEG-2012), S. 9 (B) # * B07: B. 'Towerinniensis, S. 7 (B) # * B08: B. 'Coyrecupiensis', S. 8 (B) # * B09: B. 'Cayman' (or B. koreanus), S. 5 (B) # * B10: B. 'Cayman' (or B. koreanus), S. 5 (B) # * B11: B. 'Austria', S. 4 (A) # * B12: B. Nevada, S. 3 (A) # * B13: B. Nevada, S. 3 (A) # * B14: B. Nevada, S. 3 (A) # * B15: B. plicatilis s.s., S. 1 (A) # * B16: B. manjavacas, S. 2 (A) # * B17: unnamed, S. 12 (C) # * B18: unnamed, S. 12 (C) # * B19: unnamed, S. 12 (C) # * B20: B. rotundiformis, S. 11 (C) # * B21: unnamed, S. ? (C) # * B22: B. 'Lost', S. 13 (C) #

References

{{Taxonbar, from=Q2488359 Brachionidae Laboratory animals Animals described in 1786