''Codon'' is a small

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 plants from

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

in the family Codonaceae in the order

Boraginales Boraginales is an order of flowering plants in the asterid clade, with a total of about 125 genera and 2,700 species. Different taxonomic treatments either include only a single family, the Boraginaceae, or divide it into up to eleven families. ...

. The genus ''Codon'' comprises two species. ''Codon'' was placed in the Hydrophyllaceae and

Boraginaceae Boraginaceae, the Borago, borage or forget-me-not family, includes about 2,000 species of shrubs, trees, and herbs in 146 to 154 genus, genera with a worldwide distribution. The APG IV system from 2016 classifies the Boraginaceae as single famil ...

. Recent phylogenetic analysis place it as

sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...

to the Wellstediaceae and

''s.str''. The species of the genus ''Codon'' are annual to perennial herbs. The whole plants are densely covered with strong mineralised, unicellular trichomes on cystolithic foot-cells. The plants are growing from strong taproots. The flowers are tetracyclic and polymerous. The whorls are 10- to 20-merous with a high variability even within one plant individual. Most common are 12-merous flowers. The

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 Etymology The term ''sepalum'' ...

s are free. The

petal Petals are modified leaves that form an inner whorl surrounding the reproductive parts of flowers. They are often brightly coloured or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corol ...

s are fused up to three quarter of their length. The bases of the filaments are fused with the base of the corolla. The fused parts of the filaments form septa. These septa form separate nectar chambers. The

gynoecium Gynoecium (; ; : gynoecia) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl (botany), whorl of a flower; it consists ...

is superior and consists of two

carpels Gynoecium (; ; : gynoecia) is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of a flower; it consists of (one or more) ...

. The base of the

forms a lobed nectary disc. Each lobe is covered with nectarostomata and secretes nectar in the nectar chambers. The flowers are bell-shaped and white in ''C. royenii'' and saucer-shaped and yellow in ''C. schenckii''. The

fruit In botany, a fruit is the seed-bearing structure in flowering plants (angiosperms) that is formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate their seeds. Edible fruits in particular have long propaga ...

is an apical-loculicidal capsule.

Seed In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...

s are reticulately sculptured.

Species

References

Boraginaceae Boraginaceae genera {{boraginaceae-stub