Streptophyta (/strɛpˈtɒfɪtə,ˈstrɛptoʊfaɪtə/ ), informally the streptophytes (/ˈstrɛptəfaɪts/, from the Greek strepto 'twisted', for the morphology of the sperm of some members), is a clade of plants. The composition of the clade varies considerably between authors, but the definition employed here includes land plants and all green algae except the Chlorophyta and possibly the more basal Mesostigmatophyceae, Chlorokybophyceae, and Spirotaenia.[3]
The composition of Streptophyta and similar groups (Streptophytina, Charophyta) varies in each classification.[4][citation needed] Some authors are more restrictive, including only the Charales and Embryophyta (e.g., Streptophyta Jeffrey 1967; Adl et al. 2012, Streptophytina Lewis & McCourt 2004), others include more groups (e.g., Charophyta Lewis & McCourt 2004; Karol et al. 2009; Adl et al. 2012, Streptophyta Bremer, 1985; de Reviers 2002; Leliaert et al. 2012, Streptobionta Kenrick & Crane 1997; some authors use this broader definition, but exclude the Embryophyta, e.g., Charophyta Cavalier-Smith 1993;[5] Leliaert et al. 2012, Charophyceae Mattox & Stewart, 1984, Streptophycophytes de Reviers, 2002).
The organism, streptophyta, includes both unicellular and multicellular organisms. All living green plants belong to the major phylums including Streptophyta and chlorophyta. The Streptophyta phylum contains the charophyte green algae in freshwater habitat and also all land plants. Another thing about streptophyta is that this organism reproduces sexually by conjugation. There is another organism that is very similar to streptophyta is the Mesostigma viride organism and it is a green flagellate. Streptophyta include the charophycean lineage along with bryophytes and tracheophytes. Bryophytes are land plants that include liverworts, hornworts and mosses, and tracheophytes are vascular plants. The organism, streptophyta, was also found in Bahia, Brazil, and is characterized by having cell walls composed of a single unit,without pores or other ornamentations. The phylum Streptophyta comprises all land plants and six monophyletic groups of charophycean green algae.[6]
These earlier classifications have not taken into account that the Coleochaetophyceae and the Zygnemophyceae appear to have emerged in the Charophyceae + Embryophyta clade, resulting in the synonymy of the Phragmoplastophyta and Streptophytina/Streptophyta sensu stricto (a.k.a. Adl 2012) nomenclature.[7]
Below is a reconstruction of Streptophyta relationships, based on molecular and morphological data.[9][10][11]