In terms of phytocoenotic confinement, tracheophyte
plants are dominated by meadow (48.4%) and forest (40.2%) species.
(1973), Al-Houty and Syrett (1984), and Syrett and Al-Houty (1984) determined that charophytes and embryophytes (bryophytes and tracheophytes
) utilize the enzyme glycolate oxidase in their photorespiratory pathway; chlorophytes (meaning green algae other than charophytes) utilize glycolate dehydrogenase instead.
Because hornworts have wall xylans, stomates, and a well-differentiated sporophyte meristem similar to those of tracheophytes
, there is reason to suspect they are closer to the tracheophytes
hornworts share a common ancestor with tracheophytes
, mosses form a sister group to this combined lineage, and liverworts mark the transition to land, ..." (Chp.
The Hornworts (Anthocerophytina) are a small (about 500 species in 12 genera) but evolutionarily important group as the most current phylogenies find them to be the closest extant relatives of the tracheophytes
(Carafa et al., 2005; Renzaglia et al., 2009; Villarreal et al., 2010).
: Plants with a well-defined vascular system.
Moreover, most molecular studies suggest that tracheophytes
are derived from within a paraphyletic grouping of 'bryophytes' (Qiu et al., 1998; Karol et al., 2001).