Home / Greens / Filamentous / Unbranched / Oedogonium
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Name derivation:
Oidos = swelling, tumor; Gonos = offspring, seed.
Classification:
Oedogonium Link ex. Hirn 1900; 498 of 1382 species descriptions are currently accepted taxonomically (Guiry and Guiry 20140. Order Oedogoniales; Family Oedogoniaceae
Morphology:
Unbranched filament that is often attached. Cells are cylindrical, some with extensive ringlike “caps” (growth scars because of unusual wall formation) below the cross wall. Each cell has a parietal chloroplast, and pyrenoids. More description online (Guiry and Guiry 2014). At least some species of Odeogonium produce dwarf male filaments that attach to much larger female sporophytic filaments. Photomicrographs of the development of these dwarfs is clearly documented in D’Amico, Leonardi and Caceres (2013).
Similar genera:
Polyspermy and plasmogamy:
Polyspermy, presumably because of plasmogamy (fusion of cell contents without fusion of nuclei, common in fungi), has been observed in Oedogonium during fertilization of an ovum with two spermatozoids (Hoffman 1973). A temporary N+N, common in the fusion of fungal hyphae (or N+xN where x = number of male gametes) would occur, until fusion of nuclei occurs. Presumably a mechanism is present to prevent trisomy.
Vampire amoeba predator:
Vampyrella pendula, a ‘vampire amoeba’, selectively feeds on Oedogonium spp. with a penetrating pseudopod (Hess, Sausen and Mdlkonian 2012).
Habitat:
Found in a habitat similar to Bulbochaete, which is in freshwater habitats such as ponds, lakes, streams, or marshes. It is sometimes epiphytic on submerged plants.
References:
D’Amico, S.L., P.I. Leonardi and E.J. Cáceres 2013. Ultrastructure of multicellular dwarf males with external gametangium in Oedogonium macrandrium (Oedogoniales, Chlorophyta). Biocell 37(3):85-91. online Guiry, M.D. and G.M. Guiry 2014. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 2 May 2014. Hirn, K.E. 1900. Monographie und iconographie der Oedogoniaceen. Acta Societatis Scientiarum Fennicae 27: i-iv, 1-394, XXVII figs, XLIV plates. Hoffman, L. 1973. Fertilization in Oedogonium. II. Polyspermy. Journal of Phycology 9:296-301. online John, D.M., B.A. Whitton, and A.J. Brook 2011. The Freshwater Algal Flora of the British Isles. Cambridge University Press. Wehr, J.D. and R. Sheath 2003. Freshwater Algae of North America: Ecology and Classification. Academic Press.