''Gumuia'' is a

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of extinct

vascular plant Vascular plants (), also called tracheophytes () or collectively Tracheophyta (), form a large group of land plants ( accepted known species) that have lignified tissues (the xylem) for conducting water and minerals throughout the plant. They al ...

s 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 P ...

(Pragian or Siegenian, around ). The genus was first described in 1989 based on fossil specimens from the Posongchong Formation,

Wenshan district Wenshan District is a District (Taiwan), district in Taipei, Taiwan. It is the southernmost district of the twelve districts in Taipei. ''Wenshan'' previously referred to the region south of the Taipei Basin (including Sindian City, Xindian and ...

, Yunnan, China.

Description and phylogeny

The

sporophyte A sporophyte () is the diploid multicellular stage in the life cycle of a plant or alga which produces asexual spores. This stage alternates with a multicellular haploid gametophyte phase. Life cycle The sporophyte develops from the zygote pr ...

of ''G. zyzzata'' consisted of leafless stems (axes) with an apparently sympodial organization. Fertile stems had a spike-like organization, with both lateral and terminal

sporangia A sporangium (; from Late Latin, ) is an enclosure in which spores are formed. It can be composed of a single cell or can be multicellular. Virtually all plants, fungi, and many other lineages form sporangia at some point in their life cy ...

(spore-forming organs); successive sporangia developed on alternate sides of short stems. The genus was tentatively placed in the "

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 Zosteroph ...

s". (the English title in the online version has the misspelling "Gumoia") A cladogram published in 2004 by Crane et al. places ''Gumia'' in a

paraphyletic In taxonomy (general), taxonomy, a group is paraphyletic if it consists of the group's most recent common ancestor, last common ancestor and most of its descendants, excluding a few Monophyly, monophyletic subgroups. The group is said to be pa ...

stem group In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor. ...

of broadly defined "zosterophylls", basal to the lycopsids (living and extinct clubmosses and relatives). Hao and Xue in 2013 listed the genus as a zosterophyll.

References

External links

Cladogram
from {{Taxonbar, from=Q5618261 Early Devonian plants Zosterophylls Prehistoric lycophyte genera