Krithodeophyton

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Krithodeophyton
Temporal range: Early Devonian
Scientific classification Red Pencil Icon.png
Kingdom: Plantae
Clade: Tracheophytes
Clade: Barinophytes
Genus: Krithodeophyton
D.Edwards
Species:
K. croftii
Binomial name
Krithodeophyton croftii
D.Edwards (1968)

Krithodeophyton is a genus of lower Devonian plant with branching axes. It is considered to be a barinophyte. [1] [2]

Phylogeny

The phylogenetic position of the barinophytes remains disputed. Kenrick and Crane in 1997 called the group the Barinophytaceae and placed it in their Sawdoniales, well nested within the zosterophylls. [3] Taylor et al. in 2009 considered the barinophytes to be possible lycopsids rather than zosterophylls. [4] Hao and Xue in 2013 suggested that they were not lycopsids, instead falling between this group and the euphyllophytes. [5]

Related Research Articles

<span class="mw-page-title-main">Lycophyte</span> Broadly circumscribed group of spore bearing plants

The lycophytes, when broadly circumscribed, are a vascular plant (tracheophyte) subgroup of the kingdom Plantae. They are sometimes placed in a division Lycopodiophyta or Lycophyta or in a subdivision Lycopodiophytina. They are one of the oldest lineages of extant (living) vascular plants; the group contains extinct plants that have been dated from the Silurian. Lycophytes were some of the dominating plant species of the Carboniferous period, and included the tree-like arboresencent lycophytes, some of which grew over 40 metres (130 ft) in height, although extant lycophytes are relatively small plants.

<span class="mw-page-title-main">Zosterophyll</span> Group of extinct land plants that first appeared in the Silurian period

The zosterophylls are a group of extinct land plants that first appeared in the Silurian period. The taxon was first established by Banks in 1968 as the subdivision Zosterophyllophytina; they have since also been treated as the division Zosterophyllophyta or Zosterophyta and the class or plesion Zosterophyllopsida or Zosteropsida. They were among the first vascular plants in the fossil record, and had a world-wide distribution. They were probably stem-group lycophytes, forming a sister group to the ancestors of the living lycophytes. By the late Silurian a diverse assemblage of species existed, examples of which have been found fossilised in what is now Bathurst Island in Arctic Canada.

<i>Tortilicaulis</i> Extinct genus of Devonian plants

Tortilicaulis is a moss-like plant known from fossils recovered from southern Britain, spanning the Silurian-Devonian boundary. Originally recovered from the Downtonian of the Welsh borderlands, Tortilicaulis has since been recovered in the famous Ludlow Lane locality.

<i>Leclercqia</i> (plant) Extinct genus of spore-bearing plants

Leclercqia is a genus of early ligulate lycopsids (clubmosses), known as fossils from the Middle Devonian of Australia, North America, Germany, and Belgium. It has been placed in the Protolepidodendrales.

<i>Zosterophyllum</i> Extinct genus of spore-bearing plants

Zosterophyllum was a genus of Silurian-Devonian vascular land plants with naked branching axes on which usually kidney-shaped sporangia were arranged in lateral positions. It is the type genus for the group known as zosterophylls, thought to be part of the lineage from which modern lycophytes evolved. More than 20 species have been described.

Crenaticaulis was an early genus of slender, dichotomously branching, leafless land plants, known from the Devonian period and first described in 1969. They were probably allied to the zosterophylls, and are assigned to subdivision Zosterophyllophytina, or class Zosterophyllopsida. They bore branches and scalariform tracheids.

<i>Yunia</i> Extinct genus of spore-bearing plants

Yunia is a genus of extinct vascular plants from the Early Devonian. It was first described from the Posongchong Formation of Yunnan, China. The leafless plant consisted of spiny stems, some 2 to 5 cm wide, which branched dichotomously at wide angles in a cruciate arrangement. Each stem contained vascular tissue with one or two strands of protoxylem. The spore-forming organs (sporangia) were elongated and borne on short stalks. The spores had a relatively smooth sculptural pattern and were trilete.

Huia is a genus of extinct vascular plants of the Early Devonian. The genus was first described in 1985 based on fossil specimens from the Posongchong Formation, Wenshan district, Yunnan, China.

<i>Adoketophyton</i> Extinct genus of spore-bearing plants

Adoketophyton is a genus of extinct vascular plants of the Early Devonian. The plant was first described in 1977 based on fossil specimens from the Posongchong Formation, Wenshan district, Yunnan, China. These were originally named Zosterophyllum subverticillatum; later the species was transferred to a new genus as Adoketophyton subverticillatum. One cladistic analysis suggested that it is a lycophyte, related to the zosterophylls. Other researchers regard its placement within the vascular plants as uncertain.

Discalis is a genus of extinct vascular plants of the Early Devonian. The name is derived from the Greek δίσκος, referring to the disc-shaped sporangia. The genus was first described by Hao in 1989 based on fossil specimens from the Posongchong Formation, Wenshan district, Yunnan, China.

Distichophytum is a genus of extinct vascular plants of the Late Silurian (Ludfordian) to Early Devonian (Emsian), around 426 to 393 million years ago. The genus has a tangled taxonomic history, also being known as Bucheria and Rebuchia.

Gosslingia was a genus of Early Devonian land plant with branching axes. Fossils have been from the Lochkovian to the Pragian, 419 to 408 million years ago.

Oricilla was a genus of Early Devonian land plant with branching axes. Fossils have been found from the Pragian to the Emsian.

<i>Nothia aphylla</i> Extinct species of spore-bearing plant

Nothia was a genus of Early Devonian vascular plants whose fossils were found in the Rhynie chert in Scotland. It had branching horizontal underground stems (rhizomes) and leafless aerial stems (axes) bearing lateral and terminal spore-forming organs (sporangia). Its aerial stems were covered with small 'bumps' (emergences), each bearing a stoma. It is one of the best described early land plants. Its classification remains uncertain, although it has been treated as a zosterophyll. There is one species, Nothia aphylla.

<i>Barinophyton</i> Extinct genus of plants

Barinophyton was a genus of early land plant with branching axes. It is placed in a group of early vascular plants (tracheophytes), the barinophytes, a group that has been given various ranks and scientific names. Known fossils are of Devonian to Carboniferous age.

Protobarinophyton was a genus of Silu-Devonian land plant with branching axes. It is placed in a group of early vascular plants (tracheophytes), the barinophytes, a group that has been given various ranks and scientific names.

Wenshania is a genus of extinct vascular plants found in the Posongchong Formation, Yunnan, China, which is of Early Devonian age. Plants consisted of leafless stems with simple dichotomous branching, and bore spore-forming organs or sporangia all around the sides of stems. Wenshania is part of the broadly defined group of zosterophylls.

Demersatheca is a genus of extinct vascular plants of the Early Devonian. Fossils were first found in the Posongchong Formation of eastern Yunnan, China. The plant had smooth leafless stems at least 1 mm in diameter, but only regions which bore spore-forming organs or sporangia are well-known. Sporangia were borne in 'spikes' or strobili, at least 40 mm long; one had 32 sporangia. Sporangia were arranged in four rows, two sporangia being opposite to one another on the stem with the next two being at right angles. Each sporangium consisted of two 'valves' which opened at the top to release their spores. A particular feature of Demersatheca which distinguishes it from other zosterophylls is that the stalk-less sporangia were sunken into the stem of the spike, so that the outer valve was flush with the surface.

Gosslingiales is an order of extinct zosterophylls. The zosterophylls were among the first vascular plants in the fossil record, and share an ancestor with the living lycophytes. The group has been divided up in various ways. Hao and Xue in 2013 used the presence or absence of terminal sporangia as a major dividing feature. The order Zosterophyllales was used for species with terminal as well as lateral sporangia, which were considered to have determinate growth, with their sporangia generally being arranged in spikes. The paraphyletic order Gosslingiales was used for species without terminal sporangia, which were considered to have indeterminate growth, with fertile branches generally circinate. Species assignable to the Gosslingiales made up about 9% of all confirmed species in the Early Devonian flora.

The barinophytes are a group of extinct vascular plants (tracheophytes). Their relationship with other vascular plants is unclear. They have been treated as the separate class Barinophytopsida, the order Barinophytales of uncertain class and as a family or clade Barinophytaceae within the zosterophylls. They have also been considered to be possible lycopodiopsids.

References

  1. Brauer, D. F. (1981). "Heterosporous, barinophytacean plants from the Upper Devonian of North America and a discussion of the possible affinities of the Barinophytaceae". Review of Palaeobotany and Palynology. 33 (2–4): 347–362. doi:10.1016/0034-6667(81)90092-0.
  2. Cichan, M.; Taylor, T.; Brauer, D. (1984). "Ultrastructural studies of in situ Devonian spores: Protobarinophyton pennsylvanicum Brauer". Review of Palaeobotany and Palynology. 41 (3–4): 167. doi:10.1016/0034-6667(84)90044-7.
  3. Kenrick, Paul & Crane, Peter R. (1997). The Origin and Early Diversification of Land Plants: A Cladistic Study. Washington, D.C.: Smithsonian Institution Press. p. 172. ISBN   978-1-56098-730-7.
  4. Taylor, T.N.; Taylor, E.L. & Krings, M. (2009). Paleobotany, The Biology and Evolution of Fossil Plants (2nd ed.). Amsterdam; Boston: Academic Press. pp. 325–326. ISBN   978-0-12-373972-8.
  5. Hao, Shougang & Xue, Jinzhuang (2013). The early Devonian Posongchong flora of Yunnan: a contribution to an understanding of the evolution and early diversification of vascular plants. Beijing: Science Press. pp. 55, 246. ISBN   978-7-03-036616-0 . Retrieved 2019-10-28.