''Credneria'' is an extinct
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...
in the family or
Platanaceae
Platanaceae, the "plane-tree family", is a family of flowering plants in the order Proteales. The family consists of only a single extant genus ''Platanus'', with eight known species. The plants are tall trees, native to temperate and subtrop ...
of broad-leaf trees similar to extinct ''
Platanus
''Platanus'' is a genus consisting of a small number of tree species native to the Northern Hemisphere. They are the sole living members of the family Platanaceae.
All mature members of ''Platanus'' are tall, reaching in height. All except f ...
'' species that appeared during the
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of ...
. The genus was first described by
Zenker (
1833
Events January–March
* January 3 – Reassertion of British sovereignty over the Falkland Islands in the South Atlantic.
* February 6 – His Royal Highness Prince Otto Friedrich Ludwig of Bavaria assumes the title His Majesty Othon t ...
) and has formerly been placed in the family
Salicaceae
The Salicaceae is the willow family of flowering plants. The traditional family (Salicaceae ''sensu stricto'') included the willows, poplar, aspen, and cottonwoods. Genetic studies summarized by the Angiosperm Phylogeny Group (APG) have greatly ...
rather than Platanaceae on occasion. ''Credneria'' leaves are preserved in sandstone and less often in siltstone. The leaves are typically
obovate
The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular ...
with a pinnate-actinodromous
venation
Venation may refer to:
* Venation (botany), the arrangement of veins in leaves
* Wing venation, the arrangement of veins in insect wings
See also
*
* Vernation
Vernation (from ''vernal'' meaning ''spring'', since that is when leaves spring fort ...
and distinct suprabasal veins.
Species
Known species are:
[
*
*''Credneria biloba''
*''Credneria bohemica''
*''Credneria comparabilis''
*''Credneria cuneifolia''
*''Credneria daturaefolia'' (]Ward
Ward may refer to:
Division or unit
* Hospital ward, a hospital division, floor, or room set aside for a particular class or group of patients, for example the psychiatric ward
* Prison ward, a division of a penal institution such as a priso ...
)
*''Credneria denticulata''
*?''Credneria grewiopsoides''
*''Credneria integerrima''
*?''Credneria longifolia''
*''Credneria pachyphylla''
*''Credneria parva''
*''Credneria prophylloides'' ( Knowlton)
*''Credneria pulchra''
*?''Credneria spatiosa''
*''Credneria subserrata'' (Hampe)
*''Credneria subtriloba''
*''Credneria sudanense''
*''Credneria triacuminata'' ( Hampe)
The species ''Crednetia basinervosa'' ( Hollick), ''C. elegans'' (Hollick),Yukon River
The Yukon River ( Gwich'in: ''Ųųg Han'' or ''Yuk Han'', Yup'ik: ''Kuigpak'', Inupiaq: ''Kuukpak'', Deg Xinag: ''Yeqin'', Hän: ''Tth'echù'' or ''Chuu k'onn'', Southern Tutchone: Chu Nìikwän, russian: Юкон, Yukon) is a major watercour ...
in Alaska are also possibly representatives of ''Pseudoprotophyllum boreale'', but the known fossil material for the species was considered to incomplete to make a determination.
References
{{Taxonbar, from=Q1139441
Cretaceous plants
Platanaceae
Salicaceae
Fossil record of plants