Home / Chlorophyceae / Filamentous / Unbranched / Schizomeris
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Name derivation:
Classification:
Sphaeroplea C. Agardh 1824; 6 of 22 species descriptions are currently accepted taxonomically (Guiry and Guiry 2014). Order Chlamydomonadales; Family Sphaeropleaceae
Morphology:
Green to red uniseriate filaments with coenocytic cells (often paired nuclei) and annular (ring-shaped) chloroplasts separated by clear cytoplasm. Cells are cylindrical, much longer than wide. Generally 10 – 50 µm diameter, but at least one species reported to be up to 170 µm diameter (Guiry and Guiry 2013). Crosswalls between adjacent cells vary from thin to much chicker in some species. Asexual division by fragmentation of filaments. Sexual reproduction is oogamous or occasionally anisogamous. Oogonia produce several spherical green oogonia in one or more rows. Antheridia usually are on the same filament (monoecious). All gametes are biflagellate (female as well as male). Zygotes eventually turn orange-red before discharge, and are capable of prolonged dehydration. More extensive description of life cycle by Guiry and Guiry can be found online.
Similar genera:
Habitat:
Freshwater, free-floating in temporary pools (e.g. roadside ditches) subject to prolonged dry periods. Ephemeral and episodic, reported missing in some cases for years (Guiry and Guiry 2013).
References:
Guiry, M.D. and G.M. Guiry 2013. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 24 July 2013.