''Saurauia'' is a genus of
plants in the family
Actinidiaceae. It comprises about over 300 species distributed in the tropics and subtropics of
Asia and South and Central America.
Genetic evidence and the cell biology of the group support
monophyly of the genus.
Monophyly of the genus is also supported by micromorphological characters and by phylogenetic analysis, although the exact evolutionary relationships of ''Saurauia'' with the other two genera of the
Actinidiaceae, ''
Actinidia
''Actinidia'' is a genus of woody and, with a few exceptions, dioecious plants native to temperate eastern Asia, occurring throughout most of China, Taiwan, Korea, and Japan, and extending north to southern areas of Russian Far East and south i ...
'' and ''
Clematoclethra
''Clematoclethra'' is a genus of plants in the family Actinidiaceae. It contains about 20 species and is endemic to subtropical and temperate regions of central and western China. Monophyly of the group is supported by genetic evidence and als ...
'', are not well understood. It is also the only extant genus within its family whose natural distribution includes areas outside of Asia (tropical South and Central America).
Description
The floral characteristics of ''Saurauia'' are similar to those in the other members of the Actinidiaceae. The main floral differences between ''Saurauia'' and the other members are that the species of ''Saurauia'' have 3-5 carpels while ''
Actinidia
''Actinidia'' is a genus of woody and, with a few exceptions, dioecious plants native to temperate eastern Asia, occurring throughout most of China, Taiwan, Korea, and Japan, and extending north to southern areas of Russian Far East and south i ...
'' has 3-30 or more and ''
Clematoclethra
''Clematoclethra'' is a genus of plants in the family Actinidiaceae. It contains about 20 species and is endemic to subtropical and temperate regions of central and western China. Monophyly of the group is supported by genetic evidence and als ...
'' has 4 or 5. Also, ''Saurauia'' is the only genus in the Actinidiaceae whose members may be
monoecious
Monoecy (; adj. monoecious ) is a sexual system in seed plants where separate male and female cones or flowers are present on the same plant. It is a monomorphic sexual system alongside gynomonoecy, andromonoecy and trimonoecy.
Monoecy is conne ...
or functionally
dioecious
Dioecy (; ; adj. dioecious , ) is a characteristic of a species, meaning that it has distinct individual organisms (unisexual) that produce male or female gametes, either directly (in animals) or indirectly (in seed plants). Dioecious reproductio ...
.
Fossil record
The oldest
fossil records of ''Saurauia'' include characteristic seed
synapomorphies
In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have ...
of the genus that are from the late
Turonian (about 89 Ma) of
Central Europe. Two
extinct
Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...
species were established, †''Saurauia alenae'' and †''Saurauia antique'', both are recorded from several assemblages in
Central Europe and ranging in age from the late
Turonian to the
Maastrichtian.
Species
Species include:
References
{{Taxonbar, from=Q137524
Ericales genera
Taxonomy articles created by Polbot