The origin and early diversification of the Ulvophyceae likely took place in the late Neoproterozoic.[5][6] Although most contemporary ulvophytes are marine macroalgae (seaweeds), ancestral ulvophytes may have been freshwater, unicellular green algae. Molecular phylogenetic evidence suggests that macroscopic growth was achieved independently in the various major lineages of Ulvophyceae (Ulvales-Ulotrichales, Trentepohliales, Cladophorales, Bryopsidales and Dasycladales).[6]
Current hypothesis on relationships among the main clades of Ulvophyceae[7][8] are shown below.
^Stewart KD, Mattox KR (1978). "Structural evolution in the flagellated cells of green algae and land plants". BioSystems10 (1–2): 145–152. doi:10.1016/0303-2647(78)90036-9. PMID656563.
^Adl SM, Simpson AGB, Farmer MA, Andersen RA, Anderson OR, Barta JR, Bowser SS, Brugerolle G, Fensome RA, Fredericq S, James TY, Karpov S, Kugrens P, Krug J, Lane CE, Lewis LA, Lodge J, Lynn DH, Mann DG, McCourt RM, Mendoza L, Moestrup Ø, Mozley-Standridge SE, Nerad TA, Shearer CA, Smirnov AV, Speigel FW, Taylor MFJR (2005). "The new higher level classification of eukaryotes with emphasis on the taxonomy of protists". Journal of Eukaryotic Microbiology52 (5): 399–451. doi:10.1111/j.1550-7408.2005.00053.x. PMID16248873.
^ abGuiry, M.D. & Guiry, G.M. (2007). "Class: Ulvophyceae taxonomy browser". AlgaeBase version 4.2 World-wide electronic publication, National University of Ireland, Galway. Retrieved 2007-09-23.
^Graham LE, Graham JM, Wilcox LW (2009) Algae. 2nd Edition. Benjamin Cummings (Pearson), San Francisco, CA
^Verbruggen, H.; Ashworth, M.; LoDuca, S.T.; Vlaeminck, C.; Cocquyt, E.; Sauvage, T.; Zechman, F.W.; Littler, D.S.; Littler, M.M.; Leliaert, F. (2009). "A multi-locus time-calibrated phylogeny of the siphonous green algae". Mol. Phylogenet. Evol.50: 642–653. doi:10.1016/j.ympev.2008.12.018.
^ abCocquyt, E.; Verbruggen, H.; Leliaert, F.; De Clerck, O. (2010). "Evolution and Cytological Diversification of the Green Seaweeds (Ulvophyceae)". Mol. Biol. Evol.27 (9): 2052–2061. doi:10.1093/molbev/msq091. ISSN0737-4038.
^Škaloud, Pavel; Kalina, Tomáš; Nemjová, Katarína; De Clerck, Olivier; Leliaert, Frederik (2013). "Morphology and Phylogenetic Position of the Freshwater Green MicroalgaeChlorochytrium(Chlorophyceae) andScotinosphaera(Scotinosphaerales, ord. nov., Ulvophyceae)". Journal of Phycology49 (1): 115–129. doi:10.1111/jpy.12021. ISSN0022-3646.