''Ramoferis'' is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of extinct

vascular plant Vascular plants (), also called tracheophytes (, ) or collectively tracheophyta (; ), are plants that have lignin, lignified tissues (the xylem) for conducting water and minerals throughout the plant. They also have a specialized non-lignified Ti ...

s of the

Pragian The Pragian is one of three faunal stages in the Early Devonian Epoch. It lasted from 410.8 ± 2.8 million years ago to 407.6 ± 2.8 million years ago. It was preceded by the Lochkovian Stage and followed by the Emsian Stage. The most important ...

stage of the

Early Devonian The Early Devonian is the first of three Epoch (geology), epochs comprising the Devonian period, corresponding to the Lower Devonian Series (stratigraphy), series. It lasted from and began with the Lochkovian Stage , which was followed by the Pr ...

, around . It is considered to be a

zosterophyll 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 Zostero ...

, one of a group of plants that were related to the ancestors of the modern lycopsids. Fossils were found in the Posongchong Formation in

Guangnan County Guangnan County (; Zhuang languages, Zhuang: ) is located in Wenshan Zhuang and Miao Autonomous Prefecture, Yunnan province, China. The seat of Guangnan, known today as Liancheng (), was the heart of the Gouding Kingdom () that lasted approximat ...

Yunnan Yunnan; is an inland Provinces of China, province in Southwestern China. The province spans approximately and has a population of 47.2 million (as of 2020). The capital of the province is Kunming. The province borders the Chinese provinces ...

, in southwestern China, where they occur as compressions.

Description

The first species to be described was ''Ramoferis amalia''. The plant branched isotomously (equally) many times, with branches forming angles of about 30–60°. Usually the axes (stems) were 3–4 mm across, although some were up to 5 mm across. The longest axis found bearing sporangia was about 12 cm long, branching four or five times, with the branching intervals decreasing towards the top. The smallest terminal branchlets were less than 1 mm wide and about 6-10 mm long.

Sporangia A sporangium (from Late Latin, ; : sporangia) is an enclosure in which spores are formed. It can be composed of a unicellular organism, single cell or can be multicellular organism, multicellular. Virtually all plants, fungus, fungi, and many ot ...

were borne on short stalks both terminally and laterally. Some were found below the first branching point of the main axis, others were gathered into a spike. The sporangia were flattened, usually about 3–6 mm wide and 2.5–5 mm high. Viewed from the front, the sporangia were ovoid or pear-shaped, narrowing towards the stalk. They opened (dehisced) along a narrow rim at the edge opposite the stalk (the distal edge), producing two equal valves. Only poorly preserved spores were found, 48–77 μm in diameter. Nothing is known about the internal anatomy of the axes. A second species, known only as ''Ramoferis'' cf. ''amalia'', was described from fossils found in a slightly different location. Only limited material was found. Differences regarded as significant included the branching angle being greater, 60–70°; the more kidney (reniform) shaped sporangia; the longer sporangial stalks; and the less distinct spikes of sporangia.

Taxonomy

Hao and Xue place ''Ramoferis'' in class Zosterophyllopsida, order Zosterophyllales. They use Zosterophyllales for species with both terminal and lateral sporangia;

Gosslingiales Gosslingiales is an Order (biology), order of extinct zosterophylls. The zosterophylls were among the first vascular plants in the fossil record, and share an ancestor with the Lycopodiopsida, living lycophytes. The group has been divided up in ...

have only lateral sporangia.

Phylogeny

cladistic Cladistics ( ; from Ancient Greek 'branch') is an approach to biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is ...

analysis by Hao and Xue in 2013 placed ''Ramoferis'' clearly within their Zosterophyllales clade:

References

Bibliography

* {{Taxonbar, from=Q85795816 Early Devonian plants Pragian life Zosterophylls Prehistoric lycophyte genera