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Goldstein M. 1964. Speciation and mating behavior in ''Eudorina''. J. Protozool. 11(3): 317-344

cells are arranged in distinct tiers within a confluent double-layered gelatinous envelope

when daughter colony formation occurs, the small anterior cells may remain vegetative or may divide; if division occurs, it is delayed and the resulting colonies posses 4, 8 or 16 cells (Goldstein 1964)

-cells are arranged in distinct tiers within a confluent double-layered gelatinous envelope

-when daughter colony formation occurs, the small anterior cells may remain vegetative or may divide; if division occurs, it is delayed and the resulting colonies posses 4, 8 or 16 cells (Goldstein 1964)

-cells are arranged in distinct tiers within a confluent double-layered gelatinous envelope

- when daughter colony formation occurs, the small anterior cells may remain vegetative or may divide; if division occurs, it is delayed and the resulting colonies posses 4, 8 or 16 cells (Goldstein 1964)

cells are arranged in distinct tiers within a confluent double-layered gelatinous envelope

when daughter colony formation occurs, the small anterior cells may remain vegetative or may divide; if division occurs, it is delayed and the resulting colonies posses 4, 8 or 16 cells (Goldstein 1964)

-colonies composed of 16 or 32 cells, with the anterior tier of cells markedly reduced in size in 32-celled colonies

-cells are arranged in distinct tiers within a confluent double-layered gelatinous envelope

- when daughter colony formation occurs, the small anterior cells may remain vegetative or may divide; if division occurs, it is delayed and the resulting colonies posses 4, 8 or 16 cells (Goldstein 1964)

- heterogamous and dioecious

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 brow

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 brow

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

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 20–221 C, under a photon irradiance of 150–200 mmol

photons/m2/s and with a 14:10 light:dark (LD) or 16:8

LD cycle provided by cool-white fluorescent lamps

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 20–221 C, under a photon irradiance of 150–200 mmol photons/m2/s and with a 14:10 light:dark (LD) or 16:8 LD cycle provided by cool-white fluorescent lamps

heterothallic; anysogamous

heterothallic; anisogamous

isolated fron Lake Sagami, Japan; temperature: 20-21.5C; ph: 7.7-8.2 (Nozaki et al 2006)

Nozaki et al 2006: AF-6 medium (Kato 1982) modified by the elimination of

CaCO3 and by the add

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!!!Images

!!!Taxonomic characters

clearly distinguished from other Eudorina/Pleodorina species by having obligative somatic cells that are distributed only in the anterior portion of 16- or 32-celled colonies, and by containing a single large pyrenoid in the chloroplast of mature reproductive cells (Nozaki et al 2006)

!!!Morphology / Structure

colonies ovoid or spherical in shape; 16 or 32 cells embedded at the periphery of the gelatinous matrix (often wavy); 4 or 12 obligative somatic cells (at the anterior pole) in 16- or 32-celled colonies, respectively;

!!!Life history

anisogamous sexual reproduction

!!!Ecology

isolated from a small muddy stream near College Park, south of College

** [Pleodorina thompsonii]

clearly distinguished from ''P. californica'', ''P. japonica ''and ''P. indica ''by its individual cellular sheaths that 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)