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Taxonomic characters
clearly distinguished from P. californica, P. japonica and P. indica by its individual cellular sheaths that are spherical in shape and separated from one another or weakly attached to each other and absence of a gradual increase in cell size from anterior to posterior pole of colony (Nozaki et al 2006)
Morphology / Structure
colonies ovoid or spherical in shape; 32-64 cells embedded at the periphery of the gelatinous matrix; 8-12 or 18-20 obligative somatic cells (at the anterior pole) in 32- or 64-celled colonies, respectively; no gradual increase in cell size
Life history
heterothallic; anisogamous
To induce sexual reproduction (Nozaki et al 2006): actively growing cultures of male and female strains in 12mL VTAC medium were concentrated to 0.2–0.4mL by centrifugation. These two concentrated cultures were mixed with 0.5–0.8mL of Pleodorina mating medium (Nozaki et al. 1989) in a watch glass (60mm in diameter) within Petri dishes (90mmx20mm). Mating reactions occurr 1 or 2 days after mixing male and female colonies in mating medium. Each reproductive cell in a male colony divides successively to form a bundle of male gametes (sperm packet). Sexually mature female colonies are essentially the same as that of the egetative colony. Sperm packets are released from the male colony, swim to the female colony and dissociat into the individual male gametes for syngamy. After 1 day, zygotes secrete a smooth cell wall and turn reddish brown in color after about a week. Mature zygotes are spherical in shape, with a smooth cell wall, and measure 19–28 mm in diameter.
Ecology
isolated from Lake Sagami, Japan; temperature: 20-21.5C; ph: 7.7-8.2 (Nozaki et al 2006)
Availability in culture collections or research labs
MCC-NIES
Media and growth conditions in culture
Nozaki et al 2006: AF-6 medium (Kato 1982) modified by the elimination of CaCO3 and by the addition of 400mg/L MES (Kasai et al. 2004) or VTAC medium (Nozaki et al. 1989, Kasai et al. 2004), kept at 20–22C, under a photon irradiance of 150–200 umol photons/m2/s and with a 14:10 light:dark (LD) or 16:8 LD cycle provided by cool-white fluorescent lamps
Sequence Information
Links to other databases
Index Nominum Algarum
Miscellaneous
Selected References
Nozaki H, Ott FD, Coleman AW. 2006. Morphology, molecular phylogeny and taxonomy if two new species of Pleodorina (Volvoceae, Chlorophyceae). J. Phycol. 42: 1072-1080.
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Contributors
Nedelcu AM | anedelcu@unb.ca |
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