| Barinophyte | |
|---|---|
Scientific classification | |
| Kingdom: | Plantae |
| Clade: | Tracheophytes |
| Clade: | †Barinophytes |
| Genera | |
Thebarinophytes are a group of extinctvascular plants (tracheophytes). Their relationship with other vascular plants is unclear. They have been treated as the separate classBarinophytopsida, the orderBarinophytales of uncertain class and as a family or cladeBarinophytaceae within thezosterophylls. They have also been considered to be possiblelycopodiopsids.[1]
Barinophyton is the type genus of the group;Protobarinophyton is similar. They werevascular plants with anexarchprotostele. Plants consisted of alternatively arranged branches, apparently without leaves or enations, with theirsporangia arranged in two rows on one-sided spike-like structures that developed on side shoots. Each sporangium was born on a curved bract-like appendage (a "sporangiferous appendage") and contained several thousand microspores, about 30–40 μm in diameter and about 30 megaspores, 410–560 μm in diameter, so that the plants were heterosporous. A similar pattern of spore sizes and numbers has been found in theprogymnospermArchaeopteris.[2]
Dibracophyton has been tentatively assigned to this group. It does have some outgrowths on the lower parts of the stems (axes), which raises the possibility that more fossil material might show that other barinophytes did not have naked stems.[1]
Two very different cladograms have been produced showing the evolutionary relationships of taxa assigned to the barinophytes. Kenrick and Crane in 1997 placed two species ofBarinophyton and the genusProtobarinophyton in the Barinophytaceae in theirSawdoniales, well nested within thezosterophylls.[3] A summary cladogram produced by Crane et al. in 2004, showsBarinophyton andProtobarinophyton as 'core' zosterophylls.[4]
| lycophytes |
| |||||||||||||||||||||
Taylor et al. in 2009 did not present a cladogram, but considered the barinophytes to be possible lycopsids rather than zosterophylls.[2] By contrast, Hao and Xue in 2013 do not even placeDibracophyton, which they consider to be a possible barinophyte, within the lycopodiopsids, instead putting it between this group and theeuphyllophytes.[5]
| |||||||||||||||||||
Genera that are placed, or tentatively placed, in the barinophytes (with the group treated at different ranks) include:[1][6][3][7][8]
 | Thispaleobotany-related article is astub. You can help Wikipedia byexpanding it. |