BIOTIC

BIOTIC Species Information for Saccorhiza polyschides

Researched by

Nicola White

Data supplied by

MarLIN

Refereed by

This information is not refereed.

Reproduction/Life History

Alternation of generations

Spores (sexual / asexual)

Reproductive Season

October to May

Reproductive Location

Insufficient information

Semelparous

Life span

<1 year

Age at reproductive maturity

<1 year

Generation time

<1 year

Fecundity

Insufficient information

Egg/propagule size

Zoospores ca 5 µm diam.

Fertilization type

External

Larvae/Juveniles
Larval/Juvenile dispersal potential	100-1000m	Larval settlement period	Insufficient information
Duration of larval stage	<1 day

Reproduction Preferences Additional Information

Saccorhiza polyschides has a typical Laminarian life history in which a macroscopic diploid sporophyte alternates with a microscopic haploid gametophyte.
The species is an annual. Sporophytes typically have a life span of less than 10 months. However, plants produced late in the season may over-winter and live for 14-16 months.
The base of the lamina, the stipe frills and the bulb are covered in unilocular sporangia, which produce zoospores by meiosis. Each sporangia contains 128 zoospores. The flagellated zoospores are about 5 microns in diameter and possess an eyespot which makes them strongly phototactic. The zoospores may be transported at least 200 m from the parent and they loose their flagella after 24 hrs and settle on the available substrata. 75% of the zoospores settle on the substrata with 24 hours.
The zoospores develop into microscopic dioecious gametophytes. Gametophytes take the form of unicellular or filamentous structures. The male gametophytes are more branched than the females and have more numerous, smaller and paler cells. These become fertile in under 10 days in optimal conditions. Male gametophytes release motile sperm that fertilize eggs of female gametophytes, the resultant zygote develops into the new sporophyte.

Reproduction References